Experimental And Numerical Study On Combustion Character Of A Tunable Passive Control Pulse Combustor

The efficient use of energy is conducive to social development, Presently, people tend to use fossil fuels such as coal, fossil oil and natural gas more. However,fossil oil is non-renewable,therefore it is an urgent call to find resolution enabling efficient energy use as well as reducing the amount of discharge. Pulsating combustion is a periodic combustion process under some certain acoustic condition,whose combustion characteristic assumes instability,and combustion characteristics within flaming area is periodically relative of time history. Upon the pulsating of the combustion, combustion efficiency gets improved and coefficient of heat transfer increases to a great extent,. the amount of discharge thereby reduces, and mechanism is simpleThis paper focuses on technology controlling thermoacoustic instability, based on the research in the relationship between operational performance of pulsating combustion and excess air coefficient, power and ratio of gas to air, to seize control of pulsating combustion’s operational performance. The conclusions stand as the following:(1) The modification of the Helmholtz-type pulse combustor adds the tunable premix chamber which turn single air intake into multi-stranded air intake. Our aim is to adjust the operating parameters of Helmholtz-type valveless self-excited pulse combustor.The results suggest that it is feasible, if regulate the distribution of air, air excessive coefficient and thermal power during the experimentation.(2) The operating frequency of pulse combustor can be changed by altering excess air coefficient, combustion thermal power and gas rate. With the increase of excess air ratio, operating frequency showed a decreasing trend after the first increase; The increase of gas rate reduced the operating frequency; when the excess air ratio is maintained at 1.4, the operating frequency climbs up as combustor’s thermal power increases(3) Pressure amplitude can be changed in the same way. It increased with the excess air ratio and combustion thermal power; but as the gas input increases, pressure amplitude increases before it decreases and will then increase as a final stage(4)The pressure amplitude of tail pipe declined as it becomes distant from tail pipe inlet.(5)The change of excess air ratio and combustion thermal power affect the emissions of NOx, whose growth increases as excess air ratio and combustion thermal power goes up(6)If taken as a whole,in one cycle, variation in oxygen concentration inhibited the generation amount of NO, the nitrogen concentration promotes it,in this respect,temperature played a milder role as it doesn’t influence it that much. Since the vibration phase of the three factors is different, the effect on the amount of NO also varies at different stages...