NUMERICAL INVESTIGATION OF INFLUENCE OF NOSE PART SHAPE OF A HIGH-SPEED VEHICLE ON AERODYNAMIC CHARACTERISTICS
DOI:
https://doi.org/10.32782/mathematical-modelling/2024-7-2-1Keywords:
high-speed vehicle, aerodynamics, Navier-Stokes equation, control volume method, aerodynamic coefficientsAbstract
Three-dimensional unsteady Reynolds-averaged Navier-Stokes equations are used to study the influence of the nose shape on the aerodynamic characteristics of a high-speed vehicle. The SST turbulence model was used to simulate turbulence. The software and methodology for numerical modelling and determination of the main parameters of the unsteady flow of a high-speed vehicle was developed. The numerical solution of the system of initial equations is performed by the method of control volumes. The block-matrix system of linear algebraic equations of the implicit scheme was solved by the Generalized minimal residual method (GMRES) with an incomplete LU decomposition (ILU(k)) of the total matrix of the system as a preconditioner. The results of three-dimensional flow visualisation are presented. The distribution of the gas-dynamic characteristics of the flow around the body of a high-speed vehicle near the road structure is determined. The distribution of the gas-dynamic characteristics of the high-speed vehicle body flow near the road structure is determined. The influence of the length, width, and height of the nose section on the aerodynamic characteristics of a high-speed vehicle is analysed and determined. An increase in length and height reduces drag, and an increase in the width of the nose of the high-speed vehicle leads to an increase in the coefficient of drag. Regardless of the geometric parameters of the nose section, the body of the high-speed vehicle is subject to a negative lift force that presses the body against the road structure and a positive pitching moment. An increase in the length and width of the nose section, as well as the height of its installation above the track structure, leads to a decrease in the modulus of the downward force and the pitching moment. The developed methodology and calculation results can be applied to the study of coupled problems of dynamics and aerodynamics, optimisation of aerodynamic shape, as well as to the selection of design parameters of a high-speed vehicle on superconducting magnets, suspension system and track structure.
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