Reactor Inlet Temperature Research Articles

Parametric sensitivity and runaway in tubular reactors

AbstractParametric sensitivity of tubular reactors is analyzed to provide critical values of the heat of reaction and heat transfer parameters defining runaway and stable operations for all positive‐order exothermic reactions with finite activation energies, and for all reactor inlet temperatures. Evaluation of the critical values does not involve any trial and error.

Reactor noise analysis of the experimental fast reactor JOYO

Experimental fast reactor JOYO achieved its first criticality in 1977 spring. Since then a series of reactor noise analysis has been carried out. During zero power testing, the reactor kinetic parameters, i.e. β/l and subcriticality, were obtained, applying band-pass filter and polarity correlation methods. As the high power operation started from 1978, the reactor noise analysis based on neutron flux spectra has been proceeded. This paper presents study of noise analysis for rather lower frequency region at high power operation. At 50 Mwt power level operation, noises of neutron flux signals, reactor inlet temperatures and subassembly outlet temperatures were measured, and then auto power spectral densities and coherence functions were calculated. The frequency range for the noise analysis is for 10 −3 − 10 −1 Hz. In the APSD of neutron flux, a low peak was observed at 2.5×10 −2 Hz. For neutron noise, it was estimated that the noises in the frequency region lower than 1.5 × 10 −2 Hz is a core inherent temperature noises, while that in the frequency region higher than 1.5 × 10 −2 Hz is a core inherent neutron noise. The coherence function of neutron fluxes, which are signals of ex-core detectors located at opposite positions against the core center, indicated that some space dependent phenomena of neutron noise might exist in 5×10 −3 − 6×10 −2 Hz. The space dependency in 5×10 −3 − 1.5×10 −2 Hz were estimated to be produced by the sodium temperature noise due to the insufficient mixing of two primary coolant loops. In 1.5×10 −2 − 6×10 −2 Hz, the peak existed at 2.5×10 −2 Hz and reverse phases were observed in the coherence of two neutron signals at opposite side of the core. With the investigation of phase relations between neutron flux and subassembly outlet temperature in this frequency region, the phenomenon was estimated to be due to mechanical vibration of some reactor core components. When the static gain of reactivity-to-power transfer function increased, the changes of reactor noise characteristics were observed. Since the change of the gain indicates a change of the reactor core characteristics, the observation of reactor noise characteristics has a potential for the surveillance of the reactor core.

Measurement of subassembly outlet coolant temperature in the JOYO experimental fast reactor

Abstract Thermocouple temperature sensors are installed above the central region of the core in the JOYO experimental fast reactor to monitor the outlet coolant temperature of 115 subassemblies. This paper summarizes the experimental temperature data obtained during initial 50 MWt operation of the reactor. Subassembly outlet coolant temperature distributions that were obtained under various power levels, different main cooling system flowrates, and unequal reactor inlet temperatures from the two cooling loops are described. In addition, coolant temperature and flowrate distributions at the subassembly outlet measured in a zero power experiment are presented.

Evaluation of catalysts for vapor phase oxidation of odorous organic compounds

An integral flow reactor was used to evaluate the odor reducing capabilities of four commercially available catalysts consisting of 0.5% platinum, 0.1% platinum, 0.5% palladium and 10% copper oxide supported on γ-alumina. Oxidation of four organic odorants, n- butanol, n- butyraldehyde , n- butyric acid and toluene was carried out at reactor inlet temperatures ranging from 116°C to 497°C, for space velocities of 50000, 80000 and 100000 h −1. Conversion of the odorants was determined with a gas Chromatograph equipped with a flame ionization detector. Odor levels were determined according to the ASTM dilution method. The platinum catalysts were found to be more effective in terms of chemical conversion as well as odor removal efficiency. The palladium and copper oxide catalysts required much higher temperatures than the platinum catalysts for comparable performance. The ease of oxidation of the odorous compounds depended on the type of catalyst. Both the palladium and copper oxide catalysts appeared to promote reactions that led to the formation of odorous partial oxidation products, but this was not apparent with the platinum catalysts.

Abstracts of contributed papers for annual meeting Professional Group on Nuclear Science October 6 and 7, 1954

The problem of designing a constant reactor outlet temperature control system for a thermal reactor power plant is considered. The dynamic control characteristics of the power plant are described in terns of (1) the response of reactivity to variations of reactor inlet coolant temperature, (2) the heat transfer characteristics of the reactor and boiler, and (3) the time lags of the reactor coolant loop. It is shown how the inherent characteristics of the power plant may be used to advantage by constant reactor outlet temperature control systems employing the reactor inlet and outlet temperatures as control variables. An important feature of these control systems is the computation of the reactor inlet temperature from the boiler outlet temperature or the steam plant variables using recently developed transport delay circuits to compensate for the boilerto-reactor coolant transport delay.