Mirmanto Mirmanto^a,*, Syahrul Syahrul^a, Agung Tri Wijayanta^b

Frontiers in Heat and Mass Transfer, Vol.20, pp. 1-5, 2023, DOI:10.5098/hmt.20.9

Abstract A study to examine the effect of evaporator diameters on the performances of a custom air-water generator had been conducted in naturally room air temperatures. Performances in this study consisted of fresh water production, coefficient of performance, and total heat transfer from the air. The freshwater was attained from the dew that dropped from the evaporator walls. It was from water vapour in the air that condensed due to the low temperature of the evaporator walls. The evaporator which had dimensions of 285 mm x 12.7 mm x 480 mm was placed in an open More >

Ameer Abed Jaddoa^* , Hussain Saad Abd

Frontiers in Heat and Mass Transfer, Vol.20, pp. 1-12, 2023, DOI:10.5098/hmt.20.6

Abstract In this work, the demeanour of heat transfer in a cooled upstanding turbulent flow condition of supercritical carbon dioxide SC- CO2 was investigated and analyzed. Several scenarios were adopted to handle the experimental data acquired by applying a perpendicular pipe with bending tape used in the examination model. The outcomes were presented using a typical method 'the dimensionless constitution'. Also, a modification was achieved to improve the relationship among the parameters for the processes of up and down flows. The achieved results will help address this research gap on turbulent perpendicular compound heat load based More >

Ningbo Guo, Xianming Gao^*, Duanling Li, Jixing Zhang, Penghui Yin, Mengyi Hua

CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.3, pp. 3061-3082, 2023, DOI:10.32604/cmes.2023.026657 - 09 March 2023

Abstract Computational fluid dynamics was used and a numerical simulation analysis of boiling heat transfer in microchannels with three depths and three cross-sectional profiles was conducted. The heat transfer coefficient and bubble generation process of three microchannel structures with a width of 80 μm and a depth of 40, 60, and 80 μm were compared during the boiling process, and the factors influencing bubble generation were studied. A visual test bench was built, and test substrates of different sizes were prepared using a micro-nano laser. During the test, the behavior characteristics of the bubbles on the More >

M’Barka Mourabit^1,*, Meryam Meknassi², Soukaina Fekkar¹, Soumia Mordane¹, Hicham Rouijaa³, El Alami Semma⁴

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.7, pp. 1753-1774, 2023, DOI:10.32604/fdmp.2023.025739 - 08 March 2023

Abstract

The effect of the tilt angle on mixed convection and related heat transfer in a “T” shaped double enclosure with four heated obstacles on the bottom surface is numerically investigated. The considered obstacles are constantly kept at a relatively high (fixed) temperature, while the cavity’s upper wall is cooled. The finite volume approach is used to solve the mass, momentum, and energy equations with the SIMPLEC algorithm being exploited to deal with the pressure-velocity coupling. Emphasis is put on the influence of the tilt angle on the solution symmetry, flow structure, and heat exchange through the

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Romana Basit¹, Xinyang Li¹, Zheqing Huang¹, Qiang Zhou^1,2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.2, pp. 1509-1526, 2023, DOI:10.32604/cmes.2023.025308 - 06 February 2023

Abstract Direct Numerical Simulations have been carried out to study the forced convection heat transfer of flow through fixed prolate particles for a variety of aspect ratios ar = {5/4, 5/3, 5/1} with Reynolds number (Re) up to 100. Three variations of the solid volume fraction c = {0.1, 0.2, 0.3} with four Hermans orientation factors S = {−0.5, 0, 0.5, 1} are studied. It has been found that changes in S cause prominent variations in the Nusselt number. In general, Nusselt number increases with the decrease of S. For all three aspect ratios, the Nusselt number remains More > Graphic Abstract

Daoming Shen^1,*, Jinhong Xia¹, Chao Gui¹, Songtao Xue²

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1411-1424, 2023, DOI:10.32604/fdmp.2023.024924 - 30 January 2023

Abstract The thermal transmission coefficient for a micro-ribbed tube has been determined using theoretical relationships and the outcomes of such calculations have been compared with experiments conducted using a R1234yf refrigerant undergoing condensation. In particular four theoretical single-phase flow and three multi-phase flow models have been used in this regard. The experimental results show that: the Oliver et al. criterion equation overestimates the experimental results as its accuracy is significantly affected by the specific conditions realized inside micro-fin tubes; the Miyara et al. criterion equation prediction error is less than 15%; the Cavallini et al. approach More >

Toufik Sahabi^1,*, Smain Balaska²

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.4, pp. 977-990, 2023, DOI:10.32604/fdmp.2022.022059 - 02 November 2022

Abstract The heat transfer equation is used to determine the heat flow by conduction through a composite material along the real axis. An analytical dimensionless analysis is implemented in the framework of a separation of variables method (SVM). This approach leads to an Eigenvalues problem that is solved by the Newton’s method. Two types of dynamics are found: An unsteady condition (in the form of jumps or drops in temperatures depending on the considered case), and a permanent equilibrium (tending to the ambient temperature). The validity and effectiveness of the proposed approach for any number of More > Graphic Abstract

Shrikant Arunrao Thote^*, Netra Pal Singh

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.3, pp. 711-722, 2023, DOI:10.32604/fdmp.2022.021651 - 29 September 2022

Abstract The thermo-hydraulic properties of circular tubes with a twisted tape inside (used accordingly to induce turbulence and enhance heat transfer through the tube wall) are described for Reynolds Numbers ranging from 830 to 1990. Tapes twisted with the three distinct twist ratios are considered, namely, 6, 4.4 and 3. Air is used as the working fluid in several tests. For the sake of comparison, the standard tube with no insert is also examined. It is shown that in the presence of the twisted tape, the ‘frictional factor’, ‘Nusselt Number’ and the ‘thermal performance factor’ are More >

Mohammad Saraireh^*

Intelligent Automation & Soft Computing, Vol.36, No.1, pp. 57-70, 2023, DOI:10.32604/iasc.2023.032050 - 29 September 2022

Abstract With the growing global energy and environmental problems, electric vehicles that are both environmentally friendly and cost effective have seen rapid growth. An electrified vehicle’s effective thermal management must include all of the vehicle’s systems. However, optimizing the thermal behavior of each component is insufficient. A lithium-ion battery’s operating temperature has a significant impact on its performance. When working at low temperatures, the internal resistance of lithium-ion batteries increases, the available energy and power of the system decreases, and lithium precipitation caused by low-temperature charging may cause safety issues; high-temperature operation and temperature inconsistency between… More >

Mehdi Moslemi¹, Motahare Mahmoodnezhad¹, S. A. Edalatpanah^1,*, Sulima Ahmed Mohammed Zubair², Hamiden Abd El-Wahed Khalifa^2,3

CMES-Computer Modeling in Engineering & Sciences, Vol.134, No.3, pp. 1957-1973, 2023, DOI:10.32604/cmes.2022.021481 - 20 September 2022

Abstract In this research, a numerical study of mixed convection of non-Newtonian fluid and magnetic field effect along a vertical wavy surface was investigated. A simple coordinate transformation to transform wavy surface to a flat surface is employed. A cubic spline collocation numerical method is employed to analyze transformed equations. The effect of various parameters such as Reynolds number, volume fraction 0-, Hartmann number, and amplitude of wave length was evaluated in improving the performance of a wavy microchannel. According to the presented results, the sinusoidal shape of the microchannel has a direct impact on heat More >