Abstract
To simulate the fuel-coolant interaction under the easily controllable condition, the water and the liquid nitrogen were used respectively as the molten fuel and the coolant in this study. To initiate the interaction, the water was injected into the cylindrical chamber to come into contact with the liquid nitrogen. The experiments were conducted with two key parameters, the water/liquid nitrogen volumetric ratio and the water injection pressure, to study their effects on the interaction. The experiments were conducted at the different water injection pressures with various initial volumetric ratios for water and liquid nitrogen. The pressure spikes and the ice debris observed from the experiments confirmed the existence of the strong interaction between the water and the liquid nitrogen. The occurrence of the pressure spikes and the times of their inceptions at the different conditions were used to create a diagram to indicate the preferable conditions for the strong interaction. The propagation speed of an observed pressure spike was estimated to be comparable to the theoretical sound speed of the liquid nitrogen/nitrogen vapor mixture. This result suggested the possibility of the vapor explosion interaction between the water and the liquid nitrogen similar to that observed in the fuel-coolant interaction.