A three dimensional numerical wind tunnel based on the Navier-Stokes equations for viscous, incompressible fluid and LES method is established. Incoming wind field is generated based on the AIJ guidelines (2004). The numerical wind tunnel is validated against experimental results. A low-rise building with green roof is tested in the numerical wind tunnel. The results show that the green roof re...

The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. Use of probabilistic techniques has been demonstrated to learn air data parameters from surface pressure measurements. Integration of numerical models with wind tunnel data and sequential experiment design of wind tunnel runs has been demonstrated in the calibration of a flush ...

This paper describes the development of transfer function models for the trailing edge and upperand lower-spoiler actuators of the Benchmark Active Control Technology (BACT) wind-tunnel model for application to control system analysis and design. A simple nonlinear least squares parameter estimation approach is applied to determine transfer function parameters from frequency response data. Unco...

Boundary-layer wind tunnel provides a unique platform to reproduce urban, suburban and rural atmospheric boundary layer (ABL) by using roughness devices such as vortex generators, floor roughness, barrier walls, and slots in the extended test-section floor in the contraction cone. Each passive device impacts wind properties in a certain way. In this study, influence of various passive devices o...

During the past decade, the Navy has considerably improved its capabilities in aircraft/weapon integration. In 1989 it took more than 400 hours of wind tunnel testing, which cost 1,5000,000, and 20 flights to clear the JSOW from the F-18 to Mach 0.95. This year the MK-83 JDAM was cleared after only 60 hours of wind tunnel testing and five flights to the full F-18 aircraft envelope of Mach 1.3. ...

Tendency to build more slender and more flexible tall buildings have made these structures susceptible to action of wind. Therefore, wind force is one of the prime considerations in design of tall buildings. The prediction of wind-induced pressure coefficients on the surface of the buildings is of considerable practical importance. Wind tunnel testing is one of the main methods for wind load de...

The objective of this paper is to compare the current state-of-the-art of the following three optical techniques under study by NASA for measuring model deformation in wind tunnels: (1) video photogrammetry, (2) projection moiré interferometry, and (3) the commercially available Optotrak system. An objective comparison of these three techniques should enable the selection of the best technique ...

This article presents analytical and computational analysis of the influence of the wind tunnel walls on transonic airfoil tests. The goal is to quantify the effects of the wind tunnel walls and characterize the key parameters affecting the flow field in order to construct a numerical model to realize experimental data corrections. Firstly, the experimental data are compared with well-documente...

This work presents estimates of time histories of pressure coefficients at several taps on the roof of a 1/200 model of a 200 x 100 x 20 ft low-rise building with a 1/24 slope gable roof building. The estimates were obtained using a large eddy simulation (LES). The first and second moments as well as peaks for the time histories are compared with those obtained in boundary layer wind-tunnel mea...