Numerical Evaluation of Coolability Limits of External Reactor Vessel Cooling Using an Improved Thermal-Hydraulic System Analysis Code

Table 1

Convection boundary types in the heat transfer package of the MARS-KS code and newly implemented indices for the lower head of the reactor vessel [25].

Index	Geometry type	CHF model	Nucleate boiling model
1, 100, 101	Default	Lookup table [24]	Chen [26]
102	Parallel plates
110–113	Vertical rod bundle		Chen-Inayatov [25]
134–137	Horizontal rod bundle	Folkin and Goldberg [25]	Polley, Ralston, and Grant [25]
190	Downward-facing hemisphere	ULPU-II correlation	Chen [26]
191		Toshiba correlation
192		SULTAN correlation