Modeling Study On Ultraviolet Radiation Characteristics Of Bow Shock

When hypersonic aircraft flying within the atmosphere, blunt head body will face a strong stream compression, the aircraft will head detached bow shock formed. In hypersonic flight conditions, due to the aircraft wall and the intense friction of the atmosphere, from the vicinity of the aircraft to its head appears around the high temperature, the main component of air is nitrogen and oxygen generating violent collision, and then level transition occurs generating a series of complex nonequilibrium chemical reactions, photochemical reaction, dissociation of diatomic molecules, ionization of atoms, molecules and so on.This paper focuses on computing the flow field of bow shock aircraft and NO(A) of bow shock UV radiation intensity calculation model was studied, the experimental data of the United States twice UV flight tests(BSUV1, BSUV2) and the simulation data for comparison, key elements are list as follows:(1) Research component bow shock in the flow fieldStudy on the abroad variety of high temperature air chemistry model applicability, relating to the Park5 components, 7 component chemical reactions model and Boyd’s 2007 rarefied gas reaction model. First, Adopt FASTRAN to calculate the flow field, especially in the flight altitude of 40 km height calculation of the flow field simulation results can be a good fit tothe references data; calculate the degree of matching of the flight altitude of 71 km best flow field. Then DSMC for more rarefied environment is calculated andanalyzed. And the results were compared with the references.(2) Study number density and spectral intensity of the radiation model N O(A) bow shock in Solution.Study the chemical reaction modelfor calculatingthe number of NO(A) in the flow field usingthe "quasi-steady-state model." In the process, the reverse chemical reaction rate being the key, apply the principle of detailed balance to settle it. Then the various components of the sensitivity of NO(A) were analyzed. Finally, the flow field in the NO(A) of spectral radiation intensity was calculated, andcompare with the United States twice UV flight tests(BSUV1, BSUV2) experimental data.