Abstract
A procedure for estimating uncertainty in the hydraulic efficiency of cryogenic turbines is presented. A case study is performed based on the test data from a cryogenic turbine testing facility. The effects of uncertainties in the measurements of temperature, pressure, and generator power on the turbine hydraulic efficiency are studied and the uncertainty in turbine efficiency is estimated to be ±0.20%. About 79% of the uncertainty is determined to come from the uncertainty in generator power measurement. This uncertainty in turbine efficiency is believed to be reasonable and acceptable for the testing of cryogenic turbines.