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Vira, N. R.

Publications and source records attributed to Vira, N. R..

3 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1982

Supersonic wing-body center of pressure with finite afterbodies

Closed-form formulas for the effects of finite afterbodies on the longitudinal center of pressure location in the presence of a wing at supersonic speeds are presented, along with solutions for the case of negative afterbodies. A double integral is developed for the case of subsonic and supersonic leading edges and no afterbody and full afterbody. Attention is also given to the full/infinite body case, noting that a proportional variation of the pitching moment with the lift is found.

Vira, N. R.↗
NASA NTRS1982

Closed-form solutions of supersonic wing-body interference

Closed-form formulas are presented for the interference factors of a body in the presence of a wing at supersonic speeds, when a finite afterbody is introduced. In addition, formulas are obtained for those cases in which the base of the body is forward of the trailing edge of the exposed root chord. These formulas are shown to be valid, subject to the restrictions inherent in the formulation given by Pitts, Nielsen and Kaattari (1959).

Vira, N. R.↗
NASA NTRS1979

An Improved Theoretical Aerodynamic Derivatives Computer Program for Sounding Rockets

The paper outlines a Theoretical Aerodynamic Derivatives (TAD) computer program for computing the aerodynamics of sounding rockets. TAD outputs include normal force, pitching moment and rolling moment coefficient derivatives as well as center-of-pressure locations as a function of the flight Mach number. TAD is applicable to slender finned axisymmetric vehicles at small angles of attack in subsonic and supersonic flows. TAD improvement efforts include extending Mach number regions of applicability, improving accuracy, and replacement of some numerical integration algorithms with closed-form integrations. Key equations used in TAD are summarized and typical TAD outputs are illustrated for a second-stage Tomahawk configuration.

Barrowman, J. S.↗