Experimental Facility to Measure Fouling Resistance in Condensers

Abstract

Heat exchangers are employed to transfer thermal energy between two fluids. Fouling is defined as the accumulation of deposits on the heat transfer surface which provides a resistance to the heat transfer, thereby decreasing the heat transfer capacity of the surface. The air conditioning industry has been under pressure to improve the efficiency of systems adopting these heat exchangers. The current thesis involves the design and construction of an experimental facility to measure the thermal and hydraulic performances of three brazed plate heat exchangers (BPHEs) of different geometries (chevron angles and aspect ratios) operating under controlled fouling conditions. Fouling tests conducted on the three BPHEs revealed that the chevron angle of the plates had a significant impact on the overall heat transfer coefficient (UA) and fouling resistance, a BPHE with a chevron angle of 300 had a UA 0.75 times less and a fouling resistance 15 times larger than a BPHE with a chevron angle of 630 and identical aspect ratio. The aspect ratio was found to have a slight impact on the UA and fouling resistance, a BPHE with an aspect ratio 4.1 had a UA 2 % greater and a fouling resistance 17 % lower than a BPHE with an aspect ratio of 2.1 and identical chevron angle.