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- Please Use A Diagram To Explain What Does The Inboard Section Mean In The Paragraph Don T Just Copy Text From The Int 1 (71.44 KiB) Viewed 29 times
please use a diagram to explain what does the "inboard" section mean in the paragraph. Don't just copy text from the int
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answerhappygod
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please use a diagram to explain what does the "inboard" section mean in the paragraph. Don't just copy text from the int
please use a diagram to explain what does the "inboard" section mean in the paragraph.
Don't just copy text from the internet!
will rate the answer
Reynolds number and turbulence dependence The boundary layer flow of an aerofoil is significantly affected by the transition between laminar and turbulent flow, described using the Reynolds number. The Reynolds number for an aerofoil is usually defined by taking the chord length as the reference length dimension: Re pvc (2.15) and is typically of the order of Re 10'. Although skin friction is higher for turbulent boundary layers, the increased energisation of fluid in a turbulent boundary layer from the freestream means that the flow generally remains attached at higher angles of attack and can help reduce pressure drag, resulting in delayed flow separation and stall of the aerofoil. Consequently, the maximum lift-to-drag ratio of aerofoils is generally increases with Reynolds number up to around Re 22 x 106, above which the effect of Re is reduced. Achieving such high Reynolds numbers are difficult to achieve in wind tunnels and experimental settings, which has led to the use of pressurised wind tunnels and conducting scaled experiments in water. Freestream turbulence also promotes the transition between a laminar to turbulent boundary layer, which can be beneficial for aerodynamic performance by delaying stall. Turbulence intensity is a metric which non-dimensionalises the turbulent kinetic energy k on the mean flow speed V TI (2.16) Whereas the Reynolds number typically increases as a function of radial position (due to the change in incident flow speed V with radius), turbulence intensity tends to decrease with the higher mean incident flow speeds at the rotor tip resulting in lower levels of turbulence intensity than inboard sections
Don't just copy text from the internet!
will rate the answer
Reynolds number and turbulence dependence The boundary layer flow of an aerofoil is significantly affected by the transition between laminar and turbulent flow, described using the Reynolds number. The Reynolds number for an aerofoil is usually defined by taking the chord length as the reference length dimension: Re pvc (2.15) and is typically of the order of Re 10'. Although skin friction is higher for turbulent boundary layers, the increased energisation of fluid in a turbulent boundary layer from the freestream means that the flow generally remains attached at higher angles of attack and can help reduce pressure drag, resulting in delayed flow separation and stall of the aerofoil. Consequently, the maximum lift-to-drag ratio of aerofoils is generally increases with Reynolds number up to around Re 22 x 106, above which the effect of Re is reduced. Achieving such high Reynolds numbers are difficult to achieve in wind tunnels and experimental settings, which has led to the use of pressurised wind tunnels and conducting scaled experiments in water. Freestream turbulence also promotes the transition between a laminar to turbulent boundary layer, which can be beneficial for aerodynamic performance by delaying stall. Turbulence intensity is a metric which non-dimensionalises the turbulent kinetic energy k on the mean flow speed V TI (2.16) Whereas the Reynolds number typically increases as a function of radial position (due to the change in incident flow speed V with radius), turbulence intensity tends to decrease with the higher mean incident flow speeds at the rotor tip resulting in lower levels of turbulence intensity than inboard sections