Aerodynamics - Revision history

Designing Buildings at 09:19, 28 October 2025

2025-10-28T09:19:37Z

← Older revision		Revision as of 09:19, 28 October 2025
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	* Wind tunnels.		* Wind tunnels.

−	[[Category:DCN_Commentary]] [[Category:DCN_Definition]] [[Category:DCN_Product_Knowledge]] [[Category:DCN_Project_Knowledge]] [[Category:DCN_Research,_Development_and_Innovation]] [[Category:DCN_Software]] [[Category:Definitions]] [[Category:History~~]] [[Category:Projects_and_case_studies~~]] [[Category:Research_/_Innovation]] [[Category:Theory]] [[Category:Health_and_safety_/_CDM]] [[Category:Regulations]] [[Category:Standards_/_measurements]] [[Category:Sustainability]]	+	[[Category:DCN_Commentary]] [[Category:DCN_Definition]] [[Category:DCN_Product_Knowledge]] [[Category:DCN_Project_Knowledge]] [[Category:DCN_Research,_Development_and_Innovation]] [[Category:DCN_Software]] [[Category:Definitions]] [[Category:History]] [[Category:Research_/_Innovation]] [[Category:Theory]] [[Category:Health_and_safety_/_CDM]] [[Category:Regulations]] [[Category:Standards_/_measurements]] [[Category:Sustainability]]

Designing Buildings at 12:52, 4 October 2022

2022-10-04T12:52:00Z

Editor at 10:49, 21 September 2022

2022-09-21T10:49:18Z

← Older revision		Revision as of 10:49, 21 September 2022
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	In physics and engineering, both aerodynamics and fluid dynamics as well as hydrodynamics are considered subdisciplines of fluid mechanics that describes the flow of fluids—liquids and gases. The first scientific paper that used a 3D model in fluid flow problems was published by John Hess and A.M.O. Smith in 1967 and marked the birth of what is known as Computational Fluid Dynamics (CFD) which is the digital form of aerodynamic analysis. It allowed aerodynamicists to gain a more detailed understandings of flow fields around or through objects and in particular helped in the modelling of larger objects that could not be modelled directly iin wind tunnels, such as buildings.		In physics and engineering, both aerodynamics and fluid dynamics as well as hydrodynamics are considered subdisciplines of fluid mechanics that describes the flow of fluids—liquids and gases. The first scientific paper that used a 3D model in fluid flow problems was published by John Hess and A.M.O. Smith in 1967 and marked the birth of what is known as Computational Fluid Dynamics (CFD) which is the digital form of aerodynamic analysis. It allowed aerodynamicists to gain a more detailed understandings of flow fields around or through objects and in particular helped in the modelling of larger objects that could not be modelled directly iin wind tunnels, such as buildings.
		+
		+	For example here is a CFD analysis of a Kármán vortex, which was theorised in the 1900's, impacted the towers at Ferrybridge in 1965 and [https://youtu.be/IDeGDFZSYo8 modelled in the twentieth century by Cyclone Fluid Dynamics.]

	= Aerodynamics in buildings today =		= Aerodynamics in buildings today =

−	~~<ul>~~	+	Today fluid mechanics, aerodynamics, fluid dynamics as well as on occasions hydrodynamics and in particular benefitting from CFD analysis techniques has a significant role to play in the design of buildings and is used in a number of specific areas:
−	~~<li><p>Tall~~ buildings and skyscrapers.~~</p>~~	+
−	~~<p>Other~~ tall structures.~~</p>~~	+	* Static and dynamic wind loads on tall buildings and skyscrapers.
−	~~<p>Clusters of buildings to determine aerodynamic interference.</p>~~	+	* Static and dynamic wind loads on other tall structures.
−	~~<p>Cladding assemblies.</p>~~	+	* Static and dynamic wind loads on long-span or unusual-shaped roofs.
−	~~<p>Long~~-span or unusual-shaped roofs.~~</p>~~	+	* Static and dynamic wind loads on long-span bridges
−	~~<p>Long-span bridges.</p>~~	+	* Static and dynamic wind loads on building elements, cladding, fixtures.
−	~~<p>Typically, wind tunnel testing is usually undertaken during the early planning stages and where the building:</p>~~	+	* Dispersion studies of contaminants in built up areas and complex topography
−	~~<p>Is over 22-storeys in height (or 10 storeys if in a hurricane zone).</p>~~	+	* Studies of wind comfort around buildings and wind climate in cities
−	~~<p>Has an unusual geometry or construction.</p>~~	+	* Analysis and optimisation of external flows and impacts on internal flows and ventilation
−	~~<p>May be adversely affected by surrounding structures.</p>~~	+	* Studies of building integrated wind power
−	~~<p>Is located amid unusual terrain.</p></li>~~	+	* Relevance of future climate scenarios
−	~~<li>~~Static and dynamic wind loads on ~~building structures</li>~~	+
−	~~<li>~~Static and dynamic wind loads on building elements, cladding, fixtures.~~</li>~~	+	= Related articles on Designing Buildings =
−	~~<li>~~Dispersion of contaminants in built up areas and complex topography~~</li>~~	+
−	~~<li>Wind~~ comfort around buildings and wind climate in cities~~</li>~~	+	* CFD.
−	~~<li>~~Analysis and ~~optimization~~ of internal flows and ventilation~~</li>~~	+	* Computational fluid dynamics in building design: An introduction FB 69.
−	~~<li>Building~~ integrated wind power~~</li>~~	+	* Computational fluid dynamics and urban planning.
−	~~<li>~~Relevance of future climate scenarios~~</li></ul>~~	+	* CN Tower.
		+	* Empire State Building.
		+	* Future climate models.
		+	* Integrating CFD into the design process.
		+	* Petronas Twin Towers.
		+	* Skyscraper.
		+	* Structural principles.
		+	* Taipei 101.
		+	* Tallest buildings in the world.
		+	* The Shard.
		+	* Tower.
		+	* Wind adjacent to tall buildings.
		+	* Wind tunnels.

−	[[Category:~~Articles_needing_more_work~~]]	+	[[Category:DCN_Commentary]] [[Category:DCN_Definition]] [[Category:DCN_Product_Knowledge]] [[Category:DCN_Project_Knowledge]] [[Category:DCN_Research,_Development_and_Innovation]] [[Category:DCN_Software]] [[Category:Definitions]] [[Category:History]] [[Category:Projects_and_case_studies]] [[Category:Research_/_Innovation]] [[Category:Theory]] [[Category:Health_and_safety_/_CDM]] [[Category:Regulations]] [[Category:Standards_/_measurements]] [[Category:Sustainability]]

Editor at 10:33, 21 September 2022

2022-09-21T10:33:26Z

← Older revision		Revision as of 10:33, 21 September 2022
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	Sometime later in 1965 at Ferrybridge in England cooling towers collapsed because of what was later described as a group effect, in that building structures in a group under wind loads behaved diametrically opposite to how they might have behaved individually. This was an example of the aerodynamic group effect of surroundings, very much like the localised built environment surrounding buildings.		Sometime later in 1965 at Ferrybridge in England cooling towers collapsed because of what was later described as a group effect, in that building structures in a group under wind loads behaved diametrically opposite to how they might have behaved individually. This was an example of the aerodynamic group effect of surroundings, very much like the localised built environment surrounding buildings.

−	Finally in 2009 a seven km long section of the bridge over the river Volga in Volgograd, Russia was put into operation, it was a section just under 30 km of a continuous beam composite steel-concrete bridge. One section of the bridge around 1 km long started oscillating with amplitudes of up to 1 m, the cause again was wind, but in this kind of concrete hybrid bridge ( as opposed to a suspension bridge) this kind of movement had never been seen before.	+	Finally in 2009 a seven km long section of the bridge over the river Volga in Volgograd, Russia was put into operation, it was a section just under 30 km of a continuous beam composite steel-concrete bridge. One section of the bridge around 1 km long started oscillating with amplitudes of up to 1 m, the cause again was wind, but in this kind of concrete hybrid bridge ( as opposed to a suspension bridge) this kind of movement had never been seen before. Video footage of the [https://youtu.be/uWP5d2t2JVE moving bridge can be found here.]

	= Brief history of aerodynamics in buildings =		= Brief history of aerodynamics in buildings =
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	Ludwig Prandtl, the founder of fluid dynamics and the boundary layer theory, with the Aerodynamical Experimental Station in Göttinger and the Kaiser Wilhelm Institute for Fluid Dynamics developed the fundamentals of current techniques of aerodynamics. Experiments at this time, were performed in flows with low turbulence, and without boundary layers, and the need to model the atmospheric turbulence properly lead to the design of so called Atmospheric Boundary Layer Wind Tunnels. Recognised in the 1950s, this led to longer working sections of wind tunnels in which experiments with the wind loads on buildings were performed.		Ludwig Prandtl, the founder of fluid dynamics and the boundary layer theory, with the Aerodynamical Experimental Station in Göttinger and the Kaiser Wilhelm Institute for Fluid Dynamics developed the fundamentals of current techniques of aerodynamics. Experiments at this time, were performed in flows with low turbulence, and without boundary layers, and the need to model the atmospheric turbulence properly lead to the design of so called Atmospheric Boundary Layer Wind Tunnels. Recognised in the 1950s, this led to longer working sections of wind tunnels in which experiments with the wind loads on buildings were performed.

−	The impact of the Ferrybridge cooling towers collapse in 1965 and what was accepted as the aerodynamic group effect, lead to further studies of aerodynamic effects on buildings, especially as heights increased and loads changed. The impacts of the aeroelastic effect which impacted the various suspension bridges that had been built, ~~gradully saw~~ aerodynamic study being carried on a number of major projects.	+	The impact of the Ferrybridge cooling towers collapse in 1965 and what was accepted as the aerodynamic group effect, lead to further studies of aerodynamic effects on buildings, especially as heights increased and loads changed. However the phenomenon had been studied some in the early 1900s by the Hungarian physicist Theodore von Kármán, who was investigating why bridge supports and buildings vibrate in high winds. He found that air flowing around an obstacle broke away into distinct whirlwinds, at a certain wind speeds, the forces involved produce resonance, causing wires to sing in the wind, or towers to wobble and in the case of Ferry bridge to collapse..
		+
		+	The impacts of the aeroelastic effect which had impacted the various suspension bridges that had been built, gradually highlighted the importance aerodynamic study being carried on a number of major projects.

	In physics and engineering, both aerodynamics and fluid dynamics as well as hydrodynamics are considered subdisciplines of fluid mechanics that describes the flow of fluids—liquids and gases. The first scientific paper that used a 3D model in fluid flow problems was published by John Hess and A.M.O. Smith in 1967 and marked the birth of what is known as Computational Fluid Dynamics (CFD) which is the digital form of aerodynamic analysis. It allowed aerodynamicists to gain a more detailed understandings of flow fields around or through objects and in particular helped in the modelling of larger objects that could not be modelled directly iin wind tunnels, such as buildings.		In physics and engineering, both aerodynamics and fluid dynamics as well as hydrodynamics are considered subdisciplines of fluid mechanics that describes the flow of fluids—liquids and gases. The first scientific paper that used a 3D model in fluid flow problems was published by John Hess and A.M.O. Smith in 1967 and marked the birth of what is known as Computational Fluid Dynamics (CFD) which is the digital form of aerodynamic analysis. It allowed aerodynamicists to gain a more detailed understandings of flow fields around or through objects and in particular helped in the modelling of larger objects that could not be modelled directly iin wind tunnels, such as buildings.

Editor at 10:22, 21 September 2022

2022-09-21T10:22:41Z

← Older revision		Revision as of 10:22, 21 September 2022
Line 1:		Line 1:
−	[[File:~~Langley Field near Hampton~~, ~~Virginia~~.jpg]]	+	[[File:Langley_Field_near_Hampton%2C_Virginia.jpg\|link=File:Langley_Field_near_Hampton,_Virginia.jpg]]

	The word aerodynamics combines aero meaning air, atmosphere or gases, from the Greek aero or lower atmosphere and dynamic, relating to mechanical forces not in equilibrium from the Greek dynamikos meaning powerful.		The word aerodynamics combines aero meaning air, atmosphere or gases, from the Greek aero or lower atmosphere and dynamic, relating to mechanical forces not in equilibrium from the Greek dynamikos meaning powerful.
Line 7:		Line 7:
	Aerodynamics have been a natural consideration in the construction of sailing boats and windmills for many years, whilst aerodynamic concepts date back to Aristotle and Archimedes in the 2nd and 3rd centuries BC. Sir Isaac Newton was the first to develop a theory of air resistance in the early 1700's, expanded some years later in Hydrodynamica which describes the relationships between pressure, density, and flow velocity, known as Bernoulli's principle after its author, it also provides a method to calculate aerodynamic lift.		Aerodynamics have been a natural consideration in the construction of sailing boats and windmills for many years, whilst aerodynamic concepts date back to Aristotle and Archimedes in the 2nd and 3rd centuries BC. Sir Isaac Newton was the first to develop a theory of air resistance in the early 1700's, expanded some years later in Hydrodynamica which describes the relationships between pressure, density, and flow velocity, known as Bernoulli's principle after its author, it also provides a method to calculate aerodynamic lift.

−	[[File:~~HYDRODYNAMICA Bernoulli~~.jpg]]	+	[[File:HYDRODYNAMICA_Bernoulli.jpg\|link=File:HYDRODYNAMICA_Bernoulli.jpg]]

	= Brief history of aerodynamics in flight =		= Brief history of aerodynamics in flight =
Line 13:		Line 13:
	It was at the turn of the next century that Sir George Cayley identified the inter-related aerodynamic forces of flight as being, weight, lift, drag, and thrust, whilst towards the end of the century Francis Herbert Wenham constructed the first wind tunnel, allowing precise measurements of aerodynamic forces. Aerodynamic principles were then first put into practice in 1871 by the French inventor, Alphonse Pénaud with his model aeroplane called the Planophore, the first aerodynamically stable flying mode with a wind up rear propeller.		It was at the turn of the next century that Sir George Cayley identified the inter-related aerodynamic forces of flight as being, weight, lift, drag, and thrust, whilst towards the end of the century Francis Herbert Wenham constructed the first wind tunnel, allowing precise measurements of aerodynamic forces. Aerodynamic principles were then first put into practice in 1871 by the French inventor, Alphonse Pénaud with his model aeroplane called the Planophore, the first aerodynamically stable flying mode with a wind up rear propeller.

−	[[File:Penaud'~~s Planophore~~.jpg]]	+	[[File:Penaud's_Planophore.jpg\|link=File:Penaud's_Planophore.jpg]]

−	In the years prior to their historic flight of 1903 the Wright brothers themselves built a small, 6-foot-long wind tunnel to test scale models of wing sections before embarking on their first sustained flight by a manned heavier-than-air powered and controlled aircraft in the Wright Flyer (or Kitty Hawk). ~~Although this now represents~~ the early beginnings of the aviation industry, ~~it was~~ some 30 years later ~~that~~ the first full-scale wind tunnel building was able to test the aerodynamics of flight on the ground. At Langley Field near Hampton, Virginia a 9x18 metre aerodynamic test centre was built in the 30's, testing World War II fighters and space capsules to submarines and jets.	+	In the years prior to their historic flight of 1903 the Wright brothers themselves built a small, 6-foot-long wind tunnel to test scale models of wing sections before embarking on their first sustained flight by a manned heavier-than-air powered and controlled aircraft in the Wright Flyer (or Kitty Hawk).
		+
		+	Gustave Eiffel built the first open-return wind tunnel in 1909, at Champs-de-Mars, near the foot of the tower that bears his name, it ran about 4,000 tests up to 1912, setting new standards for aeronautical research. In 1907 the relationship between fluid dynamics and aerodynamics became clearer with the foundation of an experimental facility by Ludwig Prandtl, who was considered the founder of fluid dynamics. He built the first Göttinger type of wind tunnel, which unlike Eiffel's wind tunnel featured a closed cycle for liquids or gases to flow in and was the starting point of the later Aerodynamical Experimental Station founded in Göttinger in 1915.
		+
		+	As the early beginnings of the aviation industry had commenced, some 15 years later the first full-scale wind tunnel building was constructed and able to test the aerodynamics of flight on the ground. At Langley Field near Hampton, Virginia a 9x18 metre aerodynamic test centre was built in the 30's, testing World War II fighters and space capsules to submarines and jets.
		+
		+	The wind tunnel played a major role during the Second World War and saw further development for the testing of supersonic aircraft during the Cold War. It has developed largely in parallel with the development of aircraft generally as well as in time the aerodynamics of buildings.

	= Brief history of aerodynamics in structures =		= Brief history of aerodynamics in structures =
Line 21:		Line 27:
	Aerodynamics only really started to be considered for fixed objects though the construction and subsequent failure of a number of large structures. The first, most significant and most dramatic failure was that of the Tacoma Narrows Bridge built in the USA in 1940, which had a span of over 1,645 metres and shortly after opening became known as Galloping Gertie due to the movement of it deck. About 5 months after completion, as wind speeds in the area picked up to around 40 miles an hour, the wave movements of the deck increased and as the public watched from the shore the bridge eventually collapsed. As it took such a long time and withheld such movements the extraordinary event was actually captured on film and can be watched [https://www.youtube.com/watch?v=GBa_USozxFM here as a silent fim recording.]		Aerodynamics only really started to be considered for fixed objects though the construction and subsequent failure of a number of large structures. The first, most significant and most dramatic failure was that of the Tacoma Narrows Bridge built in the USA in 1940, which had a span of over 1,645 metres and shortly after opening became known as Galloping Gertie due to the movement of it deck. About 5 months after completion, as wind speeds in the area picked up to around 40 miles an hour, the wave movements of the deck increased and as the public watched from the shore the bridge eventually collapsed. As it took such a long time and withheld such movements the extraordinary event was actually captured on film and can be watched [https://www.youtube.com/watch?v=GBa_USozxFM here as a silent fim recording.]

−	[[File:~~Tacoma Narrows Bridge Falling~~.jpg]]	+	[[File:Tacoma_Narrows_Bridge_Falling.jpg\|link=File:Tacoma_Narrows_Bridge_Falling.jpg]]
		+
		+	Similar issues were found with the The Bronx–Whitestone suspension Bridge (or Whitestone Bridge) in New York City, and opened in 1939, as a result extra stiffening trusses were added around the same time as the Tacoma Narrows Bridge collapse and it was widened to six lanes. Likewise the The Deer Isle suspension bridge in the state of Maine, also completed in 1939 and also encountered wind stability problems, was modified with cable stays connecting cables to the tower and tower to the deck as a result of what happened in Tacoma.

	Sometime later in 1965 at Ferrybridge in England cooling towers collapsed because of what was later described as a group effect, in that building structures in a group under wind loads behaved diametrically opposite to how they might have behaved individually. This was an example of the aerodynamic group effect of surroundings, very much like the localised built environment surrounding buildings.		Sometime later in 1965 at Ferrybridge in England cooling towers collapsed because of what was later described as a group effect, in that building structures in a group under wind loads behaved diametrically opposite to how they might have behaved individually. This was an example of the aerodynamic group effect of surroundings, very much like the localised built environment surrounding buildings.
Line 29:		Line 37:
	= Brief history of aerodynamics in buildings =		= Brief history of aerodynamics in buildings =

−	[[File:~~Flow experiments by Irminger 1930~~.jpg]]	+	[[File:Flow_experiments_by_Irminger_1930.jpg\|link=File:Flow_experiments_by_Irminger_1930.jpg]]
		+
		+	In the 1930's, working in Denmark, Irminger and Nokkentved, investigated the nature of air movement over buildings, in particular the accuracy of wind-tunnel methods for reproducing the correct air-flow separation and reattachment positions of the vortices formed by winds passing over buildings.
		+
		+	Ludwig Prandtl, the founder of fluid dynamics and the boundary layer theory, with the Aerodynamical Experimental Station in Göttinger and the Kaiser Wilhelm Institute for Fluid Dynamics developed the fundamentals of current techniques of aerodynamics. Experiments at this time, were performed in flows with low turbulence, and without boundary layers, and the need to model the atmospheric turbulence properly lead to the design of so called Atmospheric Boundary Layer Wind Tunnels. Recognised in the 1950s, this led to longer working sections of wind tunnels in which experiments with the wind loads on buildings were performed.
		+
		+	The impact of the Ferrybridge cooling towers collapse in 1965 and what was accepted as the aerodynamic group effect, lead to further studies of aerodynamic effects on buildings, especially as heights increased and loads changed. The impacts of the aeroelastic effect which impacted the various suspension bridges that had been built, gradully saw aerodynamic study being carried on a number of major projects.

−	In ~~the 1930's, working in Denmark, Irminger~~ and ~~Nokkentved~~, ~~investigated~~ the ~~nature~~ of ~~air movement over buildings,~~ in ~~particluar~~ the ~~accuracy~~ of ~~wind-tunnel methods for reproducing~~ the ~~correct air-~~flow ~~separation~~ and ~~reattachment positions of~~ the ~~vortices formed by winds passing over~~ buildings.	+	In physics and engineering, both aerodynamics and fluid dynamics as well as hydrodynamics are considered subdisciplines of fluid mechanics that describes the flow of fluids—liquids and gases. The first scientific paper that used a 3D model in fluid flow problems was published by John Hess and A.M.O. Smith in 1967 and marked the birth of what is known as Computational Fluid Dynamics (CFD) which is the digital form of aerodynamic analysis. It allowed aerodynamicists to gain a more detailed understandings of flow fields around or through objects and in particular helped in the modelling of larger objects that could not be modelled directly iin wind tunnels, such as buildings.

	= Aerodynamics in buildings today =		= Aerodynamics in buildings today =

−	* Static and dynamic wind loads on building structures	+	<ul>
−	* Static and dynamic wind loads on building elements, cladding, fixtures.	+	<li><p>Tall buildings and skyscrapers.</p>
−	* Dispersion of contaminants in built up areas and complex topography	+	<p>Other tall structures.</p>
−	* Wind comfort around buildings and wind climate in cities	+	<p>Clusters of buildings to determine aerodynamic interference.</p>
−	* Analysis and optimization of internal flows and ventilation	+	<p>Cladding assemblies.</p>
−	* Building integrated wind power	+	<p>Long-span or unusual-shaped roofs.</p>
−	* Relevance of future climate scenarios	+	<p>Long-span bridges.</p>
		+	<p>Typically, wind tunnel testing is usually undertaken during the early planning stages and where the building:</p>
		+	<p>Is over 22-storeys in height (or 10 storeys if in a hurricane zone).</p>
		+	<p>Has an unusual geometry or construction.</p>
		+	<p>May be adversely affected by surrounding structures.</p>
		+	<p>Is located amid unusual terrain.</p></li>
		+	<li>Static and dynamic wind loads on building structures</li>
		+	<li>Static and dynamic wind loads on building elements, cladding, fixtures.</li>
		+	<li>Dispersion of contaminants in built up areas and complex topography</li>
		+	<li>Wind comfort around buildings and wind climate in cities</li>
		+	<li>Analysis and optimization of internal flows and ventilation</li>
		+	<li>Building integrated wind power</li>
		+	<li>Relevance of future climate scenarios</li></ul>

	[[Category:Articles_needing_more_work]]		[[Category:Articles_needing_more_work]]

Editor at 08:43, 21 September 2022

2022-09-21T08:43:56Z

← Older revision		Revision as of 08:43, 21 September 2022
Line 1:		Line 1:
		+	[[File:Langley Field near Hampton, Virginia.jpg]]
		+
	The word aerodynamics combines aero meaning air, atmosphere or gases, from the Greek aero or lower atmosphere and dynamic, relating to mechanical forces not in equilibrium from the Greek dynamikos meaning powerful.		The word aerodynamics combines aero meaning air, atmosphere or gases, from the Greek aero or lower atmosphere and dynamic, relating to mechanical forces not in equilibrium from the Greek dynamikos meaning powerful.

Line 4:		Line 6:

	Aerodynamics have been a natural consideration in the construction of sailing boats and windmills for many years, whilst aerodynamic concepts date back to Aristotle and Archimedes in the 2nd and 3rd centuries BC. Sir Isaac Newton was the first to develop a theory of air resistance in the early 1700's, expanded some years later in Hydrodynamica which describes the relationships between pressure, density, and flow velocity, known as Bernoulli's principle after its author, it also provides a method to calculate aerodynamic lift.		Aerodynamics have been a natural consideration in the construction of sailing boats and windmills for many years, whilst aerodynamic concepts date back to Aristotle and Archimedes in the 2nd and 3rd centuries BC. Sir Isaac Newton was the first to develop a theory of air resistance in the early 1700's, expanded some years later in Hydrodynamica which describes the relationships between pressure, density, and flow velocity, known as Bernoulli's principle after its author, it also provides a method to calculate aerodynamic lift.
		+
		+	[[File:HYDRODYNAMICA Bernoulli.jpg]]

	= Brief history of aerodynamics in flight =		= Brief history of aerodynamics in flight =

	It was at the turn of the next century that Sir George Cayley identified the inter-related aerodynamic forces of flight as being, weight, lift, drag, and thrust, whilst towards the end of the century Francis Herbert Wenham constructed the first wind tunnel, allowing precise measurements of aerodynamic forces. Aerodynamic principles were then first put into practice in 1871 by the French inventor, Alphonse Pénaud with his model aeroplane called the Planophore, the first aerodynamically stable flying mode with a wind up rear propeller.		It was at the turn of the next century that Sir George Cayley identified the inter-related aerodynamic forces of flight as being, weight, lift, drag, and thrust, whilst towards the end of the century Francis Herbert Wenham constructed the first wind tunnel, allowing precise measurements of aerodynamic forces. Aerodynamic principles were then first put into practice in 1871 by the French inventor, Alphonse Pénaud with his model aeroplane called the Planophore, the first aerodynamically stable flying mode with a wind up rear propeller.
		+
		+	[[File:Penaud's Planophore.jpg]]

	In the years prior to their historic flight of 1903 the Wright brothers themselves built a small, 6-foot-long wind tunnel to test scale models of wing sections before embarking on their first sustained flight by a manned heavier-than-air powered and controlled aircraft in the Wright Flyer (or Kitty Hawk). Although this now represents the early beginnings of the aviation industry, it was some 30 years later that the first full-scale wind tunnel building was able to test the aerodynamics of flight on the ground. At Langley Field near Hampton, Virginia a 9x18 metre aerodynamic test centre was built in the 30's, testing World War II fighters and space capsules to submarines and jets.		In the years prior to their historic flight of 1903 the Wright brothers themselves built a small, 6-foot-long wind tunnel to test scale models of wing sections before embarking on their first sustained flight by a manned heavier-than-air powered and controlled aircraft in the Wright Flyer (or Kitty Hawk). Although this now represents the early beginnings of the aviation industry, it was some 30 years later that the first full-scale wind tunnel building was able to test the aerodynamics of flight on the ground. At Langley Field near Hampton, Virginia a 9x18 metre aerodynamic test centre was built in the 30's, testing World War II fighters and space capsules to submarines and jets.
Line 13:		Line 19:
	= Brief history of aerodynamics in structures =		= Brief history of aerodynamics in structures =

−	Aerodynamics only really started to be considered for fixed objects though the construction and subsequent failure of a number of large structures. The first, most significant and most dramatic failure was that of the Tacoma Narrows Bridge built in the USA in 1940, which had a span of over 1,645 metres and shortly after opening became known as Galloping Gertie due to the movement of it deck. About 5 months after completion, as wind speeds in the area picked up to around 40 miles an hour, the wave movements of the deck increased and as the public watched from the shore the bridge eventually collapsed. As it took such a long time and withheld such movements the ~~extrodinary~~ event was actually captured on film and can be watched [https://www.youtube.com/watch?v=GBa_USozxFM here as a silent fim recording.]	+	Aerodynamics only really started to be considered for fixed objects though the construction and subsequent failure of a number of large structures. The first, most significant and most dramatic failure was that of the Tacoma Narrows Bridge built in the USA in 1940, which had a span of over 1,645 metres and shortly after opening became known as Galloping Gertie due to the movement of it deck. About 5 months after completion, as wind speeds in the area picked up to around 40 miles an hour, the wave movements of the deck increased and as the public watched from the shore the bridge eventually collapsed. As it took such a long time and withheld such movements the extraordinary event was actually captured on film and can be watched [https://www.youtube.com/watch?v=GBa_USozxFM here as a silent fim recording.]

−	Sometime later in 1965 at Ferrybridge in England cooling towers collapsed becasue of what was later described as a group effect, in that building structures in a group under wind loads behaved diametrically opposite to how they might have behaved individually. This was an example of the aerodynamic group effect of surroundings, very much like the localised built environment surrounding buildings.	+	[[File:Tacoma Narrows Bridge Falling.jpg]]

−	Finally in 2009 a seven km long section of the bridge over the river Volga in Volgograd, Russia was put into operation, it was a section just under 30 km of a continuous beam composite steel-concrete bridge. One section of the bridge around 1 km long started oscillating with amplitudes of up to 1 m, the ~~casue~~ again was wind, but in this kind of concrete hybrid bridge ( as opposed to a suspension bridge) this kind of movement had never been seen before.	+	Sometime later in 1965 at Ferrybridge in England cooling towers collapsed because of what was later described as a group effect, in that building structures in a group under wind loads behaved diametrically opposite to how they might have behaved individually. This was an example of the aerodynamic group effect of surroundings, very much like the localised built environment surrounding buildings.
		+
		+	Finally in 2009 a seven km long section of the bridge over the river Volga in Volgograd, Russia was put into operation, it was a section just under 30 km of a continuous beam composite steel-concrete bridge. One section of the bridge around 1 km long started oscillating with amplitudes of up to 1 m, the cause again was wind, but in this kind of concrete hybrid bridge ( as opposed to a suspension bridge) this kind of movement had never been seen before.

	= Brief history of aerodynamics in buildings =		= Brief history of aerodynamics in buildings =

−	In the 1930's, working in Denmark, Irminger and Nokkentved~~[I]~~, investigated the nature of air movement over buildings, in particluar ~~. A large part of their work was concerned with assessing~~ the accuracy of wind-tunnel methods for ~~reproduc- ing~~ the correct air-flow separation and ~~reattach- ment~~ positions of the vortices formed by winds passing over buildings.	+	[[File:Flow experiments by Irminger 1930.jpg]]
		+
		+	In the 1930's, working in Denmark, Irminger and Nokkentved, investigated the nature of air movement over buildings, in particluar the accuracy of wind-tunnel methods for reproducing the correct air-flow separation and reattachment positions of the vortices formed by winds passing over buildings.

	= Aerodynamics in buildings today =		= Aerodynamics in buildings today =

Editor at 08:12, 21 September 2022

2022-09-21T08:12:30Z

← Older revision		Revision as of 08:12, 21 September 2022
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	= Brief history of aerodynamics in flight =		= Brief history of aerodynamics in flight =

−	It was at the turn of the next century that Sir George Cayley identified the inter-related aerodynamic forces of flight as being, weight, lift, drag, and thrust, whilst towards the end of the century Francis Herbert Wenham constructed the first wind tunnel, allowing precise measurements of aerodynamic forces. Aerodynamic principles were first put into practice in ~~the~~ 1871 by the French inventor, Alphonse Pénaud with his model aeroplane called the Planophore, ~~which was~~ the first aerodynamically stable flying ~~model~~. In the 1903 the Wright ~~Flyer (or Kitty Hawk) made the~~ first sustained flight by a manned heavier-than-air powered and controlled aircraft.	+	It was at the turn of the next century that Sir George Cayley identified the inter-related aerodynamic forces of flight as being, weight, lift, drag, and thrust, whilst towards the end of the century Francis Herbert Wenham constructed the first wind tunnel, allowing precise measurements of aerodynamic forces. Aerodynamic principles were then first put into practice in 1871 by the French inventor, Alphonse Pénaud with his model aeroplane called the Planophore, the first aerodynamically stable flying mode with a wind up rear propeller.
		+
		+	In the years prior to their historic flight of 1903 the Wright brothers themselves built a small, 6-foot-long wind tunnel to test scale models of wing sections before embarking on their first sustained flight by a manned heavier-than-air powered and controlled aircraft in the Wright Flyer (or Kitty Hawk). Although this now represents the early beginnings of the aviation industry, it was some 30 years later that the first full-scale wind tunnel building was able to test the aerodynamics of flight on the ground. At Langley Field near Hampton, Virginia a 9x18 metre aerodynamic test centre was built in the 30's, testing World War II fighters and space capsules to submarines and jets.

	= Brief history of aerodynamics in structures =		= Brief history of aerodynamics in structures =
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	= Brief history of aerodynamics in buildings =		= Brief history of aerodynamics in buildings =
		+
		+	In the 1930's, working in Denmark, Irminger and Nokkentved[I], investigated the nature of air movement over buildings, in particluar . A large part of their work was concerned with assessing the accuracy of wind-tunnel methods for reproduc- ing the correct air-flow separation and reattach- ment positions of the vortices formed by winds passing over buildings.

	= Aerodynamics in buildings today =		= Aerodynamics in buildings today =

Editor: Created page with "The word aerodynamics combines aero meaning air, atmosphere or gases, from the Greek aero or lower atmosphere and dynamic, relating to mechanical forces not in equilibrium from t..."

2022-09-20T20:22:29Z

Created page with "The word aerodynamics combines aero meaning air, atmosphere or gases, from the Greek aero or lower atmosphere and dynamic, relating to mechanical forces not in equilibrium from t..."

New page

The word aerodynamics combines aero meaning air, atmosphere or gases, from the Greek aero or lower atmosphere and dynamic, relating to mechanical forces not in equilibrium from the Greek dynamikos meaning powerful.

= Brief history of aerodynamics in theory =

Aerodynamics have been a natural consideration in the construction of sailing boats and windmills for many years, whilst aerodynamic concepts date back to Aristotle and Archimedes in the 2nd and 3rd centuries BC. Sir Isaac Newton was the first to develop a theory of air resistance in the early 1700's, expanded some years later in Hydrodynamica which describes the relationships between pressure, density, and flow velocity, known as Bernoulli's principle after its author, it also provides a method to calculate aerodynamic lift.

= Brief history of aerodynamics in flight =

It was at the turn of the next century that Sir George Cayley identified the inter-related aerodynamic forces of flight as being, weight, lift, drag, and thrust, whilst towards the end of the century Francis Herbert Wenham constructed the first wind tunnel, allowing precise measurements of aerodynamic forces. Aerodynamic principles were first put into practice in the 1871 by the French inventor, Alphonse Pénaud with his model aeroplane called the Planophore, which was the first aerodynamically stable flying model. In the 1903 the Wright Flyer (or Kitty Hawk) made the first sustained flight by a manned heavier-than-air powered and controlled aircraft.

= Brief history of aerodynamics in structures =

Aerodynamics only really started to be considered for fixed objects though the construction and subsequent failure of a number of large structures. The first, most significant and most dramatic failure was that of the Tacoma Narrows Bridge built in the USA in 1940, which had a span of over 1,645 metres and shortly after opening became known as Galloping Gertie due to the movement of it deck. About 5 months after completion, as wind speeds in the area picked up to around 40 miles an hour, the wave movements of the deck increased and as the public watched from the shore the bridge eventually collapsed. As it took such a long time and withheld such movements the extrodinary event was actually captured on film and can be watched [https://www.youtube.com/watch?v=GBa_USozxFM here as a silent fim recording.]

Sometime later in 1965 at Ferrybridge in England cooling towers collapsed becasue of what was later described as a group effect, in that building structures in a group under wind loads behaved diametrically opposite to how they might have behaved individually. This was an example of the aerodynamic group effect of surroundings, very much like the localised built environment surrounding buildings.

Finally in 2009 a seven km long section of the bridge over the river Volga in Volgograd, Russia was put into operation, it was a section just under 30 km of a continuous beam composite steel-concrete bridge. One section of the bridge around 1 km long started oscillating with amplitudes of up to 1 m, the casue again was wind, but in this kind of concrete hybrid bridge ( as opposed to a suspension bridge) this kind of movement had never been seen before.

= Brief history of aerodynamics in buildings =

= Aerodynamics in buildings today =

* Static and dynamic wind loads on building structures
* Static and dynamic wind loads on building elements, cladding, fixtures.
* Dispersion of contaminants in built up areas and complex topography
* Wind comfort around buildings and wind climate in cities
* Analysis and optimization of internal flows and ventilation
* Building integrated wind power
* Relevance of future climate scenarios

[[Category:Articles_needing_more_work]]

← Older revision		Revision as of 12:52, 4 October 2022
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	[[File:Langley_Field_near_Hampton%2C_Virginia.jpg\|link=File:Langley_Field_near_Hampton,_Virginia.jpg]]		[[File:Langley_Field_near_Hampton%2C_Virginia.jpg\|link=File:Langley_Field_near_Hampton,_Virginia.jpg]]

−	The word aerodynamics combines aero meaning air, atmosphere or gases, from the Greek aero or lower atmosphere and dynamic, relating to mechanical forces not in equilibrium from the Greek dynamikos meaning powerful.	+	The word aerodynamics combines 'aero' meaning air, atmosphere or gases, from the Greek aero or lower atmosphere and 'dynamic', relating to mechanical forces not in equilibrium from the Greek dynamikos meaning powerful.

	= Brief history of aerodynamics in theory =		= Brief history of aerodynamics in theory =

−	Aerodynamics have been a ~~natural~~ consideration in the construction of sailing boats and windmills for many years, whilst aerodynamic concepts date back to Aristotle and Archimedes in the 2nd and 3rd centuries BC. Sir Isaac Newton was the first to develop a theory of air resistance in the early 1700's, expanded some years later in Hydrodynamica which describes the relationships between pressure, density, and flow velocity, known as Bernoulli's principle after its author, it also provides a method to calculate aerodynamic lift.	+	Aerodynamics have been a consideration in the construction of sailing boats and windmills for many years, whilst aerodynamic concepts date back to Aristotle and Archimedes in the 2nd and 3rd centuries BC. Sir Isaac Newton was the first to develop a theory of air resistance in the early 1700's, expanded some years later in Hydrodynamica which describes the relationships between pressure, density, and flow velocity, known as Bernoulli's principle after its author, it also provides a method to calculate aerodynamic lift.

	[[File:HYDRODYNAMICA_Bernoulli.jpg\|link=File:HYDRODYNAMICA_Bernoulli.jpg]]		[[File:HYDRODYNAMICA_Bernoulli.jpg\|link=File:HYDRODYNAMICA_Bernoulli.jpg]]
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	Gustave Eiffel built the first open-return wind tunnel in 1909, at Champs-de-Mars, near the foot of the tower that bears his name, it ran about 4,000 tests up to 1912, setting new standards for aeronautical research. In 1907 the relationship between fluid dynamics and aerodynamics became clearer with the foundation of an experimental facility by Ludwig Prandtl, who was considered the founder of fluid dynamics. He built the first Göttinger type of wind tunnel, which unlike Eiffel's wind tunnel featured a closed cycle for liquids or gases to flow in and was the starting point of the later Aerodynamical Experimental Station founded in Göttinger in 1915.		Gustave Eiffel built the first open-return wind tunnel in 1909, at Champs-de-Mars, near the foot of the tower that bears his name, it ran about 4,000 tests up to 1912, setting new standards for aeronautical research. In 1907 the relationship between fluid dynamics and aerodynamics became clearer with the foundation of an experimental facility by Ludwig Prandtl, who was considered the founder of fluid dynamics. He built the first Göttinger type of wind tunnel, which unlike Eiffel's wind tunnel featured a closed cycle for liquids or gases to flow in and was the starting point of the later Aerodynamical Experimental Station founded in Göttinger in 1915.

−	As the early beginnings of the aviation industry had commenced, some 15 years later the first full-scale wind tunnel building was constructed and able to test the aerodynamics of flight on the ground. At Langley Field near Hampton, Virginia a 9x18 metre aerodynamic test centre was built in the 30's, testing World War II fighters and space capsules to submarines and jets.	+	As the early beginnings of the aviation industry had commenced, some 15 years later the first full-scale wind tunnel building was constructed and able to test the aerodynamics of flight on the ground. At Langley Field near Hampton, Virginia a 9x18 metre aerodynamic test centre was built in the 1930's, testing World War II fighters and space capsules to submarines and jets.

−	The wind tunnel played a major role during the Second World War and saw further development for the testing of supersonic aircraft during the Cold War. It has developed largely in parallel with the development of aircraft generally ~~as well as in time~~ the aerodynamics of buildings.	+	The wind tunnel played a major role during the Second World War and saw further development for the testing of supersonic aircraft during the Cold War. It has developed largely in parallel with the development of aircraft generally, and later the aerodynamics of buildings.

	= Brief history of aerodynamics in structures =		= Brief history of aerodynamics in structures =

−	Aerodynamics only really started to be considered for fixed objects ~~though~~ the construction and subsequent failure of a number of large structures. The first, most significant and most dramatic failure was that of the Tacoma Narrows Bridge built in the USA in 1940, which had a span of over 1,645 metres and shortly after opening became known as Galloping Gertie due to the movement of it deck. About 5 months after completion, as wind speeds in the area picked up to around 40 miles an hour, the wave movements of the deck increased and as the public watched from the shore the bridge eventually collapsed. As it took such a long time and withheld such movements the extraordinary event was actually captured on film and can be watched [https://www.youtube.com/watch?v=GBa_USozxFM here as a silent fim recording.]	+	Aerodynamics only really started to be considered for fixed objects following the construction and subsequent failure of a number of large structures. The first, most significant and most dramatic failure was that of the Tacoma Narrows Bridge built in the USA in 1940, which had a span of over 1,645 metres and shortly after opening became known as Galloping Gertie due to the movement of its deck. About 5 months after completion, as wind speeds in the area picked up to around 40 miles an hour, the wave movements of the deck increased and as the public watched from the shore the bridge eventually collapsed. As it took such a long time and withheld such movements the extraordinary event was actually captured on film and can be watched [https://www.youtube.com/watch?v=GBa_USozxFM here as a silent fim recording.]

	[[File:Tacoma_Narrows_Bridge_Falling.jpg\|link=File:Tacoma_Narrows_Bridge_Falling.jpg]]		[[File:Tacoma_Narrows_Bridge_Falling.jpg\|link=File:Tacoma_Narrows_Bridge_Falling.jpg]]

−	Similar issues were found with the The Bronx–Whitestone suspension Bridge (or Whitestone Bridge) in New York City, ~~and~~ opened in 1939~~, as~~ a result extra stiffening trusses were added around the same time as the Tacoma Narrows Bridge collapse and it was widened to six lanes. Likewise the The Deer Isle suspension bridge in the state of Maine, also completed in 1939 ~~and also~~ encountered wind stability problems, was modified with cable stays connecting cables to the tower and tower to the deck as a result of what happened in Tacoma.	+	Similar issues were found with the The Bronx–Whitestone suspension Bridge (or Whitestone Bridge) in New York City, opened in 1939. As a result. extra stiffening trusses were added around the same time as the Tacoma Narrows Bridge collapse and it was widened to six lanes. Likewise the The Deer Isle suspension bridge in the state of Maine, also completed in 1939 encountered wind stability problems, and was modified with cable stays connecting cables to the tower and tower to the deck as a result of what happened in Tacoma.

	Sometime later in 1965 at Ferrybridge in England cooling towers collapsed because of what was later described as a group effect, in that building structures in a group under wind loads behaved diametrically opposite to how they might have behaved individually. This was an example of the aerodynamic group effect of surroundings, very much like the localised built environment surrounding buildings.		Sometime later in 1965 at Ferrybridge in England cooling towers collapsed because of what was later described as a group effect, in that building structures in a group under wind loads behaved diametrically opposite to how they might have behaved individually. This was an example of the aerodynamic group effect of surroundings, very much like the localised built environment surrounding buildings.
		+
		+	The Millennium Bridge in London, opened in 2000, had similar problems and was nicknames the Wobbly Bridge. Its oscilation was corrected by the addition of mass dampers.

	Finally in 2009 a seven km long section of the bridge over the river Volga in Volgograd, Russia was put into operation, it was a section just under 30 km of a continuous beam composite steel-concrete bridge. One section of the bridge around 1 km long started oscillating with amplitudes of up to 1 m, the cause again was wind, but in this kind of concrete hybrid bridge ( as opposed to a suspension bridge) this kind of movement had never been seen before. Video footage of the [https://youtu.be/uWP5d2t2JVE moving bridge can be found here.]		Finally in 2009 a seven km long section of the bridge over the river Volga in Volgograd, Russia was put into operation, it was a section just under 30 km of a continuous beam composite steel-concrete bridge. One section of the bridge around 1 km long started oscillating with amplitudes of up to 1 m, the cause again was wind, but in this kind of concrete hybrid bridge ( as opposed to a suspension bridge) this kind of movement had never been seen before. Video footage of the [https://youtu.be/uWP5d2t2JVE moving bridge can be found here.]