r 6 Auxiliary Components for Hydraulic Sys (2)For the adiabatic(isentropic)changes The other bounding condition is a reversible adiabatic (isentropic)change which takes place so rapidly that no flow of heat into or out of the gas occurs.The defining relationship is △V Vo三1 -(写 1 (6-3) p (3)For polytropic changes Practically accumulator gas can follow any number of polytropic changed,which is isothermal during accumulating and adiabatic during discharging due to gas expanded.It can be so calculated by 10 Homepage List Upwards Downwards Return Exit Chapter 6 Auxiliary Components for Hydraulic Systems 10 0 0 1 1 1 1 2 1 1 [( ) ( ) ] n n n V V p p p  = − (2)For the adiabatic(isentropic)changes The other bounding condition is a reversible adiabatic (isentropic) change which takes place so rapidly that no flow of heat into or out of the gas occurs. The defining relationship is (3) For polytropic changes Practically accumulator gas can follow any number of polytropic changed, which is isothermal during accumulating and adiabatic during discharging due to gas expanded. It can be so calculated by （6-3）