The simplified physical and mathematical models of the working process in valveless pulsejet based on the analysis of such engine cycle were proposed.The flow principle of combustor of charging process and the relationship of the mean velocity of discharge with thermodynamic parameters and combustor pressure were achieved

then the equations of the operation frequency and mean thrust were given.The results show that non-dimensional mean velocity of discharge increases with the increase of the compression ratio

and tendency is mitigated;the errors between the results of operation frequency and mean thrust models and experimental data are less than 10% and ±17%;in addition

the equation of thrust is suitable for valved pulsejet.The study shows that presented simplified analytical models are reasonable

and the accuracy is acceptable.The conclusions offer instruction for designing

experiment

predicting the performance and optimization method of valveless pulsejet.