液压自由活塞发动机能量转换效率研究

以提高系统总效率为目标,研究了单活塞式自由活塞柴油液压动力装置的节能途径.分析了系统的能量传递过程,理论计算了能量输入、损失和输出之间的关系,结合试验结果研究了系统各组成部分的节能途径.结果表明:系统最高效率理论值可达38%,样机实测值为27.5%.理论和试验结果都表明系统总效率明显优于内燃机与液压泵的传统组合.系统内燃机部分的指示热效率达到传统内燃机的较优水平.系统液压泵部分泵腔效率的提高通过提高吸排油阀动态响应实现,高压腔和压缩腔循环效率提高通过减小两腔节流损失实现. 

Energy Conversion Efficiency of Hydraulic Free Piston Engine

To improve total efficiency of a single hydraulic free piston diesel engine, the energy saving methods were studied. The power transmission process was analysed. The relation between input, lost and output energy were calculated. The energy saving approach for system components was analysed with experimental results. The results indicate that the system efficiency reaches about 38% in theory. The measured system efficiency of the prototype is about 27.5%. The theory and experimental results indicate that the system efficiency is higher than that of the conventional assemble of internal-combustion engine and hydraulic pump. The indicated thermal efficiency of the internal-combustion engine part is closed to the high level of the conventional. Higher dynamic response valves can improve the pump chamber efficiency of the hydraulic pump part. Smaller throttle effects can increase the circular efficiency of the high-pressure and compression chamber.