A review of heat exchanger fouling in the context of aircraft air-conditioning systems, and the potential for electrostatic filtering

This paper presents a focused literature review to understand the common problem of fouling of air-conditioning heat exchangers aboard aircraft, with the academic consideration to employ electrostatic precipitation to remove airborne particulate matter. Particulate matter suspended in air, is carried through the matrices of aircraft environmental cooling systems. The deposition and build up of such contaminants affects the thermal performance of cooling systems and leads to component failure, expensive repairs and loss of service of an aircraft. Although there have been many publications of material pertaining to heat exchangers and fouling, very little publications specifically to aircraft air-conditioning systems or failures have been published. Nonetheless, the literature review indicates that sizes and distribution of particulate matter including Reynolds numbers and rates of deposition have been established in previous papers. The novel approach to this industrial problem has been to evaluate the operational problem of aircraft air-conditioning systems, identify local factors, and to consider the use of means of protection employed in other non-aerospace industries. It is believed the application of electrostatic precipitation could potentially aid prevention of fouling particulate matter on aircraft air-conditioning heat exchangers. (c) 2009 Elsevier Ltd. All rights reserved.