Abstract
With the increase of endurance mileage, 70MPa hydrogen supply systems are used more and more widely, in which pressure reducing valves are the key component. The flow field and the key parameters of 70MPa two-stage pressure reducing valve for hydrogen are studied in this paper. The two-stage pressure reducing valve with cone and flat valves is simplified to two-dimensional model, which is used in condition of high pressure difference with medium of hydrogen gas. Based on NIST real gas model and state equation of modefied Bennedict-Webb-Rubin (BWR), flow field simulation model is developed. A stepwise initialization method for convergence of calculation is proposed in the paper. The numerical simulations for the flow in two-stage pressure reducing valve are carried out. A set of structural parameters is obtained, which is reasonable for 500km hydrogen fuel cell electric bus.
Experimental Analysis of a Small Generator set Operating on Dual Fuel Diesel-Ethanol