Mathematical Modelling and Analysis of the Thermal Characteristics of a Thermosiphon Solar Water Heating System
Year: 2026
Type: conference-paper
Abstract: This article presents a mathematical model and analysis of the operating modes of a solar water-heating system with pump circulation. The aim of the study is to evaluate the daily dynamics of the system’s main thermal parameters based on calculated time-dependent values of solar radiation, ambient temperature, heat loss coefficient, useful heat flux, residual model error, and pump operating mode. The simulation results show that solar radiation intensity ranges from 0 to 860–880 W/m2, with the active phase of solar exposure occurring approximately from 6:00 to 18:00, and maximum values being reached around midday. The ambient temperature varies between approximately 3 and 17 °C over the course of a day, while the heat loss coefficient ranges from 8.1 to 11.0 W/(m2·K). The system’s useful heat flux varies from 0 to 0.63–0.65 kW, reaching a maximum during the period of peak solar activity. It has been established that the system’s active heat output is primarily observed from 8:00 to 16:00. An analysis of the residual error between the calculated and measured temperature values showed that, in most cases, the deviations do not exceed approximately ±1.0 °C, which confirms the satisfactory adequacy of the developed model. Additionally, it is shown that the pump operates in a stable cyclic mode with binary states 0/1, ensuring periodic circulation of the coolant during the time interval under consideration. The results obtained confirm the feasibility of using the proposed model to predict the system’s energy efficiency, analyze pump control modes, and select optimal operating conditions for solar water-heating systems.
Language: English
Field: Energy
Domain: Physical Sciences
Open Access status: hybrid
OpenAlex ID: W7223393453