Theoretical analysis on condensation heat transfer on microstructured hybrid hydrophobic-hydrophilic tube

Aminian, Ehsan; Kamali, Mohammad; Vatanjoo, Ehsan; Saffari, Hamid

doi:10.1007/s00231-021-03170-2

Cited by 9 publications

(6 citation statements)

References 33 publications

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“…Vatanjoo et al 27 have also provided useful insights on the heat transfer on the hydrophobic–hydrophilic hybrid surfaces. Aminian et al 28 and Saffari et al 29 have theoretically investigated the microstructured hybrid surface heat transfer characteristics with Marangoni convection effect and hydrophobic-hydrophilic tube respectively. Babaei et al 30 have worked on the numerical analysis of heat transfer and pressure drop of nanofluids in a combined porous media of hydrophobic and hydrophilic surfaces.…”

Section: Introductionmentioning

confidence: 99%

A numerical study on effect of intra and inter spaced winding configuration on performance of oil forced transformer cooling system

Muralikrishna,

Satyanarayana Reddy,

Sahu

et al. 2024

Proceedings of the Institution of Mechanical Engineers, Part A:

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The present work aims at investigating, numerically, the heat transfer characteristics of transformer cooling system under forced circulation for three different winding configurations. The purpose of a transformer cooling system is to keep the hot spot temperature within the critical value for a long life of transformer, which increases with enhanced cooling of transformer windings. Thus, two different winding configurations are modeled by providing space within the windings (an intra-space model) and in between the windings (an inter-space model) to improve the fluid-solid interaction. A conventional winding, without spacing, is also modeled for comparative study. A 315 kVA, 3-phase core type transformer is taken as the base model from which the winding and core specifications are obtained analytically. Parameters chosen to measure the influence of winding configuration are local temperature distribution in the windings and core and maximum transformer temperature. Results are obtained for all three models with varying space for various cooling mediums like naphthenic oil, silicon oil, and synthetic ester oil at flow velocities ranging from 0.72 m/s to 2.16 m/s. It is observed that the gap between the windings, interspacing, decreases the secondary winding temperatures, while it increases the core and primary winding temperatures. However, the intra spacing configuration finds a drop in local temperatures at all locations of the transformer windings and core. The enhanced heat dissipation to the cooling agent, with intra spacing winding configuration, reduces the maximum transformer temperature. Contrasting to the above, the inter-space model has an adverse effect on maximum temperature at all widths of space considered. Quantitatively, the space within the transformer reduces the maximum temperature by 5% in comparison with the space between the windings. The increased velocity of the cooling medium, Naphthenic oil, from 0.72 m/s to 2.16 m/s reduces the maximum temperature by 4.5 units. The study made to know the role of cooling medium discloses that the synthetic ester oil shows better performance for reducing temperature values due to its highly viscous nature.

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Section: Introductionmentioning

confidence: 99%

A numerical study on effect of intra and inter spaced winding configuration on performance of oil forced transformer cooling system

Muralikrishna,

Satyanarayana Reddy,

Sahu

et al. 2024

Proceedings of the Institution of Mechanical Engineers, Part A:

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“…Important marine structures, marine equipment, and sea bridges have contributed to economic development as well as scientific and technological advancement [1][2][3][4][5]. As part of these efforts, marine equipment assists people in exploring the ocean's resources, including both physical and chemical resources [6][7][8][9]; sea bridges facilitate coastal transportation and promote regional development, etc. Due to the increasing number of navigable ships and various complex environmental factors, there has been an increase in the risk of ship-bridge collisions and ship-marine equipment collisions.…”

Section: Introductionmentioning

confidence: 99%

A Review of Artificial Intelligence-Based Optimization Applications in Traditional Active Maritime Collision Avoidance

Zhang,

Jiang

2023

Sustainability

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The probability of collisions at sea has increased in recent years. Furthermore, passive collision avoidance has some disadvantages, such as low economic efficiency, while active collision avoidance techniques have some limitations. As a result of the advancement of computer technology, active collision avoidance techniques have also been optimized by using artificial intelligence-based methods. The purpose of this paper is to further the development of the field. After reviewing some passive collision avoidance schemes, the paper discusses the potential of active obstacle avoidance techniques. A time-tracing approach is used to review the evolution of active obstacle avoidance techniques, followed by a review of the main traditional active obstacle avoidance techniques. In this paper, different artificial intelligence algorithms are reviewed and analyzed. As a result of the analysis and discussion in this paper, some limitations in this field are identified. In addition, there are some suggestions and outlooks for addressing those limitations. In a way, the paper can serve as a guide for the development of the field.

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“…However, some analytical research has also shown that the smooth dropwise surface will have better heat transfer characteristics than that of the Wenzel and Cassie–Baxter surfaces. 11,21…”

Section: Introductionmentioning

confidence: 99%

“…However, some analytical research has also shown that the smooth dropwise surface will have better heat transfer characteristics than that of the Wenzel and Cassie-Baxter surfaces. 11,21 Although DWC and hybrid hydrophobic-hydrophilic surfaces are major areas of interest in heat transfer, little research has been conducted on the impact of the Marangoni convection on dropwise heat transfer, exclusively when micro/nanostructures have been implemented on the dropwise region. Investigations were primarily experimental and were carried out to study and simulate an individual and single droplet, little research has been carried out to investigate the impact of Marangoni convection on hybrid hydrophobic-hydrophilic surfaces.…”

Section: Introductionmentioning

confidence: 99%

Theoretical analysis on condensation heat transfer on the hydrophobic–hydrophilic hybrid surfaces with the impact of the Marangoni convection

Vatanjoo

Aminian

Kamali

et al. 2022

Proceedings of the Institution of Mechanical Engineers, Part E:

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Condensation occurs in the forms of filmwise condensation and dropwise condensation. Over the past decade, hybrid hydrophobic–hydrophilic surfaces have received significant attention due to their potential to enhance the heat transfer rate compared to complete dropwise condensation. The maximum condensed droplet radius in the hydrophobic region has a considerable impact on the heat transfer characteristics. This paper discusses the effect of the maximum droplet radius on hybrid surface heat transfer characteristics. On top of that, Marangoni convection effects originated due to the temperature gradient as a heat transfer resistance on the heat transfer rate is considered, modelled and investigated. Three models were investigated in this paper. The results indicate that there is an optimum maximum droplet radius for each model that can improve the heat transfer rate. When the filmwise region width increases from 0.5 mm to 1.0 mm, the optimum maximum droplet radius increases from 0.25 mm to 0.3 mm. For a fixated droplet contact angle and filmwise and dropwise region widths, the hybrid heat flux of the smooth dropwise model can be up to 1.55 times higher than that of the Cassie–Baxter model, and the hybrid heat flux of the smooth dropwise model can be up to 1.38 time higher than that of the Wenzel state. Finally, considering Marangoni convection showed up to a 30% increase in the heat transfer coefficient in some cases.

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Theoretical analysis on condensation heat transfer on microstructured hybrid hydrophobic-hydrophilic tube

Cited by 9 publications

References 33 publications

A numerical study on effect of intra and inter spaced winding configuration on performance of oil forced transformer cooling system

A numerical study on effect of intra and inter spaced winding configuration on performance of oil forced transformer cooling system

A Review of Artificial Intelligence-Based Optimization Applications in Traditional Active Maritime Collision Avoidance

Theoretical analysis on condensation heat transfer on the hydrophobic–hydrophilic hybrid surfaces with the impact of the Marangoni convection

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