Аннотация:

The article discusses the issues of assessing the thermal regime of a cable-mast located near the cryogenic tank of a launch vehicle, when exposed to wind. The results of numerical simulation of the transfer of cold air masses are compared with the results of calculations by engineering methods. Validation was carried out to determine the degree of correspondence of the mathematical model to the real object. The temperature values were obtained at the design points closest to the structural elements.

Ключевые слова:

thermal loads, cable-mast, free convection, cooling, numerical calculation

Основной текст труда

Cryogenic temperatures during the operation of the launch equipment can negatively affect the properties of the metal, making it more brittle and brittle to mechanical stress. Therefore, the goal is to determine the parameters of the air environment (air temperature) in order to observe the cable-mast at a distance of 150 mm from the tank shell and beyond, taking into account the convective cold air currents and the impact of wind with wide values of speed. The movement of cooled air in the boundary perception also cooling the structural elements of the cable-mast.

To research the thermal loads on the cable-mast, a 3D model was developed that simulates parts of a space rocket and a cable-mast with a certain degree of geometry simplification. To solve the problem, a grid model of the computational domain was built in the program Ansys ICEM [1].

The article also considers engineering methods for determining the temperature in the boundary layer in the free convection mode. In case when stable cold vertical wall circled by warm gas, its convective motion occurs. It occurs in a volume called a freely convective boundary layer, and is caused by the difference in air densities in the boundary layer and outside it [2]. A series of numerical calculations were carried out under the condition of free and forced convection, as well as a comparison of the results obtained with the results of calculations using engineering methods. Numerical modeling was done in program Ansys Fluent [3].

For proof the adequacy of the chosen numerical (mathematical) model, the simulation results were compared with the temperature measurement data obtained at the launch complex near the fueled oxidizer tank of the launch vehicle Souz-2. Measuring were carried out at a distance of 650 km from high point the power frame of oxidizer tank. Data analysis showed that results obtained in these cases were similar to each other.

Also in article additional examples of validation with experimental data when flowing around an increased flow of a cylinder with the formation of a vortex structure [4]. Experiments include visualization of the flow around a cylinder and measurement of the dynamics of instantaneous vector fields of the flow velocity in its wake. Presented the results of the research of the flow structure in the wake of a transversely streamlined cylinder located near the wall of a rectangular canal. With the help of numerical simulation, a qualitative agreement was obtained for the pattern of movement of turbulent structures obtained in an experimental setup.

Литература

- Yanyshev D.S., Bykov L.V., Molchanov A.M. Setochnye modeli dlya resheniya inzhenernykh teplofizicheskikh zadach v srede ANSYS. Moscow, URSS Publ., 2018. (In Russ.).
- Napalkov G.N. Teplo-massoperenos v usloviyakh obrazovaniya ineya. Moscow, Mashinostroenie, 1983. (In Russ.).
- Ansys Fluent Fluid Simulation Software. Available at: https://www.ansys.com/products/fluids/ansys-fluent (accessed August 10, 2022).
- Okhotnikov D.I., Mazo A.B., Molochnikov V.M., Malyukov A.V., Goltsman A.E., Saushin I.I. Viscous near-wall flow in a wake of circular cylinder at moderate Reynolds numbers. Thermophysics and Aeromechanics, 2017, vol. 24, no. 6, pp. 897–907. (In Russ.).