煤矿用废气处理箱的数值仿真及试验

Numerical simulation and test of waste gas treatment tank used in coal mine

针对某型煤矿用防爆柴油机的水浴式废气处理箱排气阻力大造成功率下降、动力不足的问题,分析了传统水浴式废气处理箱和2种低阻力喷淋式废气处理箱的结构和工作原理,发现:①传统的水浴式废气处理箱是废气进入冷却水与加热的水蒸气一起被排出;②低阻力喷淋式废气处理箱是水进入废气中被雾化后与废气一起进入废气处理箱中充分进行热交换后被排出。通过流体仿真分析软件和声学仿真软件对传统的水浴式废气处理箱和新设计的2种低阻力喷淋式废气处理箱进行了模拟仿真分析,得出其压力场、温度场和噪声传递损失值,并对仿真结果进行了对比分析。在实验室对装有水浴式废气处理箱和两种低阻力喷淋式废气处理箱的防爆柴油机进行台架试验。试验结果表明:①2种喷淋式废气处理箱比水浴式废气处理箱的排气阻力降低了1/2以上,提高了防爆柴油机的动力性和经济性;②立式喷淋式废气处理箱的整体压力分布比卧式喷淋式废气处理箱均匀,排气阻力比卧式喷淋式废气处理箱低,出口的平均温度比卧式喷淋式废气处理箱低3℃;③防爆柴油机排出尾气的中频噪声在通过废气处理箱后得到了明显的降低,在考虑温度梯度影响因素的情况下尾气噪声通过立式喷淋式废气处理箱的损失平均约为通过水浴式废气处理箱时的3.3倍,为43 dB,尾气噪声通过卧式喷淋式废气处理箱的损失平均约为通过水浴式废气处理箱时的2倍,为25.6 dB;④喷淋式废气处理箱的出口温度均小于70℃,满足《煤矿安全规程》的要求,该方法和技术可为煤矿井下车辆降低尾气排放提供依据。

Aiming at the problems of power reduction and power shortage caused by the large exhaust resistance of the water-bath waste gas treatment tank of a flameproof diesel engine used in a coal mine,firstly,this article theoretically analyzes the structure and working principle of traditional water bath exhaust gas treatment tank and two kinds of low resistance spray type exhaust gas treatment tank.On this basis,the authors reach the follow-ing conclusions:①the work principle of the traditional water bath type exhaust gas treatment tank is that the waste gas enters the cooling water and is expelled along with the heated water vapor.②While the low resistance spray type waste gas treatment tank makes water entering into the waste gas and is atomized,then together with waste gas into the waste gas treatment tank for full heat exchange and then is discharged.Secondly,through a simulation analysis,the pressure field,temperature field and noise transmission loss value,and the simulation results of the traditional water bath exhaust gas treatment tank and the new designed two kinds low-resistance spray exhaust gas treatment tanks by the fluid simulation software and acoustic simulation software are obtained,and these information are compared and analyzed.In the last,a bench test is developed for the flameproof diesel engines equipped with water-bath exhaust gas treatment tank and two kinds of low-resistance spray exhaust gas treatment tank respectively in the laboratory.The test results show that:①compared with the water bath exhaust gas treatment tank,the exhaust resistance of the two kinds of spray exhaust gas treatment tank is reduced by more than 1/2,which improves the dynamic performance and economy of the flameproof diesel engine;②Compare with horizontal spray type exhaust gas treatment tank,the overall pressure distribution of the vertical spray type exhaust gas treatment tank is more uniform,the exhaust resistance is lower,and the average outlet temperature is 3℃lower;③The intermediate frequency noise of exhaust gas from flameproof diesel engine is obviously reduced after passing through the exhaust gas treatment tank.When the temperature gradient factors are taken into account,the average loss of exhaust noise through the vertical spray type exhaust gas treatment tank is about 3.3 times of that through the water bath type exhaust gas treatment tank,which is 43 dB.The average loss of exhaust noise passing through the horizontal spray type exhaust gas treatment tank is about 2 times of that passing through the water bath type exhaust gas treatment tank(25.6 dB);④The outlet temperature of the spraying exhaust gas treatment tank is less than 70℃,which meets the requirements of“coal mine safety regulations”.