A Literature Review On Heat Exchanger Air Side Fouling In Heating, Ventilation And Air-conditioning (HVAC) Applications

This paper provides a review on the fouling mechanism and its effect onto the performance of finned tube heat exchangers in HVAC systems. Fouling tends to degrade the performance of heat exchangers by decreasing the heat transfer coefficient and increasing the air-side pressure drop across the heat exchangers. Air side fouling depends on a number of factors on the air side, including type and concentration of fouling matter, size of particles in the fouling matter, and air velocity. Additionally, it depends on the heat exchanger design, e.g. heat exchanger geometry, fin geometry, and fin spacing. Various studies indicate that the effect of fouling on air pressure drop is higher than its degrading effect on heat transfer coefficient. Studies on heat exchanger fouling in HVAC systems indicate that the actual effect of the fouling onto system efficiency additionally depends on the employed refrigerant.