Masters Theses


Lifeng Wang


"Emergency core cooling system (ECCS) has been studied extensively for reactor safety. Emergency core cooling system (ECCS) is designed to make sure the reactor core it is protected by providing sufficient heat removal during accident conditions. In a loss-of-coolant-accident (LOCA) scenario, the ECCS is designed to take over the reactor core cooling by drawing water from a reservoir or tank. Voids may be introduced into the ECCS through a variety of means leading to total or partial loss of suction supply, or through gas depressurization resulting from difference in gas saturation pressure and ambient pressure. The transportation of voids through the ECCS train may lead to malfunction and/or degeneration of the ECCS - a safety concern. The issues associated with void introduction in ECCS include but are not limited to pipe damage, suction pump failure and stress-induced failures. In this thesis, simulations were performed to determine the maximum void allowable at a gas accumulation point in the ECCS piping system. The limiting criterion was set at 5% maximum void fraction at the inlet to the any of the ECCS pumps. The simulation was performed using FLUENT 6.3 - a computational fluid dynamics (CFD) code. The maximum void allowable in the ECCS pump was determined for 2 ECCS models. The allowable void at the accumulation point in each models are 2.1447 ft³ for Model 1 and 1.1503 ft³ for Model 2. The times at which the maximum void fractions were reached at the pump entry are 28 and 22 seconds for Models 1 and 2, respectively"--Abstract, page iii.


Alajo, Ayodeji Babatunde


Nuclear Engineering and Radiation Science

Degree Name

M.S. in Nuclear Engineering


Two supplementary files included.


Missouri University of Science and Technology

Publication Date

Spring 2013


viii, 45 pages

Note about bibliography

Includes bibliographical references (pages 50-52).


© 2013 Lifeng Wang, All rights reserved.

Document Type

Thesis - Open Access

File Type




Subject Headings

Pressurized water reactors -- Emergency core cooling systems -- Testing
Computational fluid dynamics -- Mathematical models
Two-phase flow -- Mathematical models
Pressurized water reactors -- Loss of coolant
Water cooled reactors -- Loss of coolant

Thesis Number

T 10307

Electronic OCLC #