SENSITIVITY ANALYSIS OF STRUCTURAL PARAMETERS FOR A LOOP THERMOSYPHON IN THE SOLAR WATER HEATING SYSTEM

A loop thermosyphon (LT) enables efficient long-distance heat transfer between the evaporator and condenser, offering significant technical advantages in solar water heating systems. This study develops a generalized mathematical model of LT based on energy, momentum, and mass conservation principles, coupled with a solar water heating system. Numerical simulations assess the impact of static liquid column height, collector inclination angle, condenser pipe diameter, and length on system performance. Sensitivity analysis identifies optimal parameter values for improved heat transfer and circulation stability. The results reveal that the static liquid column height is decisive in the system's heat transfer efficiency and circulation stability. The collector inclination angle changes significantly affect the balance between the gravitational driving force and pressure drop within the evaporator. The diameter and length of the condenser pipe notably influence the condensation efficiency and circulation flow. An excessively large or small condenser diameter negatively impacts the flow rate and heat transfer efficiency, while an overly long condenser pipe may lead to reduced mass flow rate, causing performance degradation. Based on the analysis of heat transfer performance and circulation stability, the optimal ranges for key structural parameters are determined. The findings indicate that appropriately increasing the static liquid column height, optimizing the condenser length and diameter, and adjusting the collector inclination angle can significantly enhance system performance. The system achieves optimal performance when the static liquid column height is 1 m, the condenser length is 5 m, the pipe diameter is 0.016 m, and the collector inclination angle is 40°.