Accession Number : ADA255954


Title :   Transonic Flow Calculations for a Cavity With and Without a Store


Descriptive Note : Final rept. Oct 1988-Jan 1992


Corporate Author : ARNOLD ENGINEERING DEVELOPMENT CENTER ARNOLD AFB TN


Personal Author(s) : Suhs, N E


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a255954.pdf


Report Date : Sep 1992


Pagination or Media Count : 110


Abstract : A computational fluid dynamics capability has been developed to support weapons bay (cavity) and internal store separation testing. Specifically, a computational capability that can be used to improve the ability to predict store trajectories and strut or sting interference was targeted by this effort. The chimera embedded grid scheme, a domain decomposition technique, was used to divide the cavity, store, and support hardware into simpler overlapping regions for which grids were more easily generated. The flow field was solved using an implicit Navier-Stokes code based on the Pulliam-Steger algorithm with thin-layer approximations to the viscous terms. Unsteady flow calculations were made for an empty cavity at Mach numbers of 0.60, 0.95, and 1. 20 for a cavity length-to-height ratio of 4.5. Computations were also made for an ogive-cylinder-ogive store supported by a sting and positioned both in a free-stream flow and in the plane of the cavity opening at Mach numbers of 0.60, 0.95, and 1.20. Additional flow-field computations were made for the store supported by the sting at other positions within and outside the cavity at a Mach number of 1.20. Comparisons of the computations with experimental data were made for the time-averaged and fluctuating static pressures along the walls of the cavity for all of the above calculations. Comparisons were also made for the computed and measured time-averaged static pressures located axially along two opposing sides of the store. The evaluation of sting interference was achieved by removing the sting grid, calculating the flow field for this new configuration, and assessing differences between the store pressures and loads with and without the sting.


Descriptors :   *CAVITIES , *EXTERNAL STORE SEPARATION , ALGORITHMS , BAYS , COMPARISON , COMPUTATIONS , CONFIGURATIONS , DECOMPOSITION , DYNAMICS , EXPERIMENTAL DATA , FLOW , FLOW FIELDS , FLUID DYNAMICS , FLUIDS , FREE STREAM , GRIDS , HEIGHT , INTERFERENCE , INTERNAL , LAYERS , LENGTH , MACH NUMBER , NUMBERS , OGIVES , OPENINGS , PRESSURE , RATIOS , REGIONS , SEPARATION , STATIC PRESSURE , STATICS , STORES , STREAMS , STRUTS , TIME , TRAJECTORIES , UNSTEADY FLOW , WALLS , WEAPONS


Subject Categories : Fluid Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE