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

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: ① the 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. ② While 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: ① compared 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; ② Compare 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; ③ The 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); ④ The outlet temperature of the spraying exhaust gas treatment tank is less than 70℃, which meets the requirements of "coal mine safety regulations". © 2019, Editorial Office of Journal of China Coal Society. All right reserved.