The paper investigates parallel channel instabilities of natural circulation boiling water reactor. A thermal-hydraulic model is developed to simulate two-phase flow behavior in the natural circulation boiling water reactor (NCBWR) with the incorporation of ex-core components and recirculation loop such as steam separator, down-comer, lower-horizontal section and upper-horizontal section and th...

The effect of variation in thermal conductivity of light water reactor fuel elements on core response during loss-of-coolant accident scenarios is examined. Initially, a simplified numerical analysis is utilized to determine the time scales associated with dissipation of stored energy from the fuel into the coolant once the fission reaction is stopped. The analysis is then followed by full reac...

The paper demonstrates the development of a numerical algorithm to solve a set of nonlinear hyperbolic equations in time domain in Eulerian frame of reference using a characteristics based finite difference implicit scheme to analyze density wave oscillations in boiling water nuclear reactor. The present algorithm removes the uncertainties existing in literature over the treatment of boundary c...

This work describes an improved design for a nuclear fuel rod, which was developed using an experimental circuit that simulates the nuclear rod environment in a pressurized water reactor (PWR). The heat exchanger circuit runs atmospheric to high-pressure boiling water through an annular finned tube (153 fins), which is used to enhance confined heat transfer rates and guide the nucleate boiling ...

Nanofluids are engineered colloidal suspensions of nanoparticles in water, and exhibit a very significant enhancement (up to 200%) of the boiling Critical Heat Flux (CHF) at modest nanoparticle concentrations (50.1% by volume). Since CHF is the upper limit of nucleate boiling, such enhancement offers the potential for major performance improvement in many practical applications that use nucleat...