Aerodynamic Characteristics Analysis Of Б M-21Rockets Retrofit

In this paper, taking БM-21rockets modification as the research object, it was proceeded analysis of aerodynamic characteristics. Aerodynamic characteristics analysis method with the theoretical calculation method of air, wind tunnel experiment and numerical simulation method. But as a result of theoretical calculation are not able to fully consider all factors play arrow flight, so get the aerodynamic parameters deviation is larger, usually only used as the initial stage of theory reference value. Blowing with wind tunnel experiment is now the most commonly used method in engineering, but cost is too high and the cycle is long, generally only used in the final phase weapons research. And the numerical simulation method can simulate the projectile flight is the most real situation, and particularly low cost, by using this method is very suitable in r&d phase. Numerical simulation has become an important means and approaches to the study of the projectile.In this paper, БM-21rockets is used to numerically simulate for the flight status of different Angle of attack and Mach number, At the same time also the part of the flight the situation of the rocket-propelled grenades carried out the wind tunnel hair experimental, in order to compare the results of numerical simulation. The drag coefficient obtained by wind tunnel experiments and numerical simulation were compared, the results found in subsonic, in subsonic, numerical simulation results relative to experimental data is slants big some, The deviation is about10%; transonic and supersonic, numerical simulation results with experimental data close to, The deviation is about4%, and broadly in line the general rules of the drag coefficient. Thus it verify the accuracy of the results of numerical simulation, and to ensure that rockets fly in the other case directly adopts numerical simulation to simulate the accuracy of its results. Finally, the two play type pneumatic characteristics were analyzed. БM-21modified bomb flow field contours than БM-21tail bomb contour distribution symmetrical; The modified bomb in the attack angle of0degrees drag coefficient is smaller than volume tail bomb; Retrofit rocket stable reserve amount is large compared to БM-21Volume tail rockets. These fully illustrated БM-21modified bomb stabilizing device better than БM-21tail shells, and БM-21modified bomb stable flight line better.