Application of the Simple Analytical Approach to Calculate Pressure Drop in Liquid Nitrogen Two Phase Flow Over Large Distances Using Hoses

Abstract

In order to repair/replace passing shutdown cooling (SDC) isolation valves, three ice plugs are required in the SDC rooms 13 m below the ground level (elevation 87.7 m) to provide the necessary isolation. The results in this paper show that 1½" corrugated hoses can provide adequate LN2 from the tanker at ground level (elevation 100 m) to the SDC rooms 120 m from the tanker using the existing ¾" containment penetration of the feeder freezing system to maintain these three ice plugs. The calculations also show that if ¾" hoses are used exclusively, the pressure drop is significant enough to prevent any LN2 supply to the SDC rooms.