Coolant stratification in nuclear power facilities

Computational and experimental studies of the structure of the motion of stratified coolant and its temperature regime are performed on models of different elements of the circulation loops of fast and thermal reactors. The investigations have shown that in the presence of stable stratification thermogravitational forces bring about the formation of stagnant and recirculation formations with large temperature gradients and pulsations at interfaces. The data obtained show that stratification phenomena must be taken into account when validating the reliability of the control, safety, and nominal service lives of nuclear power facilities.