Channel Flow of a Compressible Fluid
MAE130B
Concept/Question/Comments
Film: Channel Flow of a Compressible Fluid
Due Date: March 15, 2013
Concept 1: Choking
Choking occurs when the Mach number at the throat of a channel flow is equal to one. Conceptually choking is the phenomena where the flow in a channel transitions to sonic flow. Due to the conditions of choking, the velocity, density, and pressure can increase or decrease continuously through a sonic throat, and the flow does not need to be symmetrical. Another notable phenomena is that the maximum velocity does not need to occur at the throat of the channel flow.
Concept 2: Blocking
Blocking occurs when both throats of the channel flow are experiencing choking. Under these circumstances, the second throat does cannot affect the first shock wave with the control valve, and the first shock wave becomes trapped in the supersonic nozzle. As a result of these conditions, the Mach number of the supersonic flow entering the shock wave increases, and the dissipation of energy in the shock wave also increases.
Concept 3: Starting
In order to avoid blocking from occurring in the channel flow, the second throat must be opened more to decrease the backpressure inside of the channel. Starting, sometimes referred to as running, occurs when the lack of backpressure created in the channel forces the shockwave inside the channel to suddenly jump through the second throat to the sonic diffuser. Since the second throat essentially swallows the original shock wave, it can be inferred that the flow is now supersonic from the first throat to the terminal shock wave.
Question: Would any of these phenomena or evaluations differ if the speed of the water was exceptionally faster than the speed of
Concept/Question/Comments
Film: Channel Flow of a Compressible Fluid
Due Date: March 15, 2013
Concept 1: Choking
Choking occurs when the Mach number at the throat of a channel flow is equal to one. Conceptually choking is the phenomena where the flow in a channel transitions to sonic flow. Due to the conditions of choking, the velocity, density, and pressure can increase or decrease continuously through a sonic throat, and the flow does not need to be symmetrical. Another notable phenomena is that the maximum velocity does not need to occur at the throat of the channel flow.
Concept 2: Blocking
Blocking occurs when both throats of the channel flow are experiencing choking. Under these circumstances, the second throat does cannot affect the first shock wave with the control valve, and the first shock wave becomes trapped in the supersonic nozzle. As a result of these conditions, the Mach number of the supersonic flow entering the shock wave increases, and the dissipation of energy in the shock wave also increases.
Concept 3: Starting
In order to avoid blocking from occurring in the channel flow, the second throat must be opened more to decrease the backpressure inside of the channel. Starting, sometimes referred to as running, occurs when the lack of backpressure created in the channel forces the shockwave inside the channel to suddenly jump through the second throat to the sonic diffuser. Since the second throat essentially swallows the original shock wave, it can be inferred that the flow is now supersonic from the first throat to the terminal shock wave.
Question: Would any of these phenomena or evaluations differ if the speed of the water was exceptionally faster than the speed of