Prediction of Flows about Forebodies at High-Angle-of-Attack Dynamic Conditions
Abstract
A Reynolds-average Navier Stokes (RaNS) code (OVERFLOW) developed for rotorcraft flow problems is used to predict the forces and moments of two forebody models at high angle-of-attack dynamic conditions, and to provide insight into flow characteristics in these conditions. This paper focuses on the steady-state flow problem. In the mid-1990s, rotary balance experiments were conducted on square and circular ogive forebodies at angles of attack of 60 and 90 degrees over a range of Reynolds numbers (based on the body diameter/width, D, and freestream velocity) from 0.08 x 10(exp 6) to 2.25 x 10 (exp 6). The wind tunnel experiments were conducted by NASA Langley and the Defence Evaluation and Research Agency (DERA) in Bedford and Farnborough, United Kingdom. The purpose of these experiments was to determine the effects of Reynolds number, angular velocity, and geometric shape on the aerodynamic characteristics of the forebodies. These tests were unique in so far that this was the first time that surface pressure distributions were measured under dynamic conditions in a pressurized wind tunnel. A second objective of these experiments was to provide a database for the development/validation of high angle-of-attack computational methods. This database forms the basis for this computational investigation. In the next section the forebody models as well as the experimental setup used to generate the database are discussed, followed by a brief discussion of the rotorcraft version of OVERFLOW and the computational grids on which the solutions were obtained. Computational results are presented for the circular and square ogives at steady rotary conditions and these results are compared against the experimental findings.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 2003
- Accession Number
- ADA419019
Entities
People
- C. M. Fremaux
- C. P. Van Dam
- S. Saephan
- T. Dalbello
Organizations
- University of California, Davis