International Journal of Heat and Mass Transfer, Vol.118, 193-200, 2018
Simulation analysis of solution transportation absorption chiller with a capacity from 90 kW to 3517 kW
The utilization of waste heat instead of fuel combustion is effective in reducing primary energy consumption to mitigate global warming problems. As waste heat sources are not necessarily located close to areas of heat demand; one of the difficulties is that waste heat must be transferred from the heat source side to the heat demand side, which may require the transportation of heat over long distances. From this point of view, we proposed and examined a new idea of heat transportation using ammonia-water as the working fluid in the system named the Solution Transportation Absorption chiller (STA). Our previous studies of the STA were mainly based on the experimental investigation with the STA facility where the cooling power was 25 RT (90 kW). Thus, the Coefficient of Performance (COP) of STA was found to have almost the same value of 0.65 with conventional absorption chillers without depending on the transportation distances. The simulation using AspenHYSYS also examined the same experimental condition. The experimental data showed good agreement with the simulation calculation. In this study, we examined the large-scale cooling power of the STA on the simulation. The intention of this study was to analyze sensitivity with large cooling capacities, the examined cooling powers were from 90 kW (25 RT) to 3517 kW (1000 RT). All cooling power achieved around COP 0.64 including pump power consumption. In addition, we performed a dynamic simulation. The results showed that pipeline size did not affect the cooling capacities and mass flow rates. Furthermore, the stability time of the cooling capacities and mass flow rates were almost the same regardless of the pipeline size and cooling capacity. In other words, the STA may achieve the same COP despite having various complex conditions compared with the conventional absorption chiller. (C) 2017 Elsevier Ltd. All rights reserved.
Keywords:Absorption chiller;Thermal energy transportation;Solution transportation;Ammonia-water;COP;Simulation