Data underpinning Performance Analysis of a Flexi-Fuel Turbine-Combined Free-Piston Engine Generator

The turbine-combined free-piston engine generator (TCFPEG) is a hybrid machine, generating both mechanical work from the gas turbine and electricity from the linear electric generator for battery charging. In the present study, the system performance of the designed TCFPEG system is predicted using a validated numerical model. A parametric analysis is undertaken based on the influence of the engine load, valve timing, the number of linear generators adopted, and different fuels on the system performance. It is found that when linear electric generators are connected with the free-piston gas turbine, the bottom dead centre, the peak piston velocity, and engine operation frequency are all reduced. Very minimal difference on the in-cylinder pressure and the compressor pressure is observed, while the peak pressure in the bounce chamber is reduced. When coupled with a linear electric generator, the system efficiency can be improved to nearly 50% by optimising engine load and the number of the linear generators adopted in the TCFPEG system. The system is able to be operated with different fuels as the piston is not limited by a mechanical system; the output power and system efficiency are highest when hydrogen is used as the fuel.

涡轮复合自由活塞发动机发电机（TCFPEG）是一种混合动力机械，能够从燃气涡轮机中产生机械功，并从线性电动发电机中产生电能以供电池充电。在本研究中，通过验证的数值模型预测了设计的TCFPEG系统的系统性能。基于发动机负载、阀门时机、采用的线性发电机数量以及不同燃料对系统性能的影响，进行了参数分析。研究发现，当线性电动发电机与自由活塞燃气涡轮机连接时，活塞的下止点、活塞峰值速度和发动机运行频率均有所降低。在气缸压力和压缩机压力方面观察到极小的差异，而缓冲室的峰值压力有所降低。通过与线性电动发电机耦合，通过优化发动机负载和TCFPEG系统中采用的线性发电机数量，系统效率可提升至近50%。由于活塞不受机械系统的限制，该系统能够使用不同的燃料进行操作；当使用氢气作为燃料时，输出功率和系统效率达到最高。