Open AccessAERODYNAMICS OF JETS INTERACTING WITH A FLAT SURFACE
Author(s) -
И. А. Прибытков,
С. И. Кондрашенко
Publication year - 2019
Publication title -
izvestiâ vysših učebnyh zavedenij. černaâ metallurgiâ
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.3
H-Index - 7
eISSN - 2410-2091
pISSN - 0368-0797
DOI - 10.17073/0368-0797-2019-4-263-269
Subject(s) - aerodynamics , nozzle , jet (fluid) , mechanics , turbulence , physics , surface (topology) , radius , heat transfer , stagnation point , classical mechanics , thermodynamics , geometry , mathematics , computer science , computer security
In this paper, the development features of a single free jet of hightemperature nitrogen interacting with a at surface were studied. Calculation of the heat exchange process during heating by the attacking jets is very difficult to implement analytically due to complexity of the gas-dynamic processes occurring both in a single jet and in a system of jets interacting with the metal. The computational difficulties are aggravated by the fact that when interacting with the surface the jet as such disappears. The at (fan) ow interacts with the surface: form, aerodynamic properties and thermal state of the ow strongly dier from those of the original jet. The studies were conducted on the basis of numerical simulation in the FloEFD software and computing complex for multiphysical simulation based on solution of the equations of gas dynamics and heat transfer. The solved system of equations consisted of Navier-Stokes equations, equations of energy and continuity and was supplemented by k – ε turbulence model. A three-dimensional model was developed for simulation, the necessary properties, initial and boundary conditions were specified. In the study of aerodynamics of a single high-temperature jet interacting with the surface, the main defining values were: nitrogen ow rate from the nozzle U 0 , nitrogen temperature T , internal diameter of the nozzle d 0 , distance from the nozzle section to the surface h , distance from the critical point (point of intersection of the jet axis with the surface) along the ow radius r . Data on the gas velocity decrease as the jet develops due to the loss of initial energy to engage the motionless surrounding gas in motion, is presented. The studies have shown that increase in the initial velocity of gas outow brings the area of higher velocities closer to the surface both in the jet itself and in the fan jet. This factor contributes to heat transfer intensification. In addition, high speeds increase the total thickness of the fan ow and reduce the thickness of hydrodynamic boundary layer, which increases with distance from the critical point.