关键词: 无曲轴；内燃机；热效率；能量转换器；清洁能源

Abstract: At present, the problem of improving the thermal efficiency of vehicle internal combustion engine is still one of the main contents of vehicle research. In this paper, a new internal combustion engine structure is proposed from two aspects of reducing mechanical resistance and energy loss. The new internal combustion engine is mainly composed of a crankshaftless piston and an energy converter. Among them, the crankshaft-free piston cancels the crankshaft connecting rod mechanism in the structure. The reciprocating linear motion of the piston solves the problem of side force and can effectively reduce the mechanical resistance. The energy converter is mainly composed of the cylinder valve and the shell. Through the rotation of the cylinder valve and the structure of the shell, the hydraulic oil is used as the medium to realize the energy storage and conversion, which reduces part of the energy loss and improves the combustion thermal efficiency. In addition, the new type of internal combustion engine can use flexible fuel, hydrogen engine provides a new direction for the new type of internal combustion engine fuel, combustion medium uses clean energy hydrogen or ammonia, in line with the national "two-carbon" policy, wide application prospects. The new structure of internal combustion engine proposed in this paper can provide a new idea for improving the thermal efficiency of internal combustion engine.

Key words: Crankshaftless; Internal combustion engine; Thermal efficiency; Energy converter; Clean energy