Rewetting of a vertical surface with internal heat generation

Conference · Sat Jan 01 04:00:00 EST 1977 · AIChE Symp. Ser.; (United States)

OSTI ID:6179053

Yao, L S

The rewetting of a vertical surface has been a subject of great importance as a result of emergency core cooling considerations in the hypothetical loss-of-coolant accident in water reactors. Numerous theoretical and experimental studies have been undertaken to investigate the rate of wet front advance; however, the effect of fission-products decay heating on wet front advance has never been demonstrated. A one-dimensional model is inadequate to describe the physical phenomenon, since the transient conduction of internal generated heat across the fuel rod clad may play a dominant role. This paper presents a two-dimensional analysis of conduction-controlled rewetting of a vertical surface with internal heat generation. The physical model consists of an infinitely-extended vertical slab with one side of the surface, the dry region and the wet region, associated with constant heat transfer coefficients, and the other side of the surface with constant heat flux to simulate the fission products decay heating. The governing equation is solved by applying the approximate integral method. Then the functional dependence of the rewetting rate is obtained by the condition that the hot surface can only be wetted when its temperature is below the rewetting temperature. The critical internal heat generation rate is obtained by setting the Peclet number equal to zero, which gives the minimum rate of internal heat generation to prevent the hot fuel rod being rewetted.

• Research Organization: Rand Corp., Santa Monica, CA
• OSTI ID: 6179053
• Report Number(s): CONF-760816-
• Conference Information: Journal Name: AIChE Symp. Ser.; (United States) Journal Volume: 73:164
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
220900* -- Nuclear Reactor Technology-- Reactor Safety
ACCIDENTS
AFTER-HEAT
ECCS
ENGINEERED SAFETY SYSTEMS
FUEL ELEMENTS
LOSS OF COOLANT
REACTOR ACCIDENTS
REACTOR COMPONENTS
REACTOR PROTECTION SYSTEMS
REACTORS
REWETTING
TWO-DIMENSIONAL CALCULATIONS
WATER COOLED REACTORS