When a Compression Ratio curve is entered, the Reference Inlet Conditions are needed for Arrow Solver to convert the Compression Ratio curve from the curve created at the reference conditions (by the vendor) to a curve applicable at the piping system’s operating conditions. The Reference Inlet Conditions are the conditions measured at the inlet of the compressor when the Compression Ratio curve is developed by the curve vendor.

The Reference Inlet Conditions are air at ISO conditions (14.7 psia & 59 deg. F) by default. However, the Reference Inlet Pressure & Temperature can be changed. Currently, air is the only option for the Reference Fluid.