Calculating power of a Turbocharger

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Calculating the power of a turbocharger can be approached by analyzing the change in pressure and temperature between atmospheric conditions and the intake manifold. Given an outside temperature of 25°C and a post-compression temperature of 120°C, along with initial and final pressures of 14.7 psi and 24.7 psi respectively, a rough estimate of the turbo's power output can be derived. The discussion highlights that while the volume may be considered constant during compression, the actual air displacement in a four-stroke engine is crucial for accurate calculations. For example, a 2L engine at 5000 RPM displaces approximately 83L of air per second at 15 psi, leading to an estimated power output around 50 kW. Understanding these parameters is essential for evaluating turbocharger performance.
b_dobro
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Hi. My question is about the turbocharger itself and not about the resulting power increase from the added air in the combustion chamber.

Can you calculate the power of a turbo if you have the change in pressure (atmospheric VS. Intake Manifold), and the change in temperature (outside air to intake manifold temp).?

For example, you know the outside temperature is 25 C, the temperature after compression is 120 C. The initial pressure is atmospheric 14.7Psi, and after compression it is 24.7Psi. Volume is constant. Is there a way to find the power of the turbo if it is able to deliver this pressure change at a constant rate?

I'm just looking for a ballpark number, no need to be exact.
 
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I'm sure there's a way to do it although I'm not in a position to figure it out right now, but, are you sure the volume is constant...during compression?
 
I'm guessing the system would be the air intake side of the engine, so volume should remain the same throughout. I don't think the outside volume should be part of the system.
 
Every revolution of a 4 stroke engine, it displaces half of it's displacement. So, a 2L engine moves 1L of air every revolution.

Say you're boosting 15psi at 5000rpm, that's 83L of air at 15psi every second.

I don't know the equation off hand, but however many joules of energy are stored in 83L of air at 15psi above atmospheric should approximately be the wattage the turbo is putting out. It'll probably be some stupid high number around 50kW; Those things pump some serious amounts of air.
 
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