Modeling of A Dry Cooling Unit Operated With Supercritical Co2 In 25 Mw Nddct
Dry cooling towers are mostly employed in thermal power plants due to scarcity of water, utilized energy consumption and reduced maintenance cost associated with the mechanical fans. Different types and shapes of natural draft dry cooling towers (NDDCT) are used in many thermal and power plant industries whose main purpose is to generate air flow through the finned tube heat exchanger bundles by the influence of buoyancy due to density difference between fresh ambient air and warm exit air. In the present article, we develop an one dimensional MATLAB code to design a 25 MW capacity NDDCT with detailed specification of finned tube heat exchanger bundles operated with supercritical CO2 (sCO2). The tower height, tower inlet and outlet diameters, number of heat exchanger bundles and total air side and tube side areas are evaluated after accomplishing the design of the tower according to specified. The profiles for temperature, heat rejection and convective heat transfer coefficient for both air side and sCO2 side and the characteristics of pressure drop are comprehensively investigated to evaluate the performance the an air cooled heat exchanger unit.
Keywords - Cooling tower, supercritical CO2, heat transfer, heat exchanger.