Lighting up the sun at Intespace !

With Simdia, a solar simulator combined with a thermal vacuum simulator, Intespace has shaken up the product lifeline concept. While the thermal vacuum simulator has been operational since the seventies, the solar simulator has been out of service for many years now. Yet over the last few months, Intespace teams have been working to conquer a genuine technical and industrial challenge: to turn this simulator into the best means in the world for tests, reproducing the environment required for scientific expeditions to Mercury and to the Sun itself. The space industry is looking for an effective way of reproducing extreme or high radiation environments for its missions to Mercury and the Sun. This is no small challenge given that to effectively simulate solar radiation, specific technical difficulties need to be solved including: creating a uniform flow, undisturbed by flickering of the lamp, and parallel, because near the sun light arrives practically parallel.

At the ESA, there is already a recent simulator equipped with a lamp placed nearly 5 meters from the specimen which makes it possible to obtain a parallel direct flow. However, this flow is not homogenous due to the flickering of the 25000 watt lamp that generates it. For its part, Simdia is designed such that its flow is highly homogenous thanks to a set of optical blocks, mirrors and lenses which do away with the flickering of its six Xenon 6500 watt lamps.

Certainly the flux is conically divergent but what at first sight would seem to be a handicap nonetheless offers two advantages. Being conical, it can pass through a smaller porthole which is in turn less complex to make and maintain because the cost of polishing a porthole obscured by residues generated at high temperatures is calculated per m2 Simdia is not only economical but also high performance because its conical flux, designed to illuminate a specimen placed in the center of the chamber at a solar constant of 1 (intensity of solar radiation in earth orbit) on a one meter diameter, enables the radiation intensity to be considerably increased by moving towards the source in the narrow part of the cone.

Drawing of Simdia

A solar constant of 10 is achieved on a diameter of around forty centimeters in this way or even 13 on a diameter of over thirty centimeters. And this is what opens up new markets and positions it at the top of the solar simulator range.

Over the last few months Simdia has been given a new lease on life: replacement of electrical power supplies, maintenance of the cooling systems, cleaning and realignment of the optical units, redefinition of mean control parameters, refurbishment of the old mapping, implementation of appropriate procedures, etc. For the Intespace teams, to be able to give new life to this 'sleeping sun' in less than four months in tandem with a heavy test plan load, has been a real technical challenge. Nonetheless it's been successful: Simdia's technical acceptance was achieved in August 2013. Operational acceptance was completed in September. This is a big, small step because it means that Simdia can now participate in scientific missions such as Bepi colombo planned for 2017, or the Solar Orbiter mission programmed for 2020.

With Simdia, Intespace is positioning itself very favorably on a future niche market, serving ambitious scientific missions while at the same time minimizing development and operating costs. Coming up with a bright idea on how to turn a sun back on again is also creativity and innovation!

 Read the white paper about Simdia test facility presented during the European Conference on Spacecraft Structures

 Learn more about Intespace thermal test facilities





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