液压自由活塞发动机活塞运动规律自适应特性的研究

在一台液压自由活塞发动机(HFPE)样机上进行了活塞运动规率的试验。研究表明:活塞的运动规律对于燃烧相位和累积放热量的变动具有自适应性;随着燃烧相位的提前或累积放热量的增大,活塞换向提前,最大升程和压缩比降低;这种自适应性可有效避免均质压燃过程中的爆震与后燃现象,保证缸内最高压力、最大放热速率的稳定,减少指示功的损失。

Research on Self Adaptive Characteristic of Piston Motion of Hydraulic Free Piston Engine

The test on the piston motion of a hydraulic free piston engine prototype was carried out. The result shows that the piston motion and compression ratio are self-adaptive to the variation of the combustion phase and aggregated heat release. The piston reversion is advanced and the maximum movement of the piston and the compression ratio are reduced with the advance of the combustion phase or the increase of aggregated heat release. This self-adaptive characteristic can effectively avoid the post-combustion and detonation phenomenon in homogeneous charge compression ignition combustion process, thus ensuring the stability of the maximum cylinder pressure and the maximum heat release rate, and reducing indicated work loss.