Dominance of Radiated Aerodynamic Noise on Boundary-layer Transition in Supersonic-hypersonic Wind Tunnels

Dominance of Radiated Aerodynamic Noise on Boundary-layer Transition in Supersonic-hypersonic Wind Tunnels
Author: Samuel R. Pate
Publisher:
Total Pages: 418
Release: 1978
Genre: Aerodynamic noise
ISBN:

An experimental investigation was conducted to determine the effects of radiated aerodynamic-noise on boundary-layer transition in supersonic-hypersonic wind tunnels. It is conclusively shown that the aerodynamic noise (pressure fluctuations associated with sound waves), which radiate from the tunnel wall, turbulent boundary layer, will dominate the transition process on sharp flat places and sharp slender cones at zero incidence.

Experimental Aerodynamics

Experimental Aerodynamics
Author: Bruno Chanetz
Publisher: Springer Nature
Total Pages: 329
Release: 2020-01-03
Genre: Science
ISBN: 3030355624

This book presents experimental techniques in the field of aerodynamics, a discipline that is essential in numerous areas, such as the design of aerial and ground vehicles and engines, the production of energy, and understanding the wind resistance of buildings. Aerodynamics is not only concerned with improving the performance and comfort of vehicles, but also with reducing their environmental impact. The book provides updated information on the experimental and technical methods used by aerodynamicists, engineers and researchers. It describes the various types of wind tunnels – from subsonic to hypersonic – as well as the problems posed by their design and operation. The book also focuses on metrology, which has allowed us to gain a detailed understanding of the local properties of flows, and examines current developments toward creating a methodology combining experiments and numerical simulations: the computer-assisted wind tunnel. Lastly, it offers an overview of experimental aerodynamics based on a prospective vision of the discipline, and discusses potential futures challenges. The book can be used as a textbook for graduate courses in aerodynamics, typically offered to students of aerospace and mechanical engineering programs, and as a learning tool for professionals and engineers in the fields of aerodynamics, aeronautics and astronautics automobile.

Boundary Layer Transition at Supersonic Speeds

Boundary Layer Transition at Supersonic Speeds
Author: E. R. Van Driest
Publisher:
Total Pages: 108
Release: 1961
Genre: Aerodynamics, Supersonic
ISBN:

Experiments carried out in the 12-inch supersonic wind tunnel to investigate the effect of three dimensional roughness elements (spheres) on boundary-layer transition on a 10-degree (apex angle) cone without heat transfer are described. The local Mach number for these tests was 2.71. The data show clearly that the minimum (effective) size of trip required to bring transition to its lowest Reynolds number varies power of the distance from the apex of the cone to the trip. Use of available data at other Mach numbers indicates that the Mach number influence for effective tripping is taken into account by a simple expression. Some remarks concerning the roughness variation for transition on a blunt body are made. Finally, a general criterion is introduced which gives insight to the transition phenomenon and anticipates effects of external and internal disturbances, Mach number transfer.

Effects of Radiated Aerodynamic Noise on Model Boundary-layer Transition in Supersonic and Hypersonic Wind Tunnels

Effects of Radiated Aerodynamic Noise on Model Boundary-layer Transition in Supersonic and Hypersonic Wind Tunnels
Author: S. R. Pate
Publisher:
Total Pages: 94
Release: 1968
Genre:
ISBN:

Boundary-layer transition and aerodynamic noise measurements were made on sharp leading-edge two-dimensional models in supersonic wind tunnels (1 ft to 16 ft). These data showed, conclusively, a significant and continuous increase in transition Reynolds number and a significant decrease in radiated aerodynamic noise (generated by the tunnel wall turbulent boundary layer) with increasing tunnel size. Results obtained in the AEDC-VKF Tunnel A from a shroud configuration placed concentrically around a hollow cylinder transition model and a flat plate microphone model further demonstrated the strong adverse effects that radiated aerodynamic noise will have on transition. A correlation of transition Reynolds numbers based on transition data from nine wind tunnels (3

Fluid Dynamics Research on Supersonic Aircraft

Fluid Dynamics Research on Supersonic Aircraft
Author: North Atlantic Treaty Organization. Research and Technology Organization
Publisher:
Total Pages: 342
Release: 1998
Genre: Technology & Engineering
ISBN:

Contains the lecture notes prepared for a Special Course on Fluid Dynamics Research on Supersonic Aircraft organized by the RTO Applied Vehicle Technology Panel (AVT). The Course was held at the von Kármán Institute for Fluid Dynamics (VKI) Institute, Rhode-Saint-Genèse, Belgium 25-29 May 1998. The following topics were covered: History & Economics of Supersonic Transports, Supersonic Aerodynamics, Sonic Boom Theory and Minimization, Multi-Point Design Challenges, Vortex Plume Interactions, Propulsion System Design. Presentations on the major world wide supersonic transport programs were also included. The material assembled in this publication was prepared under the combined sponsorship of the RTO Applied Vehicle Technology Panel, the Consultant and Exchange Program of RTO, and the von Kármán Institute (VKI) for Fluid Dynamics.