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Numerical research on the muzzle multiphase flow field produced by gas curtain launch
Jinghui Zhang1, Guangtao Liu2, Wenji Han2
1China Ship Scientific Research Center, National Key Laboratory Of Hydrodynamics, Wuxi, 214000, China. 542651213@qq.com.
Scientific Reports
|November 26, 2024
Summary
Underwater gun firing uses a gas curtain to improve efficiency. This study models the complex muzzle flow, revealing shock wave dynamics and pressure changes crucial for projectile accuracy.
Area of Science:
- Fluid dynamics
- Underwater ballistics
- Multiphase flow
Background:
- Gas curtain launch is an innovative underwater firing technique.
- The gas curtain interacts with post-projectile gas and water, creating a complex muzzle flow field.
- This flow field significantly affects projectile accuracy.
Purpose of the Study:
- To investigate the evolution of the multiphase flow field at the muzzle during gas curtain launch.
- To analyze the distribution of shock waves, temperature, and pressure.
- To understand the impact on projectile accuracy.
Main Methods:
- Development of a three-dimensional numerical model.
- Simulation of the gas curtain's interaction with post-projectile gas and water.
- Analysis of shock wave formation, Mach disk evolution, temperature, and pressure distribution.
Main Results:
- A bottle-shaped shock wave is formed by the gas curtain's expansion and compression.
- The Mach disk diameter decreases exponentially over time.
- High temperatures and pressures are observed downstream of the Mach disk, influenced by projectile interaction.
Conclusions:
- The gas curtain launch creates a complex flow field impacting underwater ballistics.
- Understanding shock wave dynamics is key to optimizing projectile accuracy.
- Numerical modeling provides insights into the multiphase flow phenomena.
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