Nozzle Design Analysis under Friction-existing Condition

Critical pressure calculation is the key to nozzledesign.The critical pressure when gas flow through nozzle under friction-existing condition is different from that under reversable heat- insu1ated conditions.This paper presents a new view point that nozzle has an actual critical pressure with friction in existence, and derives the formulas to calculate the actual critical pressure. Several other problems in nozzle design under friction-existing condition are also discussed.