During the isentropic expansion of a flow in an ideal choked diverging nozzle:Group of answer choicesThe static pressure is decreasing as the velocity and Mach number decreasesThe static pressure remains constantThe total enthalpy and the static pressure are dropping as the Mach number increasesThe static pressure is decreasing as the velocity and Mach number increases
Question
During the isentropic expansion of a flow in an ideal choked diverging nozzle:Group of answer choicesThe static pressure is decreasing as the velocity and Mach number decreasesThe static pressure remains constantThe total enthalpy and the static pressure are dropping as the Mach number increasesThe static pressure is decreasing as the velocity and Mach number increases
Solution
The correct answer is: The static pressure is decreasing as the velocity and Mach number increases.
Here's why:
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In an ideal choked diverging nozzle, the flow is isentropic, which means there is no heat transfer and the process is reversible.
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The nozzle is choked, which means the Mach number is 1 at the throat of the nozzle. As the flow continues to expand in the diverging section of the nozzle, the Mach number increases beyond 1, i.e., the flow becomes supersonic.
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As the flow expands, the velocity increases. According to Bernoulli's principle, an increase in the speed of the fluid occurs simultaneously with a decrease in pressure.
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Therefore, as the velocity and Mach number increase, the static pressure decreases.
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The total enthalpy remains constant in an isentropic process, it does not drop.
So, the statement "The static pressure is decreasing as the velocity and Mach number increases" is correct.
Similar Questions
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