Experiment study and numerical simulation of hydrogen-air mixture combustion

Abstract

Abstract In this paper, hydrogen-air mixture combustion test was carried out with a cylindrical tank which has a diameter of 2 m and a height of 4 m. The ignitor was located at the lower part of the tank and the volume fraction of hydrogen in the mixed gas was 4.33 %, 5.17 %, 7.38 % and 10.02 % respectively. The computational fluid dynamics software Gasflow is used to simulate the experiment. The changes of pressure, gas temperature and hydrogen concentration in the tank after gas ignition were explored. The results show that when the volume fraction of hydrogen is less than 4 % cannot be ignited. When the volume fraction is above 8 %, hydrogen is consumed completely and the temperature and pressure increase significantly. In the process of combustion, the flame propagates upwards and sideways at the same time, but the upward propagation speed is obviously faster. The upward propagation speed of flame is 0.81 m/s when hydrogen concentration is 5.17 %, 7.38 % is 1.31 m/s, and 10.02 % is 2.63 m/s. The horizontal speed of flame is 0.08 m/s, 0.39 m/s and 0.62 m/s respectively.