# 11.4 Isentropic Flow

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In this section a discussion on a steady state flow through a smooth and without an abrupt area change which include converging– diverging nozzle is presented. The isentropic flow models are important because of two main reasons: One, it provides the information about the trends and important parameters. Two, the correction factors can be introduced later to account for deviations from the ideal state.

Fig. 11.4 Flow of a compressible substance (gas) through a converging–diverging nozzle.