Analysis and validation of a thermal hydraulic dynamic model for the parabolic trough solar field

Highlights: • A thermal hydraulic dynamic model for a parabolic trough solar field is developed. • The model is validated with experimental data obtained from a pilot plant. • Thermal hydraulic behavior of the solar field is analyzed in detail. • A method for balancing the flow distribution is improved upon and verified. In this paper, a thermal hydraulic dynamic model (THDM) is developed to improve the efficiency and controllability of a parabolic trough solar field (SF). The THDM is divided into a hydraulic submodel and a thermal submodel; these two submodels interact via flowrate and temperature of the heat transfer fluid. Three experimental cases are then used to validate the THDM based on the Badaling 1 MW parabolic trough solar thermal power pilot plant. In Case 1, the compared results show good agreement between the simulated and measured values without the effect of the control valve, the root mean square errors (RMSEs) for the flowrate and the outlet temperature are less than 0.3 m³/h and 8 °C, respectively. In Case 2, the compared results maintain good agreement under the influence of the control valve, the RMSEs for the flowrate and the outlet temperature are less than 1 m³/h and 10 °C, respectively. In Case 3, a method for balancing the flow distribution is tested using the pilot plant. The results indicate that this method enables the standard variance of the flow distribution to approach zero by changing the valve position to the calculated values.