In order to solve the problem of combustion cycle variation in two-stroke aviation kerosene piston engines under idle conditions, experiments were conducted to investigate the influence of intake air temperature on combustion cycle variation and output work. The coefficient of variation of the indicated mean effective pressure was used to characterize combustion cycle variation. The results showed that there is a negative correlation between the engine combustion work and the combustion cycle variation. In the lower range, increasing the intake air temperature has a greater effect on reducing the combustion cycle variation, while in the higher range, the combustion cycle variation has a greater impact on the output work. At the same time, the influence of intake air temperature on the fuel evaporation rate is related to engine speed, and this relationship weakens as the engine speed increases. In the range of 0~40 °C, the higher the intake air temperature, the larger the stable combustion range.

To enhance the performance of aviation piston engine starters in high-altitude environments, this study investigated their transient starting characteristics under low-temperature and low-pressure conditions using a high-altitude simulation chamber. Experiments were conducted across ambient temperatures from −60 to 15 °C and pressures from 35 to 95 kPa. The results show that the ambient temperature significantly impacts the transient characteristics of the motor, particularly at the initiation stage, whereas pressure has a weaker effect. For every 5 °C drop in temperature, the peak starting current increases by 1.95 A. From 15 to −60 °C, the maximum difference in the starting current pulse width is 11.64 ms. Furthermore, as the ambient temperature decreases, the average current after the motor stabilizes increases, and the average speed decreases.

Initial temperature has a promoting effect on laminar burning velocity, while initial pressure and dilution rate have an inhibitory effect on laminar burning velocity. Equal laminar burning velocities can be obtained by initial condition coupling with different temperatures, pressures and dilution rates. This paper analysed the equivalent distribution pattern of laminar burning velocity and the variation pattern of an equal weight curve using the coupling effect of the initial pressure (0.1–0.3 MPa), initial temperature (323–423 K) and dilution rate (0–16%). The results show that, as the initial temperature increases, the initial pressure decreases and the dilution rate decreases, the rate of change in laminar burning velocity increases. The equivalent effect of initial condition coupling can obtain equal laminar burning velocity with an dilution rate increase (or decrease) of 2% and an initial temperature increase (or decrease) of 29 K. Moreover, the increase in equivalence ratio leads to the rate of change in laminar burning velocity first increasing and then decreasing, while the increases in dilution rate and initial pressure make the rate of change in laminar burning velocity gradually decrease and the increase in initial temperature makes the rate of change in laminar burning velocity gradually increase. The area of the region, where the initial temperature influence weight is larger, gradually decreases as the dilution rate increases, and the rate of decrease gradually decreases.