Performance Evaluation and Evaporation Loss Prediction in Counter Flowinduced Draft Geothermal Wet Cooling Tower Type Through Computational Fluid Dynamics (CFD) Simulation

Abstrakt

Cooling towers are critical components in geothermal power generation systems, playing a vital role in maintaining thermal efficiency and managing water resources. This study investigates the thermal performance and water loss due to evaporation in an induced draft counter-flow cooling tower using a modeling and simulation approach based on Computational Fluid Dynamics (CFD). Validation of the simulation results against actual data demonstrated high accuracy, with an error margin of 1.8%, indicating that CFD is a reliable method for analyzing and optimizing cooling tower design Simulation results show that increasing the hot water inlet temperature from 35°C to 49°C leads to a rise in evaporation loss from 5.0 kg/s to 13.0 kg/s (CFD), while the ASHRAE method yields higher values, ranging from 5.5 kg/s to 14.5 kg/s. For variations in hot water mass flow rate (423–845 kg/s), the ASHRAE method exhibits a linear increase in evaporation loss, whereas CFD results remain relatively stable. Additionally, increasing the hot water mass flow rate causes the cold-water outlet temperature to decrease from 21°C to 11°C, accompanied by a reduction in system effectiveness from 92% to 86%. Furthermore, increasing the cold air inlet velocity from 3.5 m/s to 6.5 m/s raises the evaporation loss from 14.5 kg/s to 16.0 kg/s (CFD) and significantly enhances system effectiveness from 11% to 91%. Overall, the findings demonstrate that CFD simulations provide realistic performance estimations compared to empirical methods, particularly under dynamic operating conditions.