A Typical Test
Introduction
In this section, we run through a typical test in the Transonic Wind Tunnel (TWT) from model preparation all the way through to data acquisition and processing. Each test stage has links to animations which show the process in action. Please note that for slower connection speeds, these animations could take a few minutes to load.
Model Preparation
A typical tests starts with the model being prepared in one of our secure model bays. The model is built up in stages starting with the support sting and balance.
To see animations of the model being built, follow the links below:
Model Installation
Once the model has been assembled, it is installed on a mobile cart before the cart is wheeled into the TWT test section.
To see animations of the model being installed in the test section, follow the links below:
- Model Installation on Mobile Cart
- TWT Moveable Test Section Opening
- Model moving from Model Bays into TWT Test Section
- Model Installation in TWT Test Section
Model Movement System
Once the model has been installed in the TWT test section and all the checks have been completed, the test begins.
An automated model movement system changes the attitude of the model during the test. Each movement sequence is called a “polar”.
There are two main types of polar. An “alpha” sweep is where the model is pitched relative to the airflow and a “beta” sweep is where the model is yawed relative to the airflow. The beta sweep is usually achieved with a combination of model pitch and roll.
To see animations of model movement polars, follow the links below:
Data Acquisition and Processing
During the test, data from the model is recorded, processed and displayed live on a dedicated set of screens.
To see an animation of some live data being recorded, follow the link below:
Video and Photographic Monitoring
As well as data, images and video of the model can be recorded and displayed live. An oil flow is a flow visualisation technique used to obtain an overview of the airflow over the model surface. A sequence of high quality photographs are taken for a series different model attitudes.
To see an animation of an oil-flow sequence where a shockwave is developing on a wing, follow the link below:
