... the threshold gravitational head height at which there will be subcooled liquid at the condenser exit, indicating that it can be used as a predictive tool for identifying the optimal loop charge for a given heat load. Keywords: Gravity driven two-phase loop thermosyphon, pressure drop, refrigerant charge mass...

... for bubbles, thus suppressing the reversal flow of the bubbles. Compared with ISM, SSM could break out the long slug bubbles more effectively and prevent gigantic bubbles from forming. The two-phase pressure drop in SSM could be reduced by 23% on average compared with ISM. This work is trying to provide...

... heat sink fillet profile temperature distribution pressure drop Proceedings of the ASME 2021 Heat Transfer Summer Conference HT2021 June 16-18, 2021, Virtual, Online HT2021-61091 THE EFFECT OF FILLET PROFILE ON HEAT TRANSFER CHARACTERISTICS OF HEAT SINK Karim Egab Saad K. Oudah Azzam S...

... was v velocity in the y-direction (m/s) conducted. The effect of the sine wave frequency, the pin fins' w velocity in the z-direction (m/s) diameter, and the hydraulic diameter of the microchannel are studied. The results are quantified in terms of thermal resistance GREEK ALPHABETS and pressure drop...

... Engineering Department *National Water and Energy Center United Arab Emirates University Al Ain, Abu Dhabi, UAE ABSTRACT Re Reynolds number This article discusses the mathematical modeling of a P pressure drop (Pa) T temperature (K) straight microchannel heat sink, embedded with pin-fins, for u velocity...

...CONDENSATION HEAT TRANSFER AND PRESSURE DROP OF R134A IN HORIZONTAL MICRO-SCALE ENHANCED TUBE Zongbao Gu, Xiang Ma, Yan He*,Lianxiang Ma Department of Mechanical and Electrical Engineering, Qingdao University of Science and Technology Qingdao, Shandong, China Wei Li Department of Energy Engineering...

.... Wilson diagram method was used to determine the enhancement ratio of the water side heat transfer coefficient of EHT3 tube. It was found that the pressure drop increased with the increase of mass flux, while the heat transfer coefficient showed different trends, and the smooth tube was always the lowest...

... to explore the behavior and performance of this kind of fin, showing that the hydraulic performance is well represented by correlations widely used in literature, while thermal performance seems to be under predicted. Keywords: Fluid flow and heat transfer; Trapezoidal, CFD, Reynolds, Pressure Drop. 1...

... excessive pressure drops associated with full width twisted tape elements. The numerical analyses were performed with various free space ratios ( S = 0.0, 1.0, and 2.0) at a constant twist ratio ( TR ) of 5. Uniform heat flux was applied to the external surface of the tube and Reynolds numbers varied from...

... 1 Copyright © 2012 by ASME CONDENSATION PRESSURE DROP AND HEAT TRANSFER IN 5-MM-OD MICRO-FIN TUBES Wei Li1 Dan Huang1, Zan Wu1, Hong-Xia Li1, Zhao-Yan Zhang2, Rong-Hua Hong1, Si-Pu Guo1, Jing Li1 1.Zhejiang University, Department of Energy Engineering, Hangzhou, Zhejiang 310027, PR China 2...

... by the inlet conditions. gas-liquid two-phase flow microchannel inlet geometry flow pattern pressure drop heat transfer 1 Copyright © 2007 by ASME Proceedings of HT2007 2007 ASME-JSME Thermal Engineering Summer Heat Transfer Conference July 8-12, 2007, Vancouver, British Columbia, CANADA HT2007...

.... It is found that both the heat transfer coefficient and the pressure drop for the shell-side are in good arrangement with experimental results. Comparing with circular-tube heat exchangers, the simulation result shows that the pressure drop of flat-tube heat exchangers decreases 12%∼20%, and the coefficient...

... is obtained for S/D = 0.75. heat transfer enhancement rib inserted tube pressure drop performance comparison Proceedings of HT08 2008 ASME Summer Heat Transfer Conference August 10-14, 2008, Jacksonville, FL. USA N numerical method. The variation of Nusselt number, friction factor and triangular...

... the velocity and pressure drop for partially-confined heat sinks has been successfully developed. The air velocities flowing into heat sink U s through side bypass U 1 and top bypass U 2 for various 0.47<H/H c <1 ratios are evaluated, where H/H c is the ratio of the heat sink height to channel height...

... 03 04 2009 The use of streamlined tubes to reduce pressure drop across polymer tube bundles is considered because of the relative ease of fabrication. The drag and convective heat transfer coefficients along the outer surface of lenticular and elliptical tubes with minor-to-major axis...

... 03 04 2009 Present authors have measured heat transfer coefficients (Cavallini et al. [1, 2]) and pressure drops (Cavallini et al. [3, 4]) during condensation of R134a, R410A and R236ea inside a flat multiport mini-channel tube with a 1.4 mm hydraulic diameter. The experimental heat...

... 03 04 2009 The main purpose of this paper was to experimentally study the heat transfer and pressure drop characteristics of refrigerant R134a boiling inside a new geometry microfin helically coiled tube. Experiments were performed in a range of mass quality from 0.05 up to 0.9, mass...

... 03 04 2009 In this work a uniquely designed air-water bubbly flow heat transfer experiment is accomplished to investigate the characteristics of pressure drop of airflow and heat transfer between water and tubes for its potential application in evaporative cooling. The attempts...

... 18 12 2008 Uniquely shaped tubes extruded with an inner circular flow passage and an outer streamlined profile are proposed to withstand the inside fluid pressure and simultaneously to reduce the pressure drop across heat exchanger tube bundles comprising hundreds of small-diameter...