Comprehensive exergetic study of regenerative Maisotsenko air cooler; formulation and sensitivity analysis

Highlights: • A new exergetic analysis is provided for M-cycle cooler. • Outlet characteristics of cooler is evaluated via analytical solution. • Impact of all thermal/flow parameters on exergetic characteristics are discussed. • Lower air flow rates provided higher exergetic efficiency. • Higher air inlet temperature or flow rate increased exergy destruction. -- Abstract: Great achievements have been made in the researches of thermal characteristics of Maisotsenko air cooler. However, a clear gap is still in existence on exergetic behaviour of M-cycle coolers. The significance of exergy analysis of M-cycle air coolers is highlighted when they were employed as a temperature reducer of intake air of gas-turbines in power plants to improve the efficiency of the system. Obviously, economic analysis of any thermodynamic system underlines the exergetic evaluations of the whole parts of the system which has been resulted in the emergence of professional expressions such as "exergoeconomic" and "thermoeconomic". This paper reports a comprehensive exergetic formulation and analysis of regenerative M-cycle air cooler which can be employed in air conditioning industry and other applications of M-cycle cooler for better decision making. Higher inlet air mass flow rate, inlet air temperature and air flow ratio between two channels caused further exergy destruction. Exergetic efficiency of humid air is found more than the exergetic efficiency of dry air in M-cycle coolers. In order to prevent the severe exergy destruction through the cooler, the air velocity along the channels should not have large value. It is noted that, in the same total inlet air flow rate, the air velocity along the channels can be controlled by the numbers of the employed parallel plates in the designing process of M-cycle based on the second law of thermodynamics.