CNG—柴油双燃料电控发动机试验研究

Experimental Research on CNG-Diesel Dual Fuel Electronically Controlled Engine

将高压共轨柴油机改装成CNG—柴油双燃料电控发动机,利用自行开发的快速原型控制系统来控制天然气的燃烧,保证天然气掺烧后发动机的动力性和燃用纯柴油时保持一致。分析了天然气掺烧替代率在不同负荷时对有效热效率和有害排放物(CO,HC,NOx)及烟度的影响。结果表明:天然气掺烧替代率可以达到80%左右;掺烧后的有效热效率在中低负荷时要低于燃用柴油,高负荷时和燃用柴油一致;掺烧后的烟度明显降低,HC排放明显升高。

The high-pressure common rail diesel engine was converted to CNG-Diesel dual fuel electronically controlled engine. The self-developed rapid prototype control system was used to control the combustion of natural gas. The power performance of dual fuel engine kept the same with that of diesel engine. The influences of CNG mixing rate on the effective thermal efficien- cy, harmful exhaust pollutants such as CO, HC and NOx, and smoke were analyzed at different loads. The results show that the mixing rate of natural gas can reach 80%. The effective thermal efficiency of dual fuel is lower than that of diesel at middle and low loads and keeps the same with that of diesel at high loads. In addition, the smoke obviously reduces while the HC emissions increase significantly.