A simulation model for a vertical U-tube steam condenser in which the condensate is stored at the bottom well is developed in this paper. The U-tubes carrying the coolant are partially submerged in the stored condensate and thus the bottom well acts as a heat exchanger. The storage of hydraulic and thermal energies is represented using a coupled pseudo-bond graph model. Advection effects are mo...

The ARIES-ST (Spherical Tokamak) is to investigate the attractiveness of a low-aspect-device as the confinement concept for a fusion power plant. The key driven force of the ST design is caused by the center column conductor. The design selected is a water-cooled Cu normal conductor. This selection has a major impact on the blanket design and selection, tritium breeding and over-all power balan...

A modular DCLL blanket is selected as the reference concept in the ARIES-CS power plant study. This concept is characterized by the following features: 1. Eutectic lead lithium alloy Pb-17Li serving as breeder and coolant (“self-cooled breeding zone”); 2. Helium-cooled FW and blanket structure made of the MF82H Reduced Activation Ferritic Steel (RAFS); 3. Flow channel inserts (FCI) made of SiCc...

The continuous stirred-tank reactor with uncertain parameters was stabilized in the open-loop unstable steady state using the robust model predictive control. The gain matrices of the robust state-feedback controller were designed using the nominal system optimization and the quadratic parameter-dependent Lyapunov functions. The controller was verifi ed by simulations using the non-linear model...

In this paper, we are interested in modelling the flow of the coolant (water) in a nuclear reactor core. To this end, we use a monodimensional low Mach number model coupled to the stiffened gas law. We take into account potential phase transitions by a single equation of state which describes both pure and mixture phases. In some particular cases, we give analytical steady and/or unsteady solut...

the main purpose of this study is to perform numerical simulation of nanofluids as the coolant in vver-440 fuel rod bundle. the fuel rod bundle contains 60 fuel rods with length of 960 mm and 4 spacer grids. in vver-440 fuel rod bundle the coolant fluid (water) is in high pressure and temperature condition. in the present thermo-hydraulic simulation, water-al2o3 nanofluids containing various vo...

New pressure drop / flow rate measurements coupled with a previously reported heat transfer database have resulted in new friction factor and heat transfer correlation equations for fan-driven impinging flow through square arrays of cylindrical cross-section pin-fins. The correlation equations include the effect of coolant flow rate, pin-fin density and pinfin height. A comparison with a simila...

Measurements of mean velocity, turbulence intensity, and turbulent shear stresses are presented for the mixing region of a film cooling situation in which the coolant is laterally injected. Measurements are performed using triple-wire anemometry so that all three mean velocity components are documented. Such measurements also give Reynolds stress terms in the flow field. Flow with one row of fi...

As part of the reactor dynamics activities of FZK/IRS, the qualification of a detailed 3D CFD model of a reactor pressure vessel is a key step in safety evaluations for improving predictive capabilities and acceptability of commercial CFD tools in reactor physics. The VVER-1000 Coolant Transient Benchmark, initiated by OECD, represents an excellent opportunity for validation. In this work a CFD...

Tin–lithium (Sn–Li) has been identified as a candidate liquid metal coolant for fusion power reactors. Sn–Li coolants offer a number of advantages compared with pure lithium. The vapor pressure of Sn–25Li (0.25 Li mol fraction) is a factor of 1000 lower than that of pure Li, which allows an increase in coolant temperatures by as much as 450 K. Experimental data of the stability of ceramic mater...