Numerical simulation of thermophysical processes in the bubble as an element of a masking curtain

The movement of a bubble in an air stream with the consideration of the heat exchange process between the air, the bubble shell and the heated air inside the bubble was numerically investigated. Numerical modeling was carried out in the Ansys Fluent software product. It was assumed that the injection of the bubble takes place in the air flow, which has a speed of 3 m/s, and the air temperature is 293 K. The calculation was carried out for the diameters of the bubbles, which were equal to 3 mm and 5 mm. The thickness of the bubble shell was equal to 1 μm. It was assumed that at the time of injection of the bubble into the air flow, the initial temperature of the heated air, which is filled with the bubble, exceeds the temperature of the surrounding air in the first variant by 10 K and in the second variant by 30 K. The velocity field of the air flow that occurs inside the bubble during its external flow with a speed of 3 m/s and when the external air is stationary. The bubble surface temperature and air velocity vector field are calculated. Based on the analysis of the simulation results, it was determined that achieving the volatility of the bubble by heating the gas is not expedient due to the short air cooling time, which in the calculated versions did not exceed 250 ms. Therefore, the most effective method for achieving bubble volatility is determined in this paper. Based on the above, we come to the general conclusion that the filling should be with a gas of the density that is less than the density of air under the same thermodynamic conditions. These processes should form the basis of a mechanism that will ensure thermal reconnaissance protection of armoured weapons. This function is most effective when the enemy uses night vision devices. This area should take constant development steps to counteract the enemy's reconnaissance tasks. The material part of the study (gas and liquid) should be studied in interaction and subject to experimental investigation. These actions are aimed at achieving maximum effect.