What PSI Results from an 8 lb Thrust in a Closed Container?

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An RC electric ducted fan engine producing 8 lb of thrust in a closed container generates a pressure based on the force divided by the area of the duct. The pressure calculation depends on the duct's cross-sectional area; for a 4-inch diameter duct, the area is approximately 12.566 in². This results in an internal pressure of about 0.636 psi when the engine runs continuously. The fan acts as a compressor rather than simply blowing air, creating a net pressure differential within the container. Understanding these dynamics is crucial for applications like battery-powered supercharging in vehicles.
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If I have a RC electric ducted fan engine blowing at 8 lb of thrust into a closed container, what PSI would it be inside of the container, (when the engine is runny continuously)?

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Depends on the size of the container and how the stream is captured. For a coherent stream of air hitting a wall, you can take the force and divide by the area.
 
I am basically making a battery powered supercharger for a car. the motor will be fitted into the intake tube.. can you get a rough idea from that?
 
Subaru_STI said:
If I have a RC electric ducted fan engine blowing at 8 lb of thrust into a closed container, what PSI would it be inside of the container, (when the engine is runny continuously)?
Your statement implies that there's a net pressure differential between the contaniner and the outside air that results in 8 lbs of force at the fan. Also, there's no blowing, the ducted fan is acting as a compressor if it's output is going into a closed container. The pressure would be 8 lbs divided by the cross sectional area of the duct containing the fan. If the duct has a diameter of 4 inches, then the area of the duct is pi x r^2 = pi x (2)^2 = 12.566 in^2. Pressure would be 8 lbs / 12.566 in^2 ~= .636 psi.
 
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