Zero-carbon and carbon neutral fuels applied on a linear range extender with multi-fuel adaptability

This study employs a combined analytical and numerical approach to examine the multi-fuel adaptability of the linear range extender system(LRE). The operation and performance characteristics of the LRE system was studied when adopting fossil fuels, carbon-neutral fuels, and zero-carbon fuels. The results showed that the peak piston velocity is maximized with gasoline fuel, achieving a velocity of 6.26 m/s, while the maximum average operating velocity with natural gas fuel is recorded at 5.31 m/s. In terms of output power, gasoline fuel also demonstrates superior performance, reaching a peak of 2.83 kW. For carbon-neutral fuels, the dead centre positions exhibit close proximity, with velocity-displacement relationships remaining largely consistent across different carbon-neutral fuel types. Notably, when utilizing dimethyl ether as fuel, both the peak piston velocity (6.48 m/s) and the average operating velocity (5.33 m/s) attain optimal levels. Additionally, under dimethyl ether fuel conditions, the operating frequency, output power, and friction loss power are maximized at 51.36 Hz, 3.14 kW, and 0.160 kW, respectively. The stable operating range of the system is identified as 126–492 N/(m/s) for one profile and 36–122 N/(m/s) for another. In the prototype design phase of the LRE system, achieving multi-fuel adaptability requires careful consideration not only of design parameters that align with the combustion characteristics of the respective fuels but also of the stable operational load range of the system, which is equally critical for optimal performance.