Helium is utilized as coolant in high temperature gas cooled reactors. Rectangular narrow slit channels are commonly present in the core. The flow and heat transfer properties of helium significantly affect the core t...
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The fluoride-salt-cooled high-temperature advanced reactor (FuSTAR) is an advanced small modular reactor, which aims to the electric supplement and clean heat production to western China. In this study, neutronics and...
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Heat dissipation is a significant factor limiting the advancement of electronics. Currently, air cooling remains the most widely used method for heat dissipation due to the advantages of low-cost and easy-maintenance....
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The ejector is a promising hydrogen recirculation device in proton exchange membrane fuel cell (PEMFC) systems. However, the limited entrainment performance of the ejector at wide operating conditions hinders its deve...
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To investigate the combustion phenomenon of aluminum droplets within propellants, this study amalgamates the evaporation combustion process of aluminum droplets with the AP/HTPB (Ammonium perchlorate/Hydroxyl-terminat...
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MXene materials have exhibited potential in electrochemistry, particularly in gas sensing, due to their excellent conductivity, large specific surface area of layered materials, and unique functional groups. However, ...
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An accurate prediction of the critical gas velocity for the liquid loading is of great importance for operators to select the tubing diameter for the newly drilled gas wells,or to optimize the production rate for prod...
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An accurate prediction of the critical gas velocity for the liquid loading is of great importance for operators to select the tubing diameter for the newly drilled gas wells,or to optimize the production rate for production *** is clear from previous experimental studies of the liquid entrainment rate in the gas core that the liquid is mainly carried in the form of film under the critical condition of the liquid loading *** is more reasonable to establish a mathematical model based on the film reversal rather than based on the droplet *** our previous paper entitled“Prediction of the critical gas velocity of liquid unloading in the horizontal gas well”,a new analytical model was established based on the force balance between the gas-liquid interfacial friction force and the bottom film gravity,but the model is not very convenient to use because of the complexity of calculating the average film *** the present study,a new method is proposed to calculate the average film thickness from the bubble drift velocity in the mixture,so the new analytical model becomes much easier to *** new analytical model is evaluated against 103 sets of experimental data,the data in 124 vertical gas wells and one horizontal gas ***,the effect ofthe liquid loading on the production of the horizontal gas well is also analyzed.
With the continuous development of chip integration and information technology, the heat dissipation has become a major limitation on the performance of electronic devices such as 5G base station, data center and so o...
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With the continuous development of chip integration and information technology, the heat dissipation has become a major limitation on the performance of electronic devices such as 5G base station, data center and so on, and meanwhile a challenge of conventional single-phase convection cooling methods. Boiling is prospective in high heat flux cooling and energy saving due to the usage of latent heat. R1233zd(E), an environmentally friendly refrigerant (GWP=1, ODP=0) with a freezing point of -107°C, is a potential working fluid in phase-change heat sinks for geographical applications. Nevertheless, the poor boiling performance of R1233zd(E) on plain surface due to the limitation in thermophysical properties must be enhanced. Moreover, conventional heat sinks are mostly copper-based, which are inconvenient for transportation and installation, and costly for production as well. In this work, micro pin fins in the range of 100-500 μm are fabricated on the aluminum surface to enhance the pool boiling of R1233zd(E). Moreover, the influence of their size and saturation pressure on the bubble behavior, critical heat flux (CHF) and heat transfer coefficient (HTC) is experimentally and theoretically investigated. The results show that the increase of pressure, as well as the ensuing various nucleation site and capillary effect to rewet the evaporation region, can lead to an increase in the CHF and HTC. Notably, the 150-200 μm micro pin-finned surfaces reaches the highest CHF and 100 μm one owns the highest HTC, which is 214% and 383% higher than that of plain surface, respectively. BY considering the balance of capillary effect and bubble convolution effect, a model of CHF is proposed to reveal the mechanism of optimum size of the micro pin fins. The predicted CHFs have an inaccuracy of less than ±20% comparing to experimental values. This paper makes up for the lack of basic experimental data on pool boiling of R1233zd(E) on aluminum surface, which thus provides guidance for
The two-step supercritical water desorption-gasification (TSSCWDG) technology can significantly improve the gasification efficiency of oil sludge. However, few works have been conducted to explore the influence of ope...
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The rapid development in performance, integration and miniaturization of electronics and other high power devices cause huge heat flux values. However, transitional cooling methods can hardly meet the requirement of d...
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