scholarly journals Experiment data report for semiscale MOD-1 tests S-03-A, S-03-B, S-03-C, and S-03-D (reflood heat transfer tests). [PWR]

1976 ◽  
Author(s):  
Author(s):  
Yantao Li ◽  
Yulong Ji ◽  
Katsuya Fukuda ◽  
Qiusheng Liu ◽  
Hongbin Ma

Abstract In this paper, the forced convective heat transfer of FC-72 was experimentally investigated for various of parameters like velocity, inlet temperature, tube size, and exponential period of heat generation rate. Circular tubes with different inner diameters (1, 1.8 and 2.8 mm) and heated lengths (30–50 mm) were used in this study. The experiment data suggest that the single-phase heat transfer coefficient increases with increasing flow velocity as well as decreasing tube diameter and ratio of heated length to inner diameter. The experiment data were nondimensionalized to study the effect of Reynolds number (Red) on forced convection heat transfer. The results indicate that the relation between Nusselt numbers (Nud) and Red for d = 2.8 mm show the same trend as the conventional correlations. However, the Nud for d = 1 and 1. 8 mm depend on Red in a different manner. The conventional heat transfer correlations are not adequate for prediction of forced convective heat transfer in mini channels. The heat transfer correlations for FC-72 in vertical small tubes with diameters of 1, 1.8 and 2.8 mm were developed separately based on the experiment data. The differences between experimental and predicted Nud are within ±15%.


2018 ◽  
pp. 61-70
Author(s):  
Ewa Szymanek

This paper is devoted to experimental and numerical studies of heat distribution in an external building bulkhead. It analyzes the variation of temperature across the width of the bulkheads including the impact of changing external conditions. Mathematical model used in the research is formulated based on a fractional differential equation, which was proven to be a useful tool for describing this type of process in previous paper. Numerical results are compared with experiment data for different bulkhead configurations.


Author(s):  
Fadi Alnaimat ◽  
Omar Alhammadi ◽  
Bobby Mathew

Abstract The main objective of this work is to develop a numerical model to analyze heat transfer and condensation of a rising spherical bubble. The model included the bubble shrinkage during condensation, which can be utilized to analyze the bubble’s total energy loss, raising velocity, and condensation rate of a single bubble compared to multiple bubbles with the same total thermal energy. The equations of motion, heat, and mass transfer were developed. The model results were verified with the bubble condensation experiment data in the literature, in which they exhibited a good agreement. For the validation, the model results were compared with bubble condensation experiment data in the literature, which showed a good agreement with the experimental results. The dynamic term of the model is developed using the force balance on a gravity-driven bubble, including hydrodynamic drag force and gravity/buoyancy force, which acting with and against the bubble’s motion direction. For the thermal part of the model, a condensation correlation has been adapted to represent the Nusselt number as a function of Reynolds number (Re), Jakob number (Ja), and Prandtl number (Pr). A MATLAB code is developed in order to calculate the instantaneous velocity, the radius, and the mass loss of the vapor bubble in each time step. Moreover, the fundamental behavior for a single bubble and multiple bubbles was investigated in various initial conditions under the same total thermal energy. The effects of the initial bubble radius and the temperature difference between the liquid and vapor phases were analyzed for both scenarios in order to examine the condensation rate. It was found that the thermal behavior of the condensing bubble can be improved by forcing the bubble to collapse into sub bubbles, which will increase the total interfacial area and the rising velocity. Farther, due to generated sub bubbles, the resultant velocity increased the turbulency and the heat transfer rate accordingly. This study can lead to improve the heat transfer rate and allow for more intensive research to enhance the condensation rate.


Author(s):  
Jiange Liu ◽  
Minjun Peng

The physical phenomenon of the flow and heat transfer characteristic in vertical narrow annulus channel is a little different from general channel. It is valuable to improve the model veracity for exactly predicting the nuclear power system key physical phenomenon. The heat transfer characteristic of two narrow annulus channels (narrow gap 1.0mm and 1.5mm) is analyzed by means of the RELAPSCDAPSIM/MOD3.4 code recently developed by SDTP. Compared with related experiment data, the results show that the new developed code could predict key parameters such as fluid temperature, wall temperature, heat transfer coefficient, pressure drop, the occurrence condition of the flow instability and so on. The code has the ability to simulate the narrow annulus channel heat transfer characteristic.


2012 ◽  
Vol 499 ◽  
pp. 91-95
Author(s):  
Zi Guang Rong ◽  
Z.J. Wu ◽  
P.F. Feng ◽  
D.W. Yu

This paper provides heat transfer modeling analysis and parameter optimization for wafer system of laser annealing equipment. Heat transfer models are established at axial and radial directions. With the help of programming calculation, the relation between heat flux of radiation and distance of adjacent layers can be analyzed. In order to minimize heat transfer interference on the motor system, optimized parameters are selected. Performance of certain selection is verified by FEA simulation and experiment data.


Volume 3 ◽  
2004 ◽  
Author(s):  
Xuelei Chen ◽  
Mauricio A. Sa´nchez ◽  
William H. Sutton

This investigation is part of the composite fuel project in the University of Oklahoma [1]. The composite fuel is a mixture resulted from natural gas resolving in liquid propane, which has a relatively lower storage pressure compared with that of compressed natural gas. Here in this paper, a numerical investigation of conjugate heat transfer among convection, wall conduction and flow boiling in a double-pipe heat exchanger is presented. The heat exchanger has hot fluid flowing in the annular section and propane boiling in the inside tube. A computer program is developed to calculate the conjugate heat transfer of convection, conduction and boiling. In computing the convection and conduction, control volume method and SIMPLE algorithm are used to solve momentum equations and the energy equation of conjugate heat transfer. The contribution of this work is to combine the third kind (Neuman) of boundary condition with the boiling correlations for flow boiling in horizontal tubes in order to calculate the conjugate heat transfer of the whole problem. Two boiling correlations have been selected to give inside tube boiling heat transfer coefficient. Because the boiling coefficient depends on the wall temperature and local propane quality, so we have to solve the boiling correlation, the conduction and the convection governing equations simultaneously. The iteration method and TDMA are used to solve these coupled equations. The two boiling correlations are Chen’s (1966) correlation [2] and Kandlikar’s (1990) correlation [3]. Finally the results are compared with the experiment data. It has been found in low quality range, Kandlikar’s result is close to the experiment data. Because very few data of propane flow boiling can be found in literature, we use propane pool boiling data by Shen, Spindler and Hahne (1997) [4] to estimate parameter Ffl in Kandlikar’s correlation. The influence of simultaneously developing velocity and temperature field at entrance length in annular passage is considered and discussed in detail. The wall conduction resistance is also compared with convection and boiling resistance in the whole length of the heat exchanger. The completed computer program can be used to the design of shell and tube heat exchangers.


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