Efficiency Determination of Turbochargers for Otto-Cycle Engines

For the determination of the isentropic efficiency of turbochargers, the use of the real properties of the medium gives a more accurate efficiency than the use of the idealized, constant, properties. A serious source of errors in turbine-efficiency determination can be the heat loss to the surroundings. A method is described to overcome this problem. The effectiveness of a turbocharger can be easily expressed in the ratio of the boost pressure and the pressure in the exhaust manifold.