RUAG AEROSPACE
In order to fulfil those needs RUAG Aerospace is constantly improving its wind tunnel equipment, using mostly internal knowhow and experience, with notable achievements in the last four years. In 2005, new data acquisition (DAE) hardware was introduced. Additionally, the old control systems (COSYS, COntrolled SYStems used, for instance, for model manipulators) were replaced with up-to-date hardware, new control software and intelligent user interfaces that allow quick reactions to incoming test results. The latest step was completed in 2007 with the commissioning of the new in-house-developed wind tunnel Master Control Software (Master Computer Program, MCP) that provides overall control over the test and measurement sequences. A sketch of the environment in which these upgrade activities took place and the systems which were affected is given in the figure [below]. It shows the relations between the MCP, the COSYS (such as model manipulators and wind tunnel controls), the DAE, the experimental facilities and the test objects (wind tunnel models) in the context of the associated technologies and RUAG’s capabilities.
Data Acquisition (DAE)
Dassault Falcon 7X (scale 1:8.5). Low-speed wind tunnel tests for stability & control as well as for aero database definition.
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n commercial wind tunnels such as in RUAG Aerospace’s
facility in Switzerland, customers range widely: from aerospace and automotive to civil engineering and sports, etc. Consequent testing needs differ greatly. In fact, not one test setup is exactly the same as the other and often customer-specific equipment is necessary. The efficient and manageable implementation of all the different customer needs in one single facility requires specialists from a number of fields (such as electronics, mechanics, sensor technology, software and testing) plus a high degree of flexibility in the wind tunnel and its equipment, be it mechanical, electrical or software. What all customers have in common is a need for accurate and repeatable results, obtained at a high productivity level, so that a maximum return can be obtained within the often severe time and budget constraints.
2009 | WIND TUNNEL INTERNATIONAL
The success of a wind tunnel test depends considerably on the availability of a high-quality data acquisition system, able to resolve with great certainty the minute force variations sensed by the instrumentation. The Aerodynamics Center is relying on the MGCplus technology of Hottinger Baldwin Messtechnik (HBM) for data acquisition tasks in its wind tunnels (with the exception of static pressures where PSI pressure scanners are used). The system offers a choice of different amplifier types which, when combined with the proper connection boards, enable meeting the highest accuracy demands of a wide variety of sensors. Concurrent, dynamic measurements at sampling rates up to 2,400 Hz can be performed with this system. For each of RUAG’s wind tunnels, the hardware components have been integrated in a cabinet together with various monitoring devices. To comply with ISO-9001 standards, periodic calibrations are necessary for the entire measurement chain. In a high-tech wind tunnel environment, downtime must be minimized, as costs per time unit are rather high due to the intrinsic substantial assets and operating costs. Therefore a special on-site calibration system/ procedure with traceability to national standards was developed. The system is certified in accordance to RUAG standards for calibration of HBM equipment and is also available as a service for external customers. 79