A stochastic local limited one-dimensional rice-pile model is numerically investigated. The distributions for avalanche sizes have a clear power-law behavior and it displays a simple finite size scaling. We obtain the...A stochastic local limited one-dimensional rice-pile model is numerically investigated. The distributions for avalanche sizes have a clear power-law behavior and it displays a simple finite size scaling. We obtain the avalanche exponents Ts= 1.54±0.10,βs = 2.17±0.10 and TT = 1.80±0.10, βT =1.46 ± 0.10. This self-organized critical model belongs to the same universality class with the Oslo rice-pile model studied by K. Christensen et al. [Phys. Rev. Lett. 77 （1996） 107], a rice-pile model studied by L.A.N. Amaral et al. [Phys. Rev. E 54 （1996） 4512], and a simple deterministic self-organized critical model studied by M.S. Vieira [Phys. Rev. E 61 （2000） 6056].展开更多
Before rise-to-power tests, the actual measured value of heat released from the Reactor Pressure Vessel(RPV) or removed by the Vessel Cooling System(VCS) cannot be obtained. It is difficult for operators to evaluate t...Before rise-to-power tests, the actual measured value of heat released from the Reactor Pressure Vessel(RPV) or removed by the Vessel Cooling System(VCS) cannot be obtained. It is difficult for operators to evaluate the reactor outlet coolant temperature supplied from the High Temperature Engineering Test Reactor(HTTR) before rise-to-power tests. Therefore, when the actual measured value of heat released from the RPV or removed by the VCS are changed during rise-to-power tests, operators need to evaluate quickly, within a few minutes, the heat removed by the VCS and the reactor outlet coolant temperature of 30 MW, at 100% reactor power, before the temperature achieves 967℃ which is the maximum temperature limit generating the reactor scram. In this paper, a rapid evaluation method for use by operators is presented. The difference between the experimental and analytical results was within 30(k W) and it is appropriate that the presented evaluation method can be applied; therefore, operators can analyze the heat removed by the VCS quickly, within a few minutes, before and during Rise-to-Power Tests.展开更多
基金supported by the Science Foundation of Henan University of Science and Technology under Grant Nos.05-032 and 2006QN033
文摘A stochastic local limited one-dimensional rice-pile model is numerically investigated. The distributions for avalanche sizes have a clear power-law behavior and it displays a simple finite size scaling. We obtain the avalanche exponents Ts= 1.54±0.10,βs = 2.17±0.10 and TT = 1.80±0.10, βT =1.46 ± 0.10. This self-organized critical model belongs to the same universality class with the Oslo rice-pile model studied by K. Christensen et al. [Phys. Rev. Lett. 77 （1996） 107], a rice-pile model studied by L.A.N. Amaral et al. [Phys. Rev. E 54 （1996） 4512], and a simple deterministic self-organized critical model studied by M.S. Vieira [Phys. Rev. E 61 （2000） 6056].
文摘Before rise-to-power tests, the actual measured value of heat released from the Reactor Pressure Vessel(RPV) or removed by the Vessel Cooling System(VCS) cannot be obtained. It is difficult for operators to evaluate the reactor outlet coolant temperature supplied from the High Temperature Engineering Test Reactor(HTTR) before rise-to-power tests. Therefore, when the actual measured value of heat released from the RPV or removed by the VCS are changed during rise-to-power tests, operators need to evaluate quickly, within a few minutes, the heat removed by the VCS and the reactor outlet coolant temperature of 30 MW, at 100% reactor power, before the temperature achieves 967℃ which is the maximum temperature limit generating the reactor scram. In this paper, a rapid evaluation method for use by operators is presented. The difference between the experimental and analytical results was within 30(k W) and it is appropriate that the presented evaluation method can be applied; therefore, operators can analyze the heat removed by the VCS quickly, within a few minutes, before and during Rise-to-Power Tests.
