Flow Quality Impact on airfoil pressure distribution

[iamvksaini]

I have collected velocity data for a 3-D grid of test section of a low speed wind tunnel.I have tested airfoils for pressure distribution in the same test section for similar free stream conditions. How do I calculate the impact of flow quality in the test section on the test results of pressure distribution on airfoil surface?

 

[Aaron Barnard]

The impact of flow quality on the test results of pressure distribution on airfoil surface can be calculated by performing a Computational Fluid Dynamics (CFD) analysis. CFD can be used to simulate the flow characteristics of the wind tunnel test section and compare the velocity values with the measured values. This comparison will provide an indication of how accurately the test section is representing the real-world flow conditions. By comparing the simulated pressure distribution on the airfoil surface with the measured pressure distribution, the impact of flow quality on the test results can be determined.

 

[NatSusan]

There are a few different factors that could impact the flow quality in the test section and therefore affect the pressure distribution results on the airfoil surface. Some potential things to consider are:

1. Turbulence levels: If the flow in the test section is highly turbulent, this could affect the pressure distribution on the airfoil surface. Turbulence can cause fluctuations in the flow that could impact the accuracy of the pressure measurements. You may want to look into ways to reduce turbulence in the test section, such as using screens or flow straighteners.

2. Boundary layer effects: The boundary layer on the walls of the test section can also affect the flow quality and therefore the pressure distribution on the airfoil. If the boundary layer is thick or turbulent, it could cause disturbances in the flow that could impact the results. Consider ways to control the boundary layer, such as using suction or blowing.

3. Blockage effects: The size and shape of the test section can also impact the flow quality. If the test section is too small or if there are obstructions in the flow, it could cause blockage and affect the pressure distribution. Make sure the test section is properly sized and free from any obstructions.

To calculate the impact of these factors on the pressure distribution results, you could try running simulations using different turbulence levels, boundary layer conditions, and test section sizes. This could give you an idea of how much these factors are affecting your results and help you determine the best conditions for accurate pressure measurements. Additionally, you could also compare your results to data from other tests or experiments with similar conditions to see if there are any discrepancies that could be attributed to flow quality.