On Results' Accuracy at Two-Dimensional Transonic Wind Tunnel Testing

11-Foot Transonic Wind Tunnel

This paper describes a modeling method and a new optimal control approach to investigate a Mach number control problem for the NASA Ames 11-Foot Transonic Wind Tunnel. The flow in the wind tunnel is modeled by the 1-D unsteady Euler equations whose boundary conditions prescribe a controlling action by a compressor. The boundary control inputs to the compressor are in turn controlled by a drive ...

A Shock Tube Driven Transonic Wind Tunnel

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...

Transonic Flutter Suppression Control Law Design, Analysis and Wind Tunnel Results

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 ...

Some Experiments with Static Tubes at Transonic Speeds in a Slotted-Wall Wind Tunnel

Experimental wind tunnel testing of linear individual pitch control for two-bladed wind turbines

In this paper Linear Individual Pitch Control (LIPC) is applied to an experimental small-scale two-bladed wind turbine. LIPC is a recently introduced Individual Pitch Control (IPC) strategy specifically intended for two-bladed wind turbines. The LIPC approach is based on a linear coordinate transformation, with the special property that only two control loops are required to potentially reduce ...