An investigation of the transonic pressure drag coefficient for axi-symmetric bodies
MetadataShow full item record
This thesis investigates the pressure drag coefficient in the transonic regime over an axi-symmetric body, with a set of unique contour surfaces developed in a previous thesis. The contour surfaces were obtained by an exact solution of the small perturbation transonic equation, using the guidelines and tools developed at NPS. In this work, Computational Fluid Dynamics (CFD) was not only used to compute the afterbody contour surface, but also to investigate a conical afterbody and complete bodies, which are composed of an arbitrary forebody (ellipsoid) and a variable afterbody (contour and conical). Euler as well as Navier-Stokes flow-solvers were applied to the geometries of interest, giving Mach-number contours for viscous and inviscid flow, pressure drag coefficient magnitude, and depicting shock wave location. On the basis of these results, it can be verified that our contour surface afterbodies will decrease by 15% the peak of the pressure drag coefficient (C sub d) versus Mach number curves in the transonic regime. These results can be used to design low pressure drag surfaces for such as missiles, projectiles and aircraft engine nacelles
Showing items related by title, author, creator and subject.
Fan, Yue Sang (Monterey, California. Naval Postgraduate School, 1995-03);Viscous drag in the transonic regime over an axi-symmetric body with a unique aft contour surface is investigated. The forebody is composed of an arbitrary ellipsoid. The unique aft contour surface has been obtained by an ...
Hurley, Andrew M. (Monterey California. Naval Postgraduate School, 2008-06);Operational experience indicates that steam escaping from carrier catapults has the potential to induce stall or surge in the compressors of jet aircraft during takeoff. As the carrier fleet ages and the Navy transitions ...
Salama, Aharon (Monterey, California. Naval Postgraduate School, 1992-03);The small perturbation, two-dimensional transonic equation is manipulated with a separation- of -variables approach to obtain two ordinary, nonlinear, differential equations. Numerical integration of these differential ...