1. If there is a throat in a windtunnel, the flow at that point will always be sonic (M = 1)

Question

2. To get a supersonic flow in the test section, there should always be a throat.

Select the answer that matches

Only statement 1 is true

Only statement 2 is true
correct

Both statement 1 and statement 2 are true

Neither statement 1 nor statement 2 is true

Answer 1

The correct answer is: Only statement 2 is true.

Here's the reasoning for both statements:

1. Statement 1 is not necessarily true. While it is true that flow can become sonic (M = 1) at the throat of a converging-diverging nozzle (where the cross-section is the smallest), it does not imply that the flow at that point will always be sonic in all types of wind tunnels. The flow can be subsonic (M < 1) in some setups, particularly if the design does not specifically allow for supersonic flow or if the operating conditions are not appropriate to achieve sonic conditions.

2. Statement 2 is true because to achieve a supersonic flow in the test section of a wind tunnel, a throat (converging section) is necessary. The throat is where the flow accelerates to sonic speed, transitioning from subsonic to supersonic as it moves through the diverging section of the nozzle.

Thus, only statement 2 holds true in a typical wind tunnel scenario.