Figure 3 Solid desiccant- hybrid cooling system
The pre-cooled air by solid desiccant cooling is sent to the vapor compression air conditioning system. The air is cooled to comfort supply condition which is specified as point 4 which is sent to the cabin to address the heat load.
The working of the solid desiccant cooling system is simulated by the object-oriented programming BLUEJ simulation platform. This is a looping system and the system achieves steady-state conditions through an iterative procedure.
For equipment like the desiccant wheel, the desired humidity ratio is attained through an iterative process that involves incremental increases in the air humidity ratio. The program continues to run until it reaches a steady state (∆T<0.001), which means that the temperature between two iterations must be less than 0.001°C at all the stages in the solid desiccant loop. Initially, the system was modeled using ideal process assumptions. Non-idealities in the process are added later to make the model more effective in making accurate predictions of outcomes in real-world situations. The operating points of all the equipment in the loop are given as desired operating conditions via a notepad.
The system is tested for numerous hot-humid conditions. The operating conditions where the system is tested are given in Figure 4. The ambient conditions for which the system is tested are in the humidity ratios of 21, 22, and 28 gkg-1 d.a. These conditions are taken from the experimental work reported by Venkatesh et al [18].