A preliminary investigation of fouling in brazed plate heat exchangers.

摘要

This thesis reports a preliminary investigation of combined particulate and precipitation fouling on the water-side of brazed plate heat exchangers (BPHE) used as water-cooled condensers. An experimental facility to study fouling on water-side of brazed plate-type (BPHE) condensers has been designed and constructed. The test facility was designed based on standard rating conditions to measure performance of water-cooled refrigerant condensers. This thesis also covers a methodology to compose high fouling potential water. Experiments were performed on three BPHEs that have different geometries and chevron angles using high fouling potential water. The experimental results show that the fouling resistances gradually increase with Langlier Saturation Index (LSI) values, which is an index used to determine the saturation level of CaCO3 in water. In addition, a strong effect of internal geometry of the plates on the asymptotic fouling resistances was observed. The asymptotic fouling resistance for the BPHE with a 60° chevron angle is almost 10 times more than the asymptotic fouling resistances of the BPHEs that have 27° chevron angles.