Resuspension Experiments of Cleanroom Particles

Satellite integration is conducted in a cleanroom to safeguard surfaces and instruments from contamination. Nevertheless, particulate contamination is frequently observed on satellite surfaces and instruments. Flushing, which involves the injection of a gas, is employed to reduce relative humidity and protect hygroscopic elements of the instruments. However, flushing carries the risk of displacing particulate contamination by resuspension. Furthermore, the resuspension of particles may also occur during launch as a result of depressurization and vibrations. The objective of this study was to experimentally investigate the resuspension of typical particles found in satellite assembly cleanrooms. To this end, an experiment was developed that allowed the resuspension to be filmed with high-speed cameras and used to obtain minimum flow velocity values for the resuspension of self-gripping fastener particles and textile fibers. This will help the contamination engineers limit flow velocity levels to avoid recontamination of previously cleaned surfaces. A method was also developed to measure adhesion force as a preliminary estimate to be used in further modeling work.