Author: Marie H. TuttlePublisher:
ISBN:
Category : Wind tunnel walls
Languages : en
Pages : 60
Book Description
Further Investigations of Adaptive-Wall Wind Tunnels
Author: J. C Erickson (Jr)Publisher:
ISBN:
Category :
Languages : en
Pages : 72
Book Description
The objective of this investigation was to continue the assessment of the Calspan perforated-wall, segmented-plenum adaptive-wall wind tunnel for flows in which the tunnel walls are supercritical. An important aspect of the investigation was the development of a static-pipe measuring technique for determining the normal velocity distributions. This technique was developed to overcome the limitations on the number of flow-angle probe measurements that could be made in the Calspan tunnel. The flow about a static pipe in the presence of model/wall-induced disturbances was analyzed within the framework of slender-body theory to give the relationship between differential pressure measurements across the pipe and the steam-wise derivative of the normal velocity at the pipe centerline.
Adaptive-wall Wind-tunnel Investigations
Author: J. C. EricksonInvestigation of Adaptive Wall Wind Tunnels with Two Measured Interfaces
Author: C. F. LoAdaptive Wall Wind Tunnels
Author: Marie H. TuttlePublisher:
ISBN:
Category : Wind tunnel walls
Languages : en
Pages : 44
Book Description
Research on Adaptive Wall Wind Tunnels
Author: Robert J. VidalPublisher:
ISBN:
Category : Aerodynamics, Transonic
Languages : en
Pages : 70
Book Description
The objective of this research was to investigate the utility of the Calspan self-correcting wind tunnel for minimizing or eliminating wall interference effects in two-dimensional transonic flows when shock waves from the test model extend to the tunnel walls. This report summarizes the experimental research performed with two-dimensional airfoils in the Calspan self-correcting wind tunnel and the theoretical research accomplished in support of the experiments. The experiments were performed with airfoil models having 4% and 6% solid blockage. The initial experiments with the 6%-blockage model were devoted to determining a practical mode of operation when shock waves from the model extend to the wall. The most practical model is to use wall control to obtain the desired distribution of longitudinal velocity components for subcritical walls. The Mach number is then increased and the wall control is readjusted, sequentially, until the desired test condition is achieved. At the high Mach numbers of interest, however, the available wall control was limited locally, and tunnel system changes were required. A method is reported for analyzing self-correcting wind tunnels with porous walls.
Adaptive Wall Wind Tunnels
Author: Marie H. TuttlePublisher:
ISBN:
Category : Wind tunnel walls
Languages : en
Pages : 60
Book Description
Adaptive Wall Wind Tunnels: A Selected, Annotated Bibliography
Author: Marie H. TuttleAdaptive Wall Wind Tunnel Investigation of a Circulation Controlled Circular Cylinder
Author: Roland Gunther BerndtPublisher:
ISBN:
Category :
Languages : en
Pages : 266
Book Description
Experimental Investigation of the Effect of Wall Adaptation on Flow Over a Cylinder in a Modernized Adaptive-wall Wind Tunnel
Author: Michael Joseph BishopPublisher:
ISBN:
Category :
Languages : en
Pages : 140
Book Description
A renovation of an adaptive-wall wind tunnel was completed to improve flow quality, automate data acquisition, integrate a three-axis traversing mechanism, and regain functionality of an adaptive-wall test section. Redesign of the settling chamber significantly improved flow quality, with the resulting turbulence intensity of 0.3% and flow uniformity of ±0.6% matching characteristics of research-grade wind tunnels. The functionality of the adaptive-wall test section was tested by analyzing the effect of wall adaptation on flow development over a circular cylinder. Experiments were carried out for a Reynolds number (Red) of 57,000 for three blockage ratios: 5%, 8%, and 17%. Measurements were made in three wall configurations: geometrically straight walls (GSW), aerodynamically straight walls (ASW), and streamlined walls (SLW). Solid blockage effects were clearly evident in cylinder surface pressure distributions for the GSW and ASW configurations, manifested by an increased peak suction and base suction. Upon streamlining the walls, pressure distributions for each blockage ratio matched distributions expected for low blockage ratios. Wake blockage limited wake growth in the GSW configuration at 7.75 and 15 diameters downstream of the cylinder for blockages of 17% and 8%, respectively. This adverse effect was rectified by streamlining the walls with the resulting wake width development matching that expected for low blockage ratios. Wake vortex shedding frequency and shear layer instability frequency increased in the GSW and ASW configurations with increasing blockage ratio. Invariance of the near wake width with wall configuration suggests that frequency increase is caused by the increased velocity due to solid blockage effects. For all the blockage ratios investigated, the increased wake vortex shedding frequency observed in the ASW and GSW configurations was corrected in the SLW configuration, with the resulting Strouhal numbers of about 0.19, matching that expected for low blockage ratios at the investigated Red.
Experimental Investigation of a 2D-circulation Controlled Cylinder in an Adaptive Wall Wind Tunnel
Author: Fabrizio Adalberto Maria DionisioPublisher:
ISBN:
Category : Wind tunnels
Languages : en
Pages : 320
Book Description