I'm guessing the action of the impeller sucking air through itself would be enough to keep a reasonable amount of dust from collecting in the gap. It'll probab

I'm guessing the action of the impeller sucking air through itself would be enough to keep a reasonable amount of dust from collecting in the gap. It'll probably fall apart in heavy dust environments, but most things do anyway. To quote the pdf: """Rotation of the heat sink at several thousand rpm also provides a potent remedy to the longstanding problem of heat exchanger fouling. Consider for example the CPU cooler shown in Figure 1. The finned, metal heat sink cannot be seen because it’s covered in dust. But the fan blade, which operates in the same environment, is for all intents and purposes perfectly clean. This contrast in dust accumulation is at first startling, but in hindsight entirely expected. The air bearing heat exchanger therefore provides a complete solution to the problem of performance degradation due to heat sink fouling. In specialized applications involving extremely high particle loading, a straight-radial rather than backward-swept fin design would likely be used [Bleier, 1997]."""