R134a-DMF Vapour Absorption Refrigeration System (VARS) with Plate Heat Exchangers

The conventional vapour compression refrigeration systems (VCRS) require high-grade electrical energy for their operation. The Vapor Absorption Refrigeration systems (VARS) are also called heat operated or thermal energy-driven systems. VARS offer many advantages like it offers flexibility to utilise any sort of low grade, low-cost heat energy to produce cooling and thus giving high savings in operating costs. The vapour absorption system uses heat energy which may be industrial waste heat or solar heat for its operation and is a good alternative for electrically operated vapour compression system. R134a-DMF system is considered attractive than any other R134a-absorbent combinations in VARS. Compact heat exchangers are gaining widespread acceptance, and new PHE types have been developed. The brazed PHE (BPHE) has been developed for two-phase heat transfer, particularly as evaporators and condensers. In brazed and fully welded PHE, no frame is needed to hold the plates in place. It was observed that the local absorption rate of the bubble mode is higher than that of falling film mode.