Numerical and experimental investigation of melting and solidification of molten salt in freeze valve

This study investigates the solidification and melting behavior of molten salt freeze valves, crucial c conducted to analyze the impact of geometric parameters on freeze valve performance. The experiments utilized ternary nitrate salt HITEC and involved precise temperature control and pressure regulation to induce solidification and melting. Numerical simulations, performed using ANSYS Fluent, incorporated a detailed physical model, including heat transfer and phase change phenomena. A grid sensitivity study was conducted to ensure the accuracy of the numerical results. The study demonstrated the significant influence of the flattened section thickness on the melting time. Thinner sections resulted in increased melting time. Additionally, the numerical simulations successfully captured the solidification and melting processes, validating the model's accuracy, and determining of accurate mushy zone parameter as 105. Simulations incorporating this mushy zone parameter indicated that the valve was estimated to open at approximately 870 s. The findings provide valuable insights into the design and optimization of freeze valves for various high-temperature energy applications, such as molten salt reactors and concentrated solar power plants.