Experimental Study of Explosion Characteristics Caused by High-Temperature Sodium Leakage from a Heat Pipe into Air

Abstract

Heat pipe cooled reactor is an advanced reactor design that uses an array of in-core heat pipes for passive heat transfer. In heat pipe leakage accident, combustion or even explosions produced by high-temperature sodium reacting with the air can cause core damage. In this paper, the explosion characteristics of the sodium leakage are studied by analyzing of physical phenomena and discussing the pressure pulse and temperature rise. Based on explosion phenomena, this paper proposed a phenomenological model of sodium heat pipe leakage. A small explosion, accompanied by yellow light, occurred at the moment of the sodium heat pipe leakage. The overpressure increased with an increase in the initial temperature and break size. The results of this paper include experimental phenomena and quantitative analysis of explosive power, which provide a basis for the development of subsequent mechanism model and safety evaluation of heat pipe cooled reactor.

Keywords: sodium heat pipe, high temperature, explosion, leakage