An advanced test rig that will be the starting point for a future series of wind tunnel models representing various classes of aircraft equipped with some forms of advanced propellers (counter or single rotating, tractors or pushers) will be designed. Engine simulators (turbine power simulators) will also be developed to simulate various types of advanced propeller engines.
An advanced test rig that will be the basic hardware of a future series of wind tunnel models representing various classes of aircraft equipped with some forms of advanced propellers will be built. This test rig will basically consist of a load bearing skeleton structure containing the model balance, a set of 3 air driven high-power turbines to drive the propellers (engine simulators) and various pieces of test equipment such as wiring, hydraulic tubes, clinometers and electric motors for airframe surfaces remote control, fitted with a variety of airframe shells.
This project specified and designed a wind tunnel tool to investigate the aerodynamic problems induced by the interaction of engine slipstream and airframe at high subsonic to transonic speeds. This tool was a large modular generic wind tunnel model, powered with air turbines for engine simulation.
First of all, the aircraft to be simulated with the GEMINI model were identified and fully defined (specification, shape and general arrangement). A number of alternative parts were included for later use. The wind tunnel operators were also involved in designing all the missing or new interfaces with their facilities (balances, stings, electronics). Then the model design started from both structural and instrumentation sides. Its heart was the skeleton, a primary structure on which the complete set of components (wings, fuselages, tails) was to be fitted in the ad hoc configuration. Its skin was also fully defined on manufacturing drawings. Another important part of the project was the power plant simulator itself. This consisted of an air driven turbine, the propellers and all related instrumentation, such as rotating balances designed to read thrust and torque during the tests. These pieces of hardware were specified and designed by specialists.
All the technical objectives of the project have been met. Even more, a consistent programme for wind tunnel testing has been initiated, including all the procedures necessary for its successful completion. More than 1000 documents (drawings and memorandums) have been produced.
1. Overall Description
Specifications and design of the basic rig including:
engine simulator units and their control equipment;
airframe parts (wings, fuselage,propellers,blades);
wind tunnel supports;
high pressure air supply including air bridges, flow meters.
This rig will have sufficient sophistication and flexibility (never achieved in the past) to allow for the following variations in aircraft configurations:
high and low wing setting;
single and counter rotating propellers;
wings designed for cruise Mach numbers between 0.5 and 0.8+;
tractor and pusher propellers;
wing mounted or rear fuselage mounted engines;
2. General Work Break-down
(a) Configuration studies and aerodynamic design: this basic item includes all preliminary studies necessary to assess all the constraints induced by the various aircraft configurations, define the possible geometries and to settle the set of functions with which the rig will have to comply. It also includes specifications of the generic model and all wind tunnel supplies (balances, sting support), associated with the studies.
(b) Drive units: design of advanced powerful (250 HP each), discreet and versatile "Engine Simulators".
(c) Rotating balances: study and design, by a multi-partner integrated research team, of torque/thrust propellers. Micro Rotating Balances to be fitted on the simulators.
(d) Propellers, model and skeleton design: structural design of an advanced 'versatile' skeleton and all associated airframe parts by multi-partner integrated research teams.
Funding SchemeCSC - Cost-sharing contracts
80038 Pomigliano D'arco - Napoli
WC2N 5JT London
1100 AE Amsterdam
581 88 Linköping