The benchmark active controls technology and wind tunnel test program at NASA Langley Research Center was started with the objective to investigate the nonlinear, unsteady aerodynamics and active flutter suppression of wings in transonic flow. The paper will present the flutter suppression control law design process, numerical nonlinear simulation and wind tunnel test results for the NACA 0012 ...

A small transonic wind tunnel was designed, constructed and calibrated in order to provide a tool for the study and demonstration of transonic flow phenomena. The wind tunnel makes use of flow properties following the propagation of a shock wave along a tube in order to create the transonic flow. This is in contrast to conventional transonic facilities which are supplied from a reservoir or com...

High speed wind tunnels are widely used in the study of fluid flow behavior around various objects. The air flow in the starting step of supersonic wind tunnels is transient including strong shock waves caused by the interaction of the tunnel main stream and the boundary layer at walls. To arrive in running step, the tunnel must be designed so as these waves leave immediately the test section. ...

The benchmark active controls technology and wind tunnel test program at NASA Langley Research Center was started with the objective to investigate the nonlinear, unsteady aerodynamics and active flutter suppression of wings in transonic flow. The paper will present the flutter suppression control law design process, numerical nonlinear simulation and wind tunnel test results for the NACA 0012 ...

The history of Laminar Flow Control (LFC) from the 1930s through the 1990s is reviewed and the current status of the technology is assessed. Early studies related to the natural laminar boundary-layer flow physics, manufacturing tolerances for laminar flow, and insect-contamination avoidance are discussed. Although most of this publication is about slot-, porous-, and perforated-suction LFC con...

This analysis is performed to study the momentum, heat and mass transfer characteristics of MHD mixed convective flow past inclined porous plate in porous medium, including the effect of fluid suction. The fluid is assumed to be steady, incompressible and dense. Similarity solution is used to transform the problem under consideration into coupled nonlinear boundary layer equations which are the...

The objective of obtaining a spatially standardized steady stream of air across and along the test section of a wind tunnel has been considered by several researchers. When a wind tunnel is manufactured or montage or move to another position, the study about variation of pressure, Mach number, density and temperature distribution, the variation of pitch and yaw components of flow angularity, bo...

in this study, aerodynamic characteristics of a circular cylinder in an axial flow have been investigated numerically and experimentally. the model has been considered as a cylinder with truncated nose and fineness ratio of 3 (length to diameter ratio of 3). the investigation involves a series of wind tunnel measurements, flow visualization, and numerical simulation. we used different mach numb...

The NASA Common Research Model (CRM) was developed as an open-source contemporary transonic supercritical wing for various studies in aerodynamics (Vassberg et al. (2008)). Extensive detailed aerodynamic performance data have been generated since 2008, and collection of such data is still under way. These data serve as a good basis for CFD studies generally and, in particular, for the research ...