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This paper quantifies experimentally the effect of ventilation in diesel pool fire (d = 0.6 m) in a cubical compartment of 64 m3 with ventilation opening factor in range of 0.088–2.828 m 5 / 2 . The work is addressed to fire safety in nuclear power plant in which ventilated enclosure are frequently used for chemical processing of flammable fuels. In present work, fuel mass loss rate, global CO concentration, global CO/CO2 yield, flame temperature, global equivalence ratio, doorway temperature with velocity profile, and heat flux are measured to predict the effect of ventilation in compartment fire. Ventilation with test 3 is noted as critical opening i.e. after that mass loss rate suddenly decreased. It is also observed that compartment fire is affected more by varying door height rather than varying door width. Unpredictably, global CO emission are obtained nearly the same regardless of doorway opening. Combustion efficiency is found to be in range of 0.39–0.93. Results showed that reduction in ventilation results in oscillating flame behavior and increase in upper layer gas temperature. Present data correlated well under thermal scaling analysis. The results shown in present work can be used as an input to fire hazard analysis in nuclear power plants. [ABSTRACT FROM AUTHOR]

A reliable, pre-harvest, crop yield prediction based on meteorological factors is important to anticipate adverse effect of weather variables. Discriminant score-based regression models, MLP artificial neural network (ANN) models, and regression-ANN hybrid models were used to model potato (Solanum tuberosum L.) yield. Maximum and minimum temperatures, rainfall, and relative humidity, and their indices, were used to obtain discriminant scores for each year. These discriminant scores, along with a time variable, were used as inputs and potato yield as outputs for the development of models. A hybrid model consisting of linear and non-linear components performed better than individual models if combined linearity and nonlinearity are present in the data, else the ANN models were better than regression models. The best models can be used to obtain a reliable forecast of potato yield at 6–8 weeks before harvest using meteorological data. [ABSTRACT FROM AUTHOR]

Summary: In this study, experiments were performed in a 4 m × 4 m × 4 m compartment having a door size of 2 m × 1 m in the front wall. The pan diameter has been varied from 0.2 to 1.0 m in order to evaluate parameters, such as mass loss rate, CO/CO2 yield, global equivalence ratio (GER), flame height, flame pulsation frequency and total heat flux within the compartment. Experimental mass loss flux was found to be 0.23 times lesser than the mass loss flux obtained with an open fire test. A correlation was developed to estimate the flame height for compartment fire as the function of pool diameter and heat release rate. Pulsation frequency has been well correlated with previous studies for smaller pool sizes, due to no interaction between the flame tip and upper smoke layer. However, for a larger pool, this seems to be deviated due to a larger smoke layer thickness. Heat flux variations were observed to follow power law trends for all the inner surfaces of the compartment with respect to pool diameters. This investigation is also essential for better understanding of diesel (sooty) fuel burning effects with respect to pool size in a compartment having well‐ventilated door opening. [ABSTRACT FROM AUTHOR]

Radiative heat transfer between the different components of the nuclear reactor channel (fuel pins, pressure tube (PT) and calandria tube (CT)) is the predominant mechanism of heat transfer in a channel when coolant flow is ceased. In this paper, the thermal behavior of the channel of Indian PHWR that has thirty-seven fuel elements is analyzed for a postulated accident such as loss of coolant accident (LOCA) coupled with the failure of the emergency core cooling system. (ECCS). The analysis has been performed using experimental, numerical and analytical techniques. The experiment is performed under the pseudo-steady-state condition, and the temperature profiles for the different parts of a simulated channel are obtained. The numerical analysis of the above problem is carried out using the ANSYS® Fluent 19.0. The code calculation is compared with the exact solution which is obtained using the radiosity network method. There is a reasonably good agreement between these three types of analysis. The results from these analyzes show that the temperature gradient (along the radial direction) is developed in the fuel bundle simulator (FBS) from the center fuel element to the outer ring fuel element. Also, an insignificant circumferential temperature gradient is observed in the FBS, PT and CT. [ABSTRACT FROM AUTHOR]