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Transient Gas Flow Facility

transient gas flow instruments
The caged apparatus in the foreground is an experimental field test measure for transient, high-pressure hydrogen flows. It is designed to verify that dispensers used to refuel hydrogen-powered vehicles are operating within specifications. The blue-painted apparatus in the background is part of the transient flow facility.

A compressor is used to pressurize up to twenty-five 40 L gas cylinders to 35 MPa. The cylinders can then be used as a source of rapidly changing gas flow by opening them sequentially to the test section. Alternatively, a pressure regulator and heat exchangers can be applied to provide a stable high pressure gas flow to a meter under test. A calibrated critical flow venturi instrumented with fast response pressure and temperature sensors (< 100 ms) serves as the reference flow meter. This facility has been used to test the performance of flow meters under rapidly changing flow conditions like those found in hydrogen or methane fuel dispensers. It has also been used to test the performance of field test standards that can be used to check gaseous fuel dispensers for accurate billing.

Created May 11, 2016