This study considers optimization of the fuel assembly arrangement in the initial core loading of the 200 MW nuclear heating reactor (NHR-200). The enrichment of the fuel assemblies is used as the control variable wit...This study considers optimization of the fuel assembly arrangement in the initial core loading of the 200 MW nuclear heating reactor (NHR-200). The enrichment of the fuel assemblies is used as the control variable with the objective to minimize the power peaking factor. The optimization methods are applied indirectly because it is difficult to directly relate the control variable and the object function in a single equation. Therefore, the solution uses linearized functons which are solved with linear programming. The corrected simplex method is used to solve the optimal problem. Useful engineer software has been designed and used in reactor physics design.展开更多
The 5MW nuclear heating reactor is an integral natural circulation reactor. The rupture of the coolant penetrating tube is a typical accident causing coolant loss. When the water level drops down to the upper edge of...The 5MW nuclear heating reactor is an integral natural circulation reactor. The rupture of the coolant penetrating tube is a typical accident causing coolant loss. When the water level drops down to the upper edge of the inlet of the heat exchanger, the natural circulation stops. This influences the core cooling and the stability of the main loop. A series of tests showed that there is a stable drop of pressure, and the heated element temperature is not too high to cause burnout. But the backward flow or flow oscillation in the primary coolant circuit occurs when the flow breaks completely in the end. The whole flow process is described and the mechanism is discussed.展开更多
The two-phase flow instability that can occur in a natural circulation system is of importance in the design of nuclear heating reactors. The time domain code RETRAN-02 and the frequency domain code NUFREQ were applie...The two-phase flow instability that can occur in a natural circulation system is of importance in the design of nuclear heating reactors. The time domain code RETRAN-02 and the frequency domain code NUFREQ were applied to estimate the instability boundary and the effects of such parameters as pressure, inlet resistance and riser height in NHR-5 and an experimental loop. The results of the calculations and the experiments are in good agreement. Nonlinear density wave oscillations were analyzed using the RETRAN-02 code. The theory of nonequilibrium thermodynamics was used to find an explicit criterion to estimate the threshold of the stability. Experimental simulation of the nuclear feedback density wave instability was also carried out in a test loop using. computer controlled electric power.展开更多
文摘This study considers optimization of the fuel assembly arrangement in the initial core loading of the 200 MW nuclear heating reactor (NHR-200). The enrichment of the fuel assemblies is used as the control variable with the objective to minimize the power peaking factor. The optimization methods are applied indirectly because it is difficult to directly relate the control variable and the object function in a single equation. Therefore, the solution uses linearized functons which are solved with linear programming. The corrected simplex method is used to solve the optimal problem. Useful engineer software has been designed and used in reactor physics design.
基金the National Natural Science Foundationof China!(No.19872 0 40
文摘The 5MW nuclear heating reactor is an integral natural circulation reactor. The rupture of the coolant penetrating tube is a typical accident causing coolant loss. When the water level drops down to the upper edge of the inlet of the heat exchanger, the natural circulation stops. This influences the core cooling and the stability of the main loop. A series of tests showed that there is a stable drop of pressure, and the heated element temperature is not too high to cause burnout. But the backward flow or flow oscillation in the primary coolant circuit occurs when the flow breaks completely in the end. The whole flow process is described and the mechanism is discussed.
文摘The two-phase flow instability that can occur in a natural circulation system is of importance in the design of nuclear heating reactors. The time domain code RETRAN-02 and the frequency domain code NUFREQ were applied to estimate the instability boundary and the effects of such parameters as pressure, inlet resistance and riser height in NHR-5 and an experimental loop. The results of the calculations and the experiments are in good agreement. Nonlinear density wave oscillations were analyzed using the RETRAN-02 code. The theory of nonequilibrium thermodynamics was used to find an explicit criterion to estimate the threshold of the stability. Experimental simulation of the nuclear feedback density wave instability was also carried out in a test loop using. computer controlled electric power.
