Pressure in Wind Tunnel Test Section

[Sunny1261]

Hello Everyone,
I have a fairly simple wind tunnel question but I cannot seem to connect the pieces.

Homework Statement

Consider a low speed one-circuit wind tunnel with an inlet to throat ratio of 12. The pressure difference between the inlet and the test section was measured to be 10 centimeters of mercury on a U-tube mercury manometer. Calculate the velocity in the tunnel test section. Also, compute the total pressure in the test section.

Homework Equations

What is the pressure?

The Attempt at a Solution

With the aid of Bernoulli's equation and equation of continuity, I was able to determine the velocity in the test area to be 147 m/s. With the equation of continuity, the velocity in the settling chamber is 12.25 m/s.

Using this, I'm able to solve about 1/2 of Bernoulli's equation, but I am still left with two pressure terms, and therefore, am unable to solve for the total pressure in the test section.

Thanks.

A hint would be much appreciated,
Sunny

 

[anathema]

Dear Sunny,

Thank you for sharing your question with the forum. It seems like you have made some good progress in solving for the velocity in the test section using Bernoulli's equation and the equation of continuity. However, as you mentioned, there are still two pressure terms left to solve for the total pressure in the test section.

To solve for the total pressure, you can use the concept of total pressure recovery. In a one-circuit wind tunnel, the total pressure at the inlet should be equal to the total pressure at the test section. This means that the total pressure in the test section can be calculated by adding the measured pressure difference (10 cm of mercury) to the total pressure at the inlet.

I hope this helps you solve the rest of the problem. Keep up the good work in your scientific studies!