Study on similarity law of load reduction technology of launcher air curtain

Objectives The technology of reducing load by air curtain at the muzzle of the launch tube is a technology that sprays air at the muzzle to reduce load when launching an underwater vehicle. In order to better simulate the process of a full-scale vehicle exiting the tube in a complex environment through a scaled-down test, it is necessary to carry out research on the similarity law of the engineering scaled-down test of the technology of reducing load by air curtain at the muzzle of the launch tube.

Methods Based on the relevant influencing parameters of underwater launch, the π theorem is applied to derive the similarity criteria of the underwater launch process. At the same time, the similarity criteria analysis of the pressure equalization and exhaust process of the vehicle and the air curtain injection process is carried out to obtain the similarity criteria of the decompression model. Aiming at the problem that the bubble pressure and range in the air curtain injection process under the similarity criteria of the decompression model are not synchronously similar, the similarity criteria of the isobaric model are further established, and comparative analysis tests between the decompression model and the isobaric model are carried out.

Results Based on the relevant influencing parameters of underwater launch, the π theorem is applied to derive the similarity criteria of the underwater launch process. At the same time, the similarity criteria analysis of the pressure equalization and exhaust process of the vehicle and the air curtain injection process is carried out to obtain the similarity criteria of the decompression model. Aiming at the problem that the bubble pressure and range in the air curtain injection process under the similarity criteria of the decompression model are not synchronously similar, the similarity criteria of the isobaric model are further established, and comparative analysis tests between the decompression model and the isobaric model are carried out.

Conclusions The research results can provide a reference for the simulation of complex underwater launch environments.