Answered

A 15° half-wedge is inserted into a wind tunnel at 0° angle of attack. When the tunnel is operating, the wave angle from the wedge leading edge is 48°. What is the exit-to-throat area ratio of the tunnel nozzle?

Answer :

Explanation:

A typical example of a nozzle is the pump used in a gasoline refilling station. This nozzle shape helps in increasing the speed of an outflow, and controlling its direction and shape.

Thus, when the tunnel is operating, the wave angle from the wedge leading edge is 48°, and to get the exit-to-throat area ratio the nozzle exit area should be divided by the throat area to get the answer.

Answer:

The exit-to-throat area ratio of the tunnel nozzle  [tex]\frac{A}{A^*}[/tex] is 1.556.

Explanation:

From the theta beta m chart when θ° = 15 and β° = 48°, we have M₁ = 1.9

To  find [tex]\frac{A}{A^*}[/tex] we use the formula

[tex]\frac{A}{A*} = \frac{1}{M} [(\frac{2}{k+1})(1+\frac{k-1}{2}M^2)]^{\frac{(k+1)}{[2(k-1)]} }[/tex]

Where

A = Exit area

[tex]A^*[/tex] = Throat area

M = Mach number of flow = M₁ = 1.9

k = 1.4

Therefore

[tex]\frac{A}{A*} = \frac{1}{1.9} [(\frac{2}{1.4+1})(1+\frac{1.4-1}{2}1.9^2)]^{\frac{(1.4+1)}{[2(1.4-1)]} }[/tex]  =      1.556.

From the above the exit-to-throat area ratio of the tunnel nozzle  is derived as

[tex]\frac{A}{A^*}[/tex] = 1.556.

Other Questions