In order to accurately predict the spray angle of pintle injector unit

the theoretical model of spray angle of liquid jet impinging on gas sheet was established based on momentum conservation. The deformation factor was obtained by experimental results. Moreover

the influence of structure parameters and operation parameters on spray angle was analyzed. The results showed that the local momentum ratio had the greatest influence on the spray angle

and other structure parameters and operation parameters further determined the spray angle by influencing the local momentum ratio. As the local momentum ratio increased

the deformation of the liquid jet decreased. The effective momentum ratio was less than the geometric momentum ratio due to liquid jet deformation. According to the experimental results

the value of the deformation factor was given in sections. When the local momentum ratio ranged from 0 to 3

the recommended value of the deformation factor was 0.61. When the local momentum ratio ranged from 3 to 4.5

the recommended value of the deformation factor was 0.70.When the local momentum ratio ranged from 4.5 to 7.2

the recommended value of the deformation factor was 0.75. The theoretical predicted value of the deformation factor was in good agreement with the experimental results. This model can provide a reference for the theoretical research and engineering design of gas-liquid pintle injector.