الفهرس | Only 14 pages are availabe for public view |
Abstract The thermal hydraulic characteristics of a steam gener¬ator ( SG ) control the heat rejection capability of the primary heat source in nuclear power plants ( NPP’s Therefore, SG’s play an important role in determining the safety of the NPP’s. It is very important to study all physical processes which determine the thermal performance and operational behaviour of the SG under’ steady state and transient conditions. This study should include coupled two-phase flow, natural circulation, and heat transfer phenomena The main objectives of the present study are : (i) To develop a modified mathematical model for vertical U tube natural circulation SG to treat single and two phase flows in transient and steady state cond itions. (iJ)To determine the mass flow rate, circulation ratio, temperature and enthalpy distributions at different power levels. (iii)To develop computer program to execute the numerical solution of all equations involved in the problem. The mathematical formulation consists of the app-ication of conservation laws to three components in the secondary side designated as the tube bundle elements, ( ten control volumes, five for hot leg and five for cold leg ), downcomer |