The objectives of this paper are to develop advanced hybrid GAX cycles (HGAX) using NH3-H2O by combining absorption and vapor compression cycles, and to perform parametric analysis of system pressures and component sizes for performance enhancement. Four different HGAX cycles are developed - Type A (Performance improvement), Type B (Low temperature applications) Type C (Reduction of desorption temperature) and Type D (Hot water temperature applications). A compressor is placed between the evaporator and the absorber in Type A and Type B, and placed between the desorber and the condenser in Type C and Type D. It is found that the COP can be improved by 24% compared with the standard GAX cycle (in Type A) and the evaporation temperature of as low as -80°C can be obtained from the HGAX cycle (Type B). In Type C, the maximum desorption temperature can be reduced down to 164°C. Therefore, the corrosion problem, which becomes severe at higher temperature 200°C, can be completely removed. The maximum desorption temperature for the standard GAX cycle ranges 190-200°C. In Type D, the hot water temperature of as high as 106°C could be obtained. Therefore, Type D can be applied for space heating and panel or floor heating applications.
- Absorption system
- Mechanical vapour compression
ASJC Scopus subject areas
- Building and Construction
- Mechanical Engineering