This analysis derives an expression for the thrust of a non-ideal supersonic conical nozzle in terms of coefficients that can be measured experimentally. The coefficients chosen are discharge coefficients pressure coefficient, and the geometric divergence coefficient.
Expressions are developed for the gas velocity, the area ratio and the thrust in terms of the pressure ratio, the specific heat ratio, and the above coefficients.
Optimum operating conditions are deduced and it is shown that the jet exit pressure should be greater than atmospheric for maximum thrust. The proposed equation is in good agreement with observed results.
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