空气源NTP喷射系统再生EGR冷却器试验研究

Experimental Study of EGR Cooler Regeneration by Air-fed NTP Injection System

以压缩空气为气源,建立了低温等离子体（NTP）喷射系统再生废气再循环（EGR）冷却器的试验系统,在不同的再生温度下进行EGR冷却器的再生试验,通过测量再生过程中主要活性物质（NO2、O3）以及再生产物COx的变化情况,分析了再生温度对EGR冷却器再生的影响。试验结果表明：空气源NTP能在18-300℃的温度范围内实现EGR冷却器再生。再生过程中,O3和NO2均随着温度的升高而降低,在150℃时被完全消耗。再生过程产生的CO较少,故C1（CO中C的质量）的值较小,占C12（COx中C的质量）的比例不足1/8。而C2（CO2中C的质量）与C12的趋势趋于一致,均随着温度的升高先增加后减小,当再生温度为150℃时,C2和C12均达到较大值。当再生温度为150℃时,NTP产生的活性物质的利用率较高,去除积碳量较多,再生效果较好。

Using air as the gas source,the regeneration system of exhaust gas recirculation（ EGR） cooler was built to do an experimental study at 18℃,60℃,90℃,120℃,150℃,200℃ and 300℃,which was based on non-thermal plasma（ NTP） injection system. The influence of temperature on regeneration was investigated by measuring the volume fraction of main active substance（ O3,NO2） and regeneration products（ COx）. The results indicate that CO and CO2 can be detected all the time,which means that the EGR cooler can be regenerated by air-fed NTP at a wide temperature range of 18 - 300℃. In the process of regeneration,the volume fractions of O3 and NO2show drop trends with the increasing temperature,and they are completely consumed when the temperature is 150℃. And the concentration of NOxdecreases obviously firstly and then increases slightly with the rising temperature and gets a low level when temperature is above 90℃. Therefore, the temperature should be controlled at 150℃ in consideration of active substance utilization and NOxcontrol. Additionally,little CO is produced,so that C1（ the mass of C in CO） in C12（ the mass of C in COx） is less than 1 /8. However,much CO2 is generated and remains relatively stable with the regeneration time. Besides,the trend of C2（ the mass of C in CO2） and C12 are almost same,they are all rising firstly and then dropping with the rising temperature,furthermore,they get the peak at 150℃. In total,the efficiency of main active substance which is generated by NTP reactor,is higher,the more carbon deposition is removed and the regenerative effect is more remarkable,when the regeneration temperature is 150℃.