Статті в журналах: "Enhancement of thermo-hydraulic performance"

1

Alam, Mir Waqas, and Basma Souayeh. "Parametric CFD Thermal Performance Analysis of Full, Medium, Half and Short Length Dimple Solar Air Tube." Sustainability 13, no. 11 (June 7, 2021): 6462. http://dx.doi.org/10.3390/su13116462.

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In the present decade, research regarding solar thermal air heaters (SAHs) has noticed a continuous progression in thermo-hydraulic performance augmentation approaches. There now exists a wide variety of thermo-hydraulic performance augmentation approaches and researchers have designated various structures. Nevertheless, there seems to be no generalization to any of the approaches employed. The present numerical investigation reports on the thermo-hydraulic characteristics and thermal performance for flow through a varied length (full, medium, half, and short length) dimple solar air heater (SAH) tube. The study highlights recent developments on enhanced tubes to augment heat transfer in SAH. The influence of different length ratio, dimple height ratio (H), and pitch ratio (s) on thermo-hydraulic characteristics have been investigated in the Reynolds number (Re) range from 5000 to 25,000. Air is used as the working fluid. The commercial software ANSYS Fluent is used for simulation. The shear stress transport (SST) model is used as the turbulence model. Thermal energy transport coefficient is increased in the full-length dimple tube (FLDT), compared to the medium-length dimple tube (MLDT), half-length dimple tube (HLDT) and short-length dimple tube (SLDT). Similarly, the pitch ratio (s) has more influence on Nusselt number (Nu) compared to the dimple height ratio (H). The friction factor decreases with an increase in pitch ratio. Nu increases and f decreases with increasing Re for all combinations of H and s. Low s and higher H yields high enhancement of HT and PD. Integration of artificial roughness on the tube increases the values of Nu and f by 5.12 times and 77.23 times for H = 0.07, s = 1.0 at Re value of 5000 and 25,000, respectively, in regard to the plain tube. For all the tested cases, the thermo-hydraulic performances (η) are greater than unity.

2

Kumar, Thakur Sanjay, N. S. Thakur, Anoop Kumar, and Vijay Mittal. "Use of artificial roughness to enhance heat transfer in solar air heaters – a review." Journal of Energy in Southern Africa 21, no. 1 (February 1, 2010): 35–51. http://dx.doi.org/10.17159/2413-3051/2010/v21i1a3248.

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Improvement in the thermo hydraulic performance of a solar air heater can be done by enhancing the heat transfer. In general, heat transfer enhancement techniques are divided into two groups: active and passive techniques. Providing an artificial roughness on a heat transferring surface is an effective passive heat transfer technique to enhance the rate of heat transfer to fluid flow. In this paper, reviews of various artificial roughness elements used as passive heat transfer techniques, in order to improve thermo hydraulic performance of a solar air heater, is done. The objective of this paper is to review various studies, in which different artificial roughness elements are used to enhance the heat transfer rate with little penalty of friction. Correlations developed by various researchers with the help of experimental results for heat transfer and friction factor for solar air heater ducts by taking different roughened surfaces geometries are given in tabular form. These correlations are used to predict the thermo hydraulic performance of solar air heaters having roughened ducts. The objective is to provide a detailed review on heat transfer enhancement by using an artificial roughness technique. This paper will be very helpful for the researchers who are researching new artificial roughness for solar air heater ducts to enhance the heat transfer rate and comparing with artificial roughness already studied by various researchers.

3

Saghir, Mohamad Ziad. "Thermo-Hydraulic Performance of Multiple Channels and Pin Fins Forming Convergent/Divergent Shape." Energies 15, no. 21 (October 27, 2022): 7993. http://dx.doi.org/10.3390/en15217993.

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Heat enhancement has been addressed by studying flow in channels with different shapes. The present paper investigates a particular channel shape with divergent and convergent forms. Two configurations are addressed: wall channels and pin-fin walls forming divergent/convergent shapes. The flow is assumed to be in a laminar and steady-state condition. The numerical model investigated the heat enhancement for different flow rates represented by Reynolds numbers. The average Nusselt number and the performance evaluation criterion revealed that wall channels outperformed the pin-fin shape. The performance evaluation criterion is higher than 1 for the wall channels. The main reason for this is that the flow passes through and above the wall creating mixing. This flow configuration happened since the wall height is shorter than the test cavity height. It is important to emphasize that pin-fins forming convergent channels did not improve heat enhancement when compared to convergent channels. No significant variation in the pressure drop was detected.

4

Singh, Ajeet Pratap, and O. P. Singh. "Thermo-hydraulic performance enhancement of convex-concave natural convection solar air heaters." Solar Energy 183 (May 2019): 146–61. http://dx.doi.org/10.1016/j.solener.2019.03.006.

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Dilip, D., S. Vijay Kumar, M. S. Bobji, and Raghuraman N. Govardhan. "Sustained drag reduction and thermo-hydraulic performance enhancement in textured hydrophobic microchannels." International Journal of Heat and Mass Transfer 119 (April 2018): 551–63. http://dx.doi.org/10.1016/j.ijheatmasstransfer.2017.11.093.

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Raj, Vijilius Helena, S. Vinod Kumar, Mohammed Hussein, Rahul Kadam, Dinesh Kumar Yadav, and Shekhar Sharma. "Enhancement of Thermo-Hydraulic Performance using Water-Based Alumina Nanofluids: A Numerical Investigation." E3S Web of Conferences 507 (2024): 01074. http://dx.doi.org/10.1051/e3sconf/202450701074.

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This study investigates the heat transfer and fluid flow characteristics of pure water passing through a double tube heat exchanger (DTHX). Computational fluid dynamics (CFD) simulations were conducted using ANSYS-FLUENT 22 R1 software. Mathematical models and thermophysical properties of nanofluids and water from existing literature were employed. The comparison focused on pure water and 1% Al2O3/H2O nanofluids. Various operating variables such as Reynolds number and temperature were considered across the inner and outer tubes. The Reynolds number ranged from 2500 to 5500 at 80°C for the inner tube and 2500 at 15°C for the outer tube. Key findings include a 7.69% increase in friction factor for 1% Al2O3/H2O compared to pure water and a 16% increase compared to the Gnielinski correlation at a Reynolds number of 2500. The Nusselt number (Nu) exhibited a 98.42% increase compared to the Gnielinski correlation at a Reynolds number of 5500 and a 39% increase compared to pure water at the same Reynolds number. Heat transfer coefficients (hi) were found to increase by 9.52% compared to pure water and 12% compared to the correlation in existing literature.

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Hasan, Ibtisam, Wafa Maki, and Yaser Enaya. "Thermo-hydraulic performance evaluation of heat exchanger tube with vortex generator inserts." Thermal Science 26, no. 2 Part B (2022): 1545–55. http://dx.doi.org/10.2298/tsci210528289h.

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This work is undertaken as a scientific experiment to test a new design of a turbulent generator. The current research experiments the influence of novel vortex generator inserts on heat transfers within a tube under a uniform heat flux. A Cu tube with a 45 mm inner diameter and 1350 mm length is used along with a solid disc injector (swirl generator) that comprises ten crescent holes with equal circumferential distribution angles around the disk canter. Subsequently, a swirl flow is generated by deviating the stream flow 45? causing it to spin in the direction of the axial flow. Flow directors are on 45? angles toward the axial direction for each of the crescent holes. This study is an example of flow degradation. Reynolds numbers range from 6000 to 13500. Therefore, fluid-flow is treated as a turbulent system. All experiments done with air are regarded as a power fluid and Prandtl number is fixed at about 0.71. Thermo-hydraulic performance of heat exchanger is analyzed. The average heat transfer Nusselt number is calculated and discussed. The experiment found out that Nusselt number increases with an increase in Reynolds number as well as the number of swirl generators. At four vortex generators, the maximum augmentation in heat transfer is around 4.3 times greater than the plain tube and friction factor is about 1.28 with 5 vortex generators insets. The results indicate a promising heat exchanger enhancement in the local petroleum industries.

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Lotfi, Babak, and Bengt Sundén. "Thermo-Hydraulic Performance Enhancement of Finned Elliptical Tube Heat Exchangers by Utilizing Innovative Dimple Turbulators." Heat Transfer Engineering 41, no. 13 (June 27, 2019): 1117–42. http://dx.doi.org/10.1080/01457632.2019.1611132.

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Nguyen Minh and Pham Ba Thao. "Thermohydraulic Performance of a Fin and Inclined Flat Tube Heat Exchanger: A Numerical Analysis." CFD Letters 13, no. 7 (July 25, 2021): 1–12. http://dx.doi.org/10.37934/cfdl.13.7.112.

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Proper determination of inclination angle of a flat tube may increase the overall heat transfer performance without extending heat transfer surface. In this paper, the inclined flat tube heat exchanger with plain fins is numerically investigated. The influence of flat tube inclination angle and Reynolds number on the thermo-hydraulic performance index was evaluated. Tube pitch, fin spacing and flat tube size are fixed. Solving 3D computational domain with the symmetric boundary condition is used to reduce computation time. The results show that when increasing the inclination angle of the flat tube from 0 to 45°, both heat transfer and pressure loss increase because the free area of air flow decreases leading to an increase in air velocity and impingement heat transfer. The variation of inclination angle from 0 to 15°, the increase in heat transfer is stronger than the increase in the pressure loss penalty, so the performance index reaches a maximum of 0.405 at the angle of 15°. Contours of temperature, pressure and velocity at different inclination angles are presented to clarify the thermo-hydraulic characteristics of finned-tube heat exchangers using inclined flat tubes. The current work yields heat transfer enhancement ability by adjusting inclination angle of a heat transfer flat tube.

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Parsazadeh, Mohammad, Farshid Fathinia, Amirhossein Heshmati, Mazlan Abdul Wahid, and Mohsin Mohd Sies. "Numerical Study on Heat Transfer of Turbulent Flow in a Channel with Composite Arrangement Obstacles." Applied Mechanics and Materials 388 (August 2013): 161–68. http://dx.doi.org/10.4028/www.scientific.net/amm.388.161.

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Forced convective heat transfer of turbulent flow in a two-dimensional channel mounted triangular and trapezoidal obstacles in upper wall and bottom wall arranged with periodic grooves is numerically studied. Continuity, momentum and energy equations are discretized with second order upwind method is applied to solve the equations. (RNG) k-ε model is implemented to predict the thermo-hydraulic performance of the flow. A thick of 3mm made up by aluminum is implemented for channel walls that the bottom and upper walls are heated with a uniform heat flux. The thermo-hydraulic effects of shapes and positions of obstacles mounted on upper wall referred to the bottom ribbed and grooved wall of the channel as well as its thermal enhancement factorare tested in a Reynolds number range of 3000 to 5000 with engine oil as working fluid. The numerical results demonstrate that combination of trapezoidal obstacles arrays of the upper wall placed against of ribs array of the bottom wall reveals highest thermal enhancement factor due to trapezoidal obstacles with increasing height in flow direction not only lead the flow to the bottom grooved wall but also the flow osculate surface of the obstacle and restart the thermal boundary layer with lowest friction factor compared to other cases.

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Vatsa, Aditya, Tabish Alam, Md Irfanul Haque Siddiqui, Masood Ashraf Ali, and Dan Dobrotă. "Performance of Microchannel Heat Sink Made of Silicon Material with the Two-Sided Wedge." Materials 15, no. 14 (July 6, 2022): 4740. http://dx.doi.org/10.3390/ma15144740.

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New designs of the microchannel with a two-sided wedge shape at the base were studied numerically. Five different wedge angles ranging from 3° to 15° were incorporated into the microchannel design. Simulation of this novel microchannel was carried out using Computational Fluid Dynamics (CFD). Three-dimensional models of the microchannel heat sink were created, discretized, and based on Navier–Stokes and energy equations; laminar numerical solutions were obtained for heat transfer and pressure drop. Flow characteristics of water as coolant in a microchannel were studied. It was observed that numerical results are in good agreement with experimental results. It was found that the Nusselt number and friction factor are significantly varied with the increase in Reynolds number. The Nusselt number varies in the following ranges of 5.963–8.521, 5.986–8.550, 6.009–8.568, 6.040–8.609, and 6.078–8.644 at 3°, 6°, 9°, 12°, and 15°, respectively. The microchannel with a wedge angle of 15° was found to be better in terms of Nusselt number and thermo-hydraulic performance. The enhancement in the Nusselt number is found as 1.017–1.036 for a wedge angle of 15°; however, friction factors do not show the perceptible values at distinct values of wedge angle. Moreover, the thermo-hydraulic performance parameters (THPP) were evaluated and found to be maximum in the range of 1.027–1.045 for a wedge angle of 15°. However, minimum THPP was found in the range of 1.005–1.0185 for a wedge angle of 3°.

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P, Jayesh, Mukkamala Y, and Bibin John. "Design and testing of energy-efficient heat exchangers for Newtonian and non-Newtonian fluids – A review." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 236, no. 3 (October 4, 2021): 575–606. http://dx.doi.org/10.1177/09576509211047000.

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Heat transfer enhancement, pumping power and weight minimization in enhanced heat exchangers has long been achieved by deploying tubes with internal surface modifications like microgrooves, ribs, fins, knurls, and dimples with and without tube inserts. This article presents a very extensive review of experimental and computational studies on heat transfer enhancement, which covers convectional and unconventional working fluids under different fluid flow conditions. Compound augmentation with tube surface modifications and inserts has yielded enhancements in the overall heat transfer coefficient of over 116% in the fully developed turbulent flow regime. Exotic fluids like nano-coolants deployed in spiral grooved mircofin tubes yielded 196% enhancement in tube side heat transfer rate for concentrations as low as 0.5% by volume, while the thermal efficiency index measuring the overall enhancement in relation to the pumping power was 75%. However, reviews that address the combined effect of unconventional fluids, surface modifications and tube inserts on the overall thermo-hydraulic performance of annular heat exchangers seem to be limited. Further, nano-coolants aren’t frequently used in the process industry. The goal of this study is to document and evaluate the impact of cost-effective and energy-saving passive enhancement techniques such as tube surface modifications, tube inserts, and annular enhancement techniques on annular heat exchangers used in the process industries with Newtonian and non-Newtonian fluids. This review should be useful to engineers, academics and medical professionals working with non-Newtonian fluids and enhanced heat exchangers.

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P, Jayesh, Mukkamala Y, and Bibin John. "Design and testing of energy-efficient heat exchangers for Newtonian and non-Newtonian fluids – A review." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 236, no. 3 (October 4, 2021): 575–606. http://dx.doi.org/10.1177/09576509211047000.

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Heat transfer enhancement, pumping power and weight minimization in enhanced heat exchangers has long been achieved by deploying tubes with internal surface modifications like microgrooves, ribs, fins, knurls, and dimples with and without tube inserts. This article presents a very extensive review of experimental and computational studies on heat transfer enhancement, which covers convectional and unconventional working fluids under different fluid flow conditions. Compound augmentation with tube surface modifications and inserts has yielded enhancements in the overall heat transfer coefficient of over 116% in the fully developed turbulent flow regime. Exotic fluids like nano-coolants deployed in spiral grooved mircofin tubes yielded 196% enhancement in tube side heat transfer rate for concentrations as low as 0.5% by volume, while the thermal efficiency index measuring the overall enhancement in relation to the pumping power was 75%. However, reviews that address the combined effect of unconventional fluids, surface modifications and tube inserts on the overall thermo-hydraulic performance of annular heat exchangers seem to be limited. Further, nano-coolants aren’t frequently used in the process industry. The goal of this study is to document and evaluate the impact of cost-effective and energy-saving passive enhancement techniques such as tube surface modifications, tube inserts, and annular enhancement techniques on annular heat exchangers used in the process industries with Newtonian and non-Newtonian fluids. This review should be useful to engineers, academics and medical professionals working with non-Newtonian fluids and enhanced heat exchangers.

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Tan, A. S. T., J. Janaun, H. J. Tham, N. J. Siambun, and A. Abdullah. "Performance enhancement of a baffle-type solar heat collector through CFD simulation study." IOP Conference Series: Materials Science and Engineering 1195, no. 1 (October 1, 2021): 012040. http://dx.doi.org/10.1088/1757-899x/1195/1/012040.

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Abstract The application of solar energy conversion has been extensively utilized as an alternative energy source to generate heat. This approach would be a step towards sustainable energy development particularly in the manufacturing industry with energy-intensive process. In this paper, thermal enhancement on the key component of a solar energy device – solar heat collector (SHC), has been evaluated by proposing a baffle-type SHC with various geometric configuration in the air passage namely longitudinal baffle and transversal baffle. The performance of SHC is evaluated in term of efficiency, temperature distribution, airflow pattern and pressure drop across the collector outlet through Computational Fluid Dynamic (CFD) investigation. It was observed that maximum collector efficiency was achieved in the Longitudinal-SHC (L-SHC), with a value of 46.2 % followed by Transversal-SHC (T-SHC) and without baffles. Maximum drying temperature at the collector outlet was 332.43 K for L-SHC, showing temperature rise of 0.35 % and 4.21 % from T-SHC and without baffles, respectively. The velocity vector indicated that turbulence flow was created in the T-SHC which consequently improved the heat transfer. Whereas in L-SHC, enhancement was achieved through the prolonged heating time in the passage. Considering the thermo-hydraulic performance factor evaluated, these enhancement features had diminished the effect of pressure drop.

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Gürsoy, Emrehan, Ezgi Çalar, Abdullah Dağdeviren, Hayati Kadir Pazarlıoğlu, Engin Gedik, and Kamil Arslan. "Thermo-hydraulic Performance Analysis of Al2O3/water Nanofluid Flow in a Tube Extended by Twisted Tape." INTERNATIONAL JOURNAL OF THERMAL-FLUID ENGINEERING AND MODERN ENERGETICS 1, no. 1 (July 2022): 34–47. http://dx.doi.org/10.51558/2831-0527.2022.1.1.34.

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In this numerical study, heat transfer characteristics and hydrodynamical analysis have been performed for a circular tube inserted with twisted tape, which has different twisted pitch ratios (TPR=0, 50, 100, and 200). As a working fluid Al2O3/water nanofluid is used which has different volumetric concentrations (0.0≤φ≤3.0 vol. %). The numerical analysis has been carried out under the constant wall heat flux (q′′) of 4357 W/m2 for laminar flow ranging the Reynolds (Re) number from 1000 to 2000. According to numerical results, the highest average Nusselt number (Nu) and average Darcy friction factor (ff) have realized in twisted pitch ratio (TPR) 50. The reason is that when the twisted pitch ratio gradually decreases, stronger secondary flows and a higher velocity can be obtained. When compared with water, the highest Nu for TPR=50 has been obtained at φ=3.0 vol. % concentration as 61.15%. Also, when compared with TPR=0, the highest thermal performance enhancement (TPE) was realized at φ=3.0 vol. % concentration and Re=2000 conditions as 61.15% for TPR=50. Keywords: CFD Convective heat transfer Laminar flow Al2O3/water Twisted tape

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Mogaji, Taye Stephen, Emmanuel Tolulope Idowu, and Tien-Chien Jen. "Numerical Simulation for Comparative Thermo-Hydraulic Performance of Turbulent Flow in Tubes with Twisted Tape Inserts." Journal of Engineering Science 16, no. 2 (December 10, 2020): 71–100. http://dx.doi.org/10.21315/jes2020.16.2.4.

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This article focused on investigating numerically the effects of key design parameters including tape thickness, tube wall to tape edge clearance and three different perforated shapes cut (circular, triangular and pentagon) on the heat transfer coefficient enhancement in tube with twisted tape inserts. Water was considered as the working fluid under the turbulent flow of Reynolds number (Re) between 12,000 and 22,000, with constant wall temperature of the tubes. It is found that due to the swirling flow and efficient mixing of the fluid, all the tape inserts considered in this study produced better thermalhydraulic performance than the plain tube without an insert. At the same time, tape inserts with small tube wall to tape edge clearance and considerable thickness value is beneficial to reduce the friction factor, consequently enhancing the heat transfer rate. Through the thermal performance factor (TPF) evaluation, the twisted tape with perforated triangular shape cut has an advantage over the pentagon and circular shapes cut with increasing Re. A maximum TPF as high as 1.68 can be obtained for the twisted tape with perforated triangular shape cut under low turbulent Re.

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UYANIK, Mahmut, Toygun DAĞDEVİR, and Veysel OZCEYHAN. "Thermo-hydraulic performance investigation of a heat exchanger tube inserted with twisted tapes modified with various twist ratio and alternate axis." European Mechanical Science 6, no. 3 (September 20, 2022): 189–95. http://dx.doi.org/10.26701/ems.1032081.

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This paper presents a numerical investigation on a heat transfer enhancement by using a computational fluid dynamics software. The heat transfer enhancement is implemented by inserting twisted tape into a heat exchanger tube. The twisted tapes with twist ratios of 4, 6 and 8 were modified with alternate axis. The pitch of the twisted tape having the rotation direction such as clockwise and counterclockwise are connected with 90º connection angle. Water is selected as working fluid and turbulent flow condition corresponding to Reynolds number ranging from 5000 to 29000 are considered in the study. The heat exchanger tube is under constant heat flux of 50 kW/m2. Numerical analysis results prove that the use of twisted tape improves thermal performance compared to smooth tube. As the twist ratio increased, the heat transfer performance and the friction loss penalty decreased. Overall results are determined with thermohydraulic performance criteria (THP). The highest THP value is obtained as 1.21 for the tube inserted with the twisted tape which has the twist ratio of 4 and alternate axis between the twist pitches at Reynolds number of 5913

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Birlie Fekadu, Harish H.V, and Manjunath. K. "Numerical Studies on Thermo-Hydraulic Characteristics of Turbulent Flow in a Tube with a Regularly Spaced Dimple on Twisted Tape." CFD Letters 13, no. 8 (August 10, 2021): 20–31. http://dx.doi.org/10.37934/cfdl.13.8.2031.

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Heat transfer augmentation is an important concern due to the increase in heat management problems in thermal systems. There are many techniques for enhancement of heat transfer, by active and passive techniques. A commonly used passive technique to enhance heat transfer is by inserting twisted tapes in tubes. This work presents a numerical study on Nusselt number, friction factor, and thermal performance characteristics through a circular pipe built-in with/without dimples on twisted tape. The analysis results for a turbulent flow range of 4500≤Re≤20000 are obtained with a twist ratio of the strip is 3.0. The analysis is carried for full-length tape with constant heat flux. The governing equations are numerically solved by a ﬁnite volume method using the RNG κ–ε model. The simulation results of Nusselt number versus Reynolds number of the plain, plain twisted tape and dimple twisted tape tube with the experimental data give a variation of 4.15%, 3.89%, and 7.65%. The friction factor of the dimple twisted tape tube is 60 to 70% higher than that of the plain twisted tube at different Reynolds numbers. The thermal performance factor of the dimple twisted tape and plain twisted tape tube is 30 to 35% respectively higher than that of the plain tube. Due to thermal performance factor is above unity yields a promising heat transfer enhancement. By the present study, an optimum geometrical parameter can be selected for use in heat exchangers.

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Ebrahimi, Amin, and Ehsan Roohi. "Numerical study of flow patterns and heat transfer in mini twisted oval tubes." International Journal of Modern Physics C 26, no. 12 (September 2015): 1550140. http://dx.doi.org/10.1142/s0129183115501405.

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Flow patterns and heat transfer inside mini twisted oval tubes (TOTs) heated by constant-temperature walls are numerically investigated. Different configurations of tubes are simulated using water as the working fluid with temperature-dependent thermo-physical properties at Reynolds numbers ranging between 500 and 1100. After validating the numerical method with the published correlations and available experimental results, the performance of TOTs is compared to a smooth circular tube. The overall performance of TOTs is evaluated by investigating the thermal-hydraulic performance and the results are analyzed in terms of the field synergy principle and entropy generation. Enhanced heat transfer performance for TOTs is observed at the expense of a higher pressure drop. Additionally, the secondary flow generated by the tube-wall twist is concluded to play a critical role in the augmentation of convective heat transfer, and consequently, better heat transfer performance. It is also observed that the improvement of synergy between velocity and temperature gradient and lower irreversibility cause heat transfer enhancement for TOTs.

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Ghalambaz, Mehdi, Ramin Mashayekhi, Hossein Arasteh, Hafiz Muhammad Ali, Pouyan Talebizadehsardari, and Wahiba Yaïci. "Thermo-Hydraulic Performance Analysis on the Effects of Truncated Twisted Tape Inserts in a Tube Heat Exchanger." Symmetry 12, no. 10 (October 9, 2020): 1652. http://dx.doi.org/10.3390/sym12101652.

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This paper investigates the convective heat transfer in a heat exchanger equipped with twisted tape elements to examine effects of the twisted tape truncation percentage, pitch value, position and Reynolds number using 3D numerical simulation. A symmetric heat flux is applied around the tube as the studied heat exchanger. Based on the influences in both heat transfer enhancement and pressure drop, the performance evaluation criterion (PEC) is utilized. Inserting twisted tape elements and reducing the pitch value significantly augment the Nusselt number, friction coefficient and PEC number compared to the plain tube. For the best case with a Reynolds number of 1000, the average Nusselt number increases by almost 151%, which is the case of fully fitted twisted tape at a pitch value of L/4. Moreover, increasing the twisted tape truncation percentage reduces both heat transfer and pressure drop. Furthermore, the highest heat transfer rate is achieved when the truncated twisted tape is located at the entrance of the tube. Finally, it is concluded that for P = L, L/2, L/3 and L/4, the optimum cases from the viewpoint of energy conservation are twisted tapes with truncation percentages of 75, 50, 50 and 0%, in which the related PEC numbers at a Reynolds number of 1000 are almost equal to 1.08, 1.24, 1.4 and 1.76, respectively.

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Mishra, Arin, Aman Mehrotra, and S. Senthur Prabu. "Study on Performance Analysis of a Solar Air Heater with Aerofoil Shaped Rib Roughness Using CFD." ECS Transactions 107, no. 1 (April 24, 2022): 16065–79. http://dx.doi.org/10.1149/10701.16065ecst.

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Present study investigates the heat transfer, friction factor and fluid flow characteristics of fully developed turbulent flow in a rectangular duct of solar air heater having aerofoil shaped rib-roughness on underside of absorber plate. ANSYS 14.5 has been used to simulate air flow through roughened air heater duct. Effect of relative roughness height and roughness pitch on Nusselt number and friction factor of roughened duct have been investigated and compared with that of smooth duct. It is found that the Nusselt number improves by attaching the roughness. Maximum enhancement in Nusselt number has been found to be 3.15 times over the smooth duct for rib roughness pitch P=15 mm, rib height e=7 mm, relative roughness height e/Dh=0.128, and aspect ratio of duct W/H=10. It is observed that the thermo-hydraulic performance parameter for roughened duct is greater than that obtained for smooth duct.

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Choi, Hwi-Ung, Kwang-Am Moon, Seong-Bhin Kim, and Kwang-Hwan Choi. "CFD Analysis of the Heat Transfer and Fluid Flow Characteristics Using the Rectangular Rib Attached to the Fin Surface in a Solar Air Heater." Sustainability 15, no. 6 (March 17, 2023): 5382. http://dx.doi.org/10.3390/su15065382.

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This study discussed the effect of ribbed fin, which was suggested by the authors, on the enhancement of heat transfer and flow characteristics of fluid in a solar air heater. The ribbed fin has a rectangular rib at the base and side surfaces of the fin. Thus, it can increase the heat transfer coefficient in the fluid field of a solar air heater as well as extend the heat transfer area. The simulation was performed with various Reynolds numbers, relative heights, and pitches of the rib. The presence of the rib enhances the heat transfer performance by 3.497 times over a smooth fin. However, the addition of the rib also increases pressure drop. Thus, the thermo-hydraulic performance, which considers both heat transfer enhancement and pressure drop increase, was also discussed. Furthermore, this study developed correlations for the Nusselt number and friction factor as a function of geometric condition of the rib and Reynolds number. The correlations accurately predicted the Nusselt number for the base and side surfaces of the fin and friction factor with mean absolute percent errors of 4.24%, 4.53%, and 7.33%, respectively.

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Ali, Sadiq, Faraz Ahmad, Kareem Akhtar, Numan Habib, Muhammad Aamir, Khaled Giasin, Ana Vafadar, and Danil Yurievich Pimenov. "Numerical Investigation of Microchannel Heat Sink with Trefoil Shape Ribs." Energies 14, no. 20 (October 17, 2021): 6764. http://dx.doi.org/10.3390/en14206764.

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The present study investigates the thermo-hydraulic characteristics of a microchannel sink with novel trefoil Shaped ribs. The motivation for this form of rib shape is taken from the design of lung alveoli that exchange oxygen and carbon dioxide. This study has been conducted numerically by using a code from the commercially available Fluent software. The trefoil shaped ribs were mounted on the centerline of different walls of the microchannel in three different configurations. These consisted of base wall trefoil ribs (MC-BWTR), sidewall trefoil ribs (MC-SWTR), all wall trefoil ribs (MC-AWTR) and smooth channel (MC-SC) having no ribs on its wall. The streamline distance between the ribs was kept constant at 0.4 mm, and the results were compared by using pressure drop (∆p), Nusselt number (Nu), thermal resistance (Rth) and thermal enhancement factor (η). The results indicated that the addition of trefoil ribs to any wall improved heat transfer characteristics at the expense of an increase in the friction factor. The trends of the pressure drop and heat transfer coefficient were the same, which indicated higher values for MC-AWTR followed by MC-SWTR and a lower value for MC-BWTR. In order to compare the thermal and hydraulic performance of all the configurations simultaneously, the overall performance was quantified in terms of the thermal enhancement factor, which was higher than one in each case, except for MC-AWTR, in 100 < Re < 200 regimes. The thermal enhancement factor in the ribbed channel was the highest for MC-SWTR followed by MC-BWTR, and it was the lowest for MC-AWTR. Moreover, the thermal enhancement factor increases with the Reynolds number (Re) for each case. This confirms that the increment in the Nusselt number with velocity is more significant than the pressure drop. The highest thermal enhancement factor of 1.6 was attained for MC-SWTR at Re = 1000, and the lowest value of 0.87 was achieved for MC-AWTR at Re = 100.

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Pandey, Navneet Kumar, and V. K. Bajpai. "Thermo-hydraulic performance enhancement of solar air heater (SAH) having multiple arcs with gap shaped roughness element on absorber plate." International Journal of Engineering, Science and Technology 8, no. 1 (November 4, 2016): 34. http://dx.doi.org/10.4314/ijest.v8i1.3.

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25

Boonloi, Amnart, and Withada Jedsadaratanachai. "Variations of heat transfer mechanism and flow structure in a heat exchanger tube fitted with 30° inclined ring." Advances in Mechanical Engineering 12, no. 3 (March 2020): 168781402091148. http://dx.doi.org/10.1177/1687814020911480.

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Flow prediction, heat transfer pattern, and thermo-hydraulic efficiency in a heat exchanger tube fitted with vortex generator are chosen for the present research. The 30° inclined ring is opted to develop the performance of the heat exchanger tube. The effects of inclined ring configuration and placement in the heat exchanger tube on the patterns of flow and heat transfer are investigated. The Reynolds number (at the entry zone of the periodic model) in the range of around 100–2000 (laminar flow region) is discussed. The heat transfer ability, pressure loss, and efficiency of the heat exchanger tube fitted with 30° inclined ring are analyzed with the numerical method (finite volume method). The SIMPLE algorithm of the commercial code is picked for the present study. The simulated results in the heat exchanger tube fitted with 30° inclined ring are offered in patterns of streamlines, temperature contour, and Nusselt number contour. From the preliminary result, it is found that the creation model of the heat exchanger tube fitted with 30° inclined ring has sufficient reliance to measure flow and heat transfer profiles. The installment of the 30° inclined ring in the heat exchanger tube leads to greater heat transfer ability and thermo-hydraulic performance because of the creation of the vortex flow and thermal boundary layer disturbance on the heat exchanger tube surface. The heat transfer ability in the heat exchanger tube fitted with 30° inclined ring is found to be around 1.00–10.56 times above the plain circular tube. In addition, the installation of the 30° inclined ring in the heat exchanger tube gives the maximum thermal enhancement factor around 3.18.

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Zhang, Ting, Chun J. Liu, Kai Guo, and Zhe Q. Huang. "Enhancement on Thermal-Hydraulic Performance of Serpentine Air Preheater." Journal of Chemical Engineering of Japan 49, no. 5 (2016): 435–44. http://dx.doi.org/10.1252/jcej.15we104.

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Huang, Chen, Yang, Du, and Yang. "Cooling Performance Enhancement of Air-Cooled Condensers by Guiding Air Flow." Energies 12, no. 18 (September 11, 2019): 3503. http://dx.doi.org/10.3390/en12183503.

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Adverse wind effects on the thermo-flow performances of air-cooled condensers (ACCs) can be effectively restrained by wind-proof devices, such as air deflectors. Based on a 2 × 300 MW coal-fired power generation unit, two types (plane and arc) of air deflectors were installed beneath the peripheral fans to improve the ACC’s cooling performance. With and without air deflectors, the air velocity, temperature, and pressure fields near the ACCs were simulated and analyzed in various windy conditions. The total air mass flow rate and unit back pressure were calculated and compared. The results show that, with the guidance of deflectors, reverse flows are obviously suppressed in the upwind condenser cells under windy conditions, which is conducive to an increased mass flow rate and heat dissipation and, subsequently, introduces a favorable thermo-flow performance of the cooling system. When the wind speed increases, the leading flow effect of the air deflectors improves, and improvements in the ACC’s performance in the wind directions of 45° and –45° are more satisfactory. However, hot plume recirculation may impede performance when the wind direction is 0°. For all cases, air deflectors in an arc shape are recommended to restrain the disadvantageous wind effects.

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Ranjan, Prabhat, Mohit Bhola, Gyan Wrat, Santosh Kr Mishra, and Jayanta Das. "Performance enhancement of hybrid hydraulic excavator using multiple hydro-pneumatic accumulators." Proceedings of the Institution of Mechanical Engineers, Part I: Journal of Systems and Control Engineering 234, no. 10 (March 10, 2020): 1133–49. http://dx.doi.org/10.1177/0959651820904274.

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In this article, the heavy earth moving machinery like hydraulic excavator used in the construction and mining industries has been taken into consideration. Most of the heavy earth moving machineries used in these industries are mobile with engine as the main source of power. The work deals with two different hydraulic circuits: first the proposed one and second the conventional one, and both are studied at laboratory scale, which resembles the circuit of the hydraulic excavator. In the hydraulic circuit, out of the three hydraulic linear actuators, two are connected with hydro-pneumatic accumulators and one hydro-motor is also taken into consideration, which resembles the boom, arm, bucket and swing motor, respectively. The idea behind the proposed circuit is to store substantial potential energy during downward movement of the two linear actuators in the accumulators, which resembles the boom and arm cylinder of the excavator. The stored energy is used for upward motion of the two actuators without utilizing any energy from the main pump. For the devised strategy, MATLAB/Simulink environment has been utilized for developing the simulation model and the same has been validated with the experimental data with reasonable accuracy. The effect of accumulator volume and pre-charge pressure has been studied for optimization of the accumulator size on the validated simulation model. This concept helps in saving 14.06% energy than its conventional counterpart which does not have the energy storage elements. The linear position control of the boom and the arm actuator in the proposed circuit have been accomplished using proportional–integral–derivative control and pressure-compensated proportional flow control valve and have been achieved with reasonably accuracy.

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Kumar, Kodi Rajesh, and Aabid Hussain Shaik. "Synthesis, thermophysical characterization and thermal performance analysis of novel Cu-MXene hybrid nanofluids for efficient coolant applications." RSC Advances 13, no. 42 (2023): 29536–60. http://dx.doi.org/10.1039/d3ra05429b.

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R., R., D. Jayasutha, Indu Nair V., R. Senthilraja, Subash Thanappan, and Ramya S. "Development Of Digital Twin Technology in Hydraulics Based on Simulating and Enhancing System Performance." Journal of Cybersecurity and Information Management 13, no. 2 (2024): 50–65. http://dx.doi.org/10.54216/jcim.130204.

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DT digital twin technology has become an essential tool in hydraulic systems. It not only offers a virtual representation of the actual plant, but also real-time monitoring and optimization of that same machinery. Digital Twin (DT) technology has become a cornerstone in the optimization of industrial processes, particularly in the domain of hydraulic systems. For example, this research aims to use digital twin technology to detect and fix leaks in hydraulic systems. By integrating advanced simulation algorithms for accurate leak detection and performance enhancement, this study presents a comprehensive framework. Combining techniques developed from both data-driven and state-of-the-art optimization methods our approach looks to change how leaks are detected in hydraulics. Our test introduces a comprehensive framework that not only accurately identifies leaks but also employs advanced simulation algorithms for subsequent performance enhancement. By bringing together data-driven insights and cutting-edge optimization methods, our work at the frontier of revolutionizing leak detection in hydraulic systems.

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Gong, Wenchi, Jun Shen, Wei Dai, Zeng Deng, and Maoqiong Gong. "Thermal-hydraulic performance enhancement analysis of microtube with superhydrophobic surfaces." International Journal of Heat and Mass Transfer 144 (December 2019): 118697. http://dx.doi.org/10.1016/j.ijheatmasstransfer.2019.118697.

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32

Hamadouche, Abdelmalek, Abdelwahid Azzi, Said Abboudi, and Rachid Nebbali. "Enhancement of heat exchanger thermal hydraulic performance using aluminum foam." Experimental Thermal and Fluid Science 92 (April 2018): 1–12. http://dx.doi.org/10.1016/j.expthermflusci.2017.10.035.

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33

Hassan, Jafar Mehdi, and Moayed Waleed Moayed. "The Effect of Hydraulic Accumulator on the Performance of Hydraulic System." Journal of Engineering 20, no. 07 (June 19, 2023): 174–90. http://dx.doi.org/10.31026/j.eng.2014.07.12.

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The purpose of this paper is to depict the effect of adding a hydraulic accumulator to a hydraulic system. The experimental work includes using measuring devices with interface to measure the pressure and the vibration of the system directly by computer so as to show the effect of accumulator graphically for real conditions, also the effects of hydraulic accumulator for different applicationshave been tested. A simulation analysis of the hydraulic control system using MATLAB.R2010b to study was made to study the stability of the system depending on the transfer function, to estimate the effect of adding the accumulator on stability of the system. A physical simulation test was made for the hydraulic system using MATLAB to show the effect of the accumulator when it's connected to the system for different parameters and compare it with a PID controller. The hydraulic system has been simulated and tested using Automation Studio (AS) to measure different data such as the linear speed of hydraulic cylinder and the effect of connecting the accumulator to the system. All the results showed that the hydraulic accumulator has a great benefits and a large enhancement to the hydraulic system.

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Vakiloroaya, Vahid, Bijan Samali, Stephen Cuthbert, Kambiz Pishghadam, and David Eager. "Thermo-economic optimization of condenser coil configuration for HVAC performance enhancement." Energy and Buildings 84 (December 2014): 1–12. http://dx.doi.org/10.1016/j.enbuild.2014.07.079.

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35

Aljelawy, Ali M., Amer M. Aldabbagh, and Falah F. Hatem. "Numerical Investigation of Thermal Hydraulic Performance of Printed Circuit Heat Exchanger of Periodic Diamond Channel Shape." IOP Conference Series: Earth and Environmental Science 961, no. 1 (January 1, 2022): 012010. http://dx.doi.org/10.1088/1755-1315/961/1/012010.

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Abstract One of the most recently important heat exchangers is the Printed circuit heat exchanger especially in the nuclear power plant and aerospace applications due to its very compact geometry and small print foot. This paper presents a 3D numerical investigation on the thermo-hydraulic performance of PCHE with new non-uniform channel design configuration. The new channel design is a rectangular cross section with repeated converging diverging sections or periodic diamond shape. The influence of three design parameters on the heat exchanger performance was studied and optimized, pitch length (p), length ratio (β) and the converging diverging angle (α). The computational models investigated in this study based on the operating conditions of the intermediate heat exchanger of very high temperature gas cooled reactor with helium as the working fluid under operating pressure of 3Mpa and inlet temperature of 800 K. The Reynolds number varied from 200 to 2000. Different Pitch lengths were used (1.59, 3.18, 6.36, and 12.73) mm, and different C-D angle (0, 4.5, 6, 7.5, 9, 10.5 and 12) and also different length ratios were used (0.2, 0.25 and 0.333). Three performance parameters were studied the Nusselt number, friction factor and the overall performance evaluation factor. Results show that the thermal performance enhanced with decreasing the pitch length and with increasing C-D angle and it was shown that this enhancement was found only at high Reynolds number above 1400. The best performance obtained at p=3.18, α=6 and β=0.25 based on the overall evaluation performance.

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Po-Ngaen, Watcharin, and J. Maka. "Enhancement the Maneuverability of Tele-Hydraulic System Using Fuzzy Friction Compensator." Applied Mechanics and Materials 752-753 (April 2015): 995–99. http://dx.doi.org/10.4028/www.scientific.net/amm.752-753.995.

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One degree of freedom (DOF) tele-hydraulic manipulation using force reflecting bilateral control will be investigated. The primary objective in the development of a simple one DOF experimental rig was to allow the investigation of different tele-control strategies prior to their implementation on the eight DOF tele-hydraulic excavator system. Because of the friction nonlinearity characteristic in hydraulic system, high steady state error and overshoot have occurred in the position response as a typical imperfect implementation of associated control dynamic. In this situation, there is a necessity to be able to effectively utilizing the intelligent friction compensated controller. This fuzzy compensator combined with fuzzy controller will be implemented to enhance the maneuverability performance. Experiments were carried out and the experimental results illustrated that the above compensated intelligent framework can improve the bilateral performance

37

Bose, A., S. Chakraborty, and S. S. Mukhopadhayay. "Thermo-Hydraulic Performance Enhancement of Liquid He Based Cryogenic Nanofluid Flow in Laminar Region Through Rectangular Plate Fin Heat Exchangers -A Numerical Study." IOP Conference Series: Materials Science and Engineering 998 (December 23, 2020): 012001. http://dx.doi.org/10.1088/1757-899x/998/1/012001.

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38

Mahmoudi, Ashkan, Mahyar Fazli, Mohammad Reza Morad, and Ehsan Gholamalizadeh. "Thermo-hydraulic performance enhancement of nanofluid-based linear solar receiver tubes with forward perforated ring steps and triangular cross section; a numerical investigation." Applied Thermal Engineering 169 (March 2020): 114909. http://dx.doi.org/10.1016/j.applthermaleng.2020.114909.

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39

Asrul, S. Y., M. S. Risby, A. R. Sarip, M. I. Saiddi, and W. A. W. Mat. "Conceptual design of hydraulic hybrid test rig for engine performance enhancement." Journal of Fundamental and Applied Sciences 9, no. 3S (January 16, 2018): 70. http://dx.doi.org/10.4314/jfas.v9i3s.6.

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40

Sudharani Panda and Rakesh Kumar. "A Review on Heat Transfer Enhancement of Solar Air Heater Using Various Artificial Roughed Geometries." Journal of Advanced Research in Fluid Mechanics and Thermal Sciences 89, no. 1 (December 5, 2021): 92–133. http://dx.doi.org/10.37934/arfmts.89.1.92133.

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Solar air heater acts as one of the important components in utilization of solar energy. The air heater absorbs the irradiance and converts it into heat energy at the absorbing surface. The thermal energy is further use in heating flowing air through the duct. Solar air heaters are cost effective as well as simple in design. Solar air heater can be used in space heating, timber seasoning and agricultural drying. In spite of all these advantages the solar air heater has certain challenges such as the air has low heat transfer coefficient. The heat transfer rate from the heated absorber surface to the air is low. Hence in order to enhance the heat transfer coefficient the surface area either increases or the flow made to be turbulent. In order to do so the artificial roughened element must be incorporated on the heated surface. The use of artificial roughness is considered as an effective technique to enhance the heat transfer rate of fluid flowing through the duct of solar air heater. The heat transfer and friction characteristics of number of roughness geometries incorporated solar air heater have been investigated. In this paper an attempt has been made to review on element geometries used as artificial roughness in solar air heater in order to improve thermal and thermo hydraulic performance of solar air heater ducts.

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Akhtari, Hosein, and Ardalan Shafiei Ghazani. "Enhancement in thermo-hydraulic performance of ceramic-based disk heat sink with fractal micro-channels via double layering, hybrid nanofluids, and cross-sectional convergence." International Journal of Heat and Fluid Flow 107 (July 2024): 109418. http://dx.doi.org/10.1016/j.ijheatfluidflow.2024.109418.

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42

Geng, Dazhou, Qijuan Chen, Yang Zheng, Xuhui Yue, and Donglin Yan. "Enhancement of dynamic performance of wave energy converter by introducing a flow control." Transactions of the Institute of Measurement and Control 44, no. 10 (January 12, 2022): 1922–38. http://dx.doi.org/10.1177/01423312211069978.

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The stabilization of power take-off (PTO) is imperative especially under circumstances of fluctuating input wave energy. In this paper, a flow control valve is introduced to optimize the transient process of the hydraulic PTO, which can contribute to a quicker adjustment and a stronger stability. Under variations of input power and load torque in transient process, an open-loop control method and a closed-loop control method are proposed as the opening law of the above valve, and the hydraulic motor speed, the pressure at the accumulator inlet and the generated power are chosen as indicators to examine the regulation performance. Then, the synergic effect of the flow control valve and the accumulator in the transient process is discussed. The effectiveness of the two presented control methods on the fluctuation suppression is respectively tested and compared in both regular wave and irregular wave situations via simulation. To validate the practical effectiveness of the proposed methods, field experiments are conducted. The results demonstrate that the open-loop control can only improve the damping ability of the hydraulic PTO in the speed raising stage, while the closed-loop control can improve the stability both in the speed raising stage and in the load increasing stage.

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Li, Jianying, Lingbing Kong, Heng Liang, Weidong Li, and Saad Aldosary. "Enhancing Electro-Hydraulic Load Simulator Performance Through Variable Arm Length and Particle Swarm-Optimized Controllers." Journal of Nanoelectronics and Optoelectronics 18, no. 9 (September 1, 2023): 1085–99. http://dx.doi.org/10.1166/jno.2023.3490.

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This study presents a novel approach to improve the loading characteristics of an electro-hydraulic load simulator by introducing a variable arm length mechanism and employing advanced control strategies rooted in Particle Swarm Optimization (PSO). The design enhancements focus on optimizing the physical connection between the steering gear system and the load system, resulting in an electro-hydraulic load simulator equipped with adjustable arm length. Through a meticulous analysis of the ideal pivot position for the rocker lever, a fuzzy Proportional-Integral-Derivative (PID) controller based on PSO has been developed for the steering gear system. In recognition of the PSO algorithm’s susceptibility to local optima convergence, a fuzzy PID controller employing Single-Particle Random Search (SSPSO) has also been devised for the load system. To assess the effectiveness of this innovative hardware configuration and controller implementation in mitigating over-suppression, comprehensive joint simulation experiments were conducted. The results unequivocally indicate that the incorporation of the variable arm length structure, along with the PSO-based fuzzy PID controller optimized using binding factors, substantially enhances the dynamic loading performance of the electro-hydraulic load simulator. This enhancement translates into superior loading accuracy and overall performance metrics, establishing this research as a valuable reference for future investigations in this field.

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Wu, Ge Ping, and Ping Lu. "Numerical Study of Heat Transfer Enhancement in Microchannels of the MTPV Systems." Applied Mechanics and Materials 316-317 (April 2013): 119–23. http://dx.doi.org/10.4028/www.scientific.net/amm.316-317.119.

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Heat transfer and fluid flow in the microchannel cooling passages with three different types of the MTPV systems are numerically investigated. The heat transfer characteristics and thermal performance of the microchannels are analyzed using different Reynolds numbers and hydraulic diameters. Local heat transfer coefficient, total pumping power, heat transferred are obtained from the simulations and the performance is discussed in terms of heat transfer coefficient and thermal efficiency. Results indicated enhanced performance with the smaller hydraulic diameters, and slighter penalty in pumping power. The increase in Reynolds number cause an increase in the heat transfer coefficient at the expense of decreased thermal efficiency. It is also found that the highest heat transfer coefficient is expected in rod bundles microchannels. However, round microchannels have a better thermal efficiency than others.

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Saha, Surojit, Tabish Alam, Md Irfanul Haque Siddiqui, Mukesh Kumar, Masood Ashraf Ali, Naveen Kumar Gupta, and Dan Dobrotă. "Analysis of Microchannel Heat Sink of Silicon Material with Right Triangular Groove on Sidewall of Passage." Materials 15, no. 19 (October 10, 2022): 7020. http://dx.doi.org/10.3390/ma15197020.

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Microchannel heat sink (MCHS) is a promising solution for removing the excess heat from an electronic component such as a microprocessor, electronic chip, etc. In order to increase the heat removal rate, the design of MCHS plays a vital role, and can avoid damaging heat-sensitive components. Therefore, the passage of the MCHS has been designed with a periodic right triangular groove in the flow passage. The motivation for this form of groove shape is taken from heat transfer enhancement techniques used in solar air heaters. In this paper, a numerical study of this new design of microchannel passage is presented. The microchannel design has five variable groove angles, ranging from 15° to 75°. Computational fluid dynamics (CFD) is used to simulate this unique microchannel. Based on the Navier–Stokes and energy equations, a 3D model of the microchannel heat sink was built, discretized, and laminar numerical solutions for heat transfer, pressure drop, and thermohydraulic performance were derived. It was found that Nusselt number and thermo-hydraulic performance are superior in the microchannel with a 15° groove angle. In addition, thermohydraulic performance parameters (THPP) were evaluated and discussed. THPP values were found to be more than unity for a designed microchannel that had all angles except 75°, which confirm that the proposed design of the microchannel is a viable solution for thermal management.

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Pereira, Sergio Luiz, Guilherme F. Fa Sortino, Eduardo Mário Dias, and Maria Lídia Rebello Pinho Dias. "Methodology for Enhancement of Energy Efficiency in Hydraulic Equipment." MATEC Web of Conferences 214 (2018): 04002. http://dx.doi.org/10.1051/matecconf/201821404002.

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The cost of energy has increased greatly in the last decades, even with technological impact attenuators, which brings a concern with the increase of production effectiveness and better use of energy by machines and advanced equipment in industrial plants. This article proposes a methodology that allows a more rational use of energy in the production environment, applying Automation Technology, which represents a more affordable approach in relation to the high capital demanding complete machine replacement by the latest highest efficiency version available. The methodology thus contribute to reducing capital consumption, reducing costs, impacting both in the productive and financial performance of the organizations, with the overall result meaning less damage to the environment, providing sustainable gains.

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Promvonge, Pongjet, and Sompol Skullong. "Thermal-hydraulic performance enhancement of solar receiver channel by flapped V-baffles." Chemical Engineering Research and Design 182 (June 2022): 87–97. http://dx.doi.org/10.1016/j.cherd.2022.03.051.

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Ghahremannezhad, Ali, and Kambiz Vafai. "Thermal and hydraulic performance enhancement of microchannel heat sinks utilizing porous substrates." International Journal of Heat and Mass Transfer 122 (July 2018): 1313–26. http://dx.doi.org/10.1016/j.ijheatmasstransfer.2018.02.024.

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Sung, Jong Hun, Taewan Kim, Soljin Kim, Fuead Hasan, Sangram Keshari Mohanty, Madhusudana Koratikere Srinivasa, Sri Charan Reddy, and Hyun Deog Yoo. "Li3PO4-Coated Graphite Anode for Thermo-Electrochemically Stable Lithium-Ion Batteries." Energies 16, no. 17 (August 23, 2023): 6141. http://dx.doi.org/10.3390/en16176141.

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Extensive research on electrode materials has been sparked by the rising demand for high-energy-density rechargeable lithium-ion batteries (LIBs). Graphite is a crucial component of LIB anodes, as more than 90% of the commercialized cathodes are coupled with the graphite anode. For the advanced graphite anode, the fast charge–discharge electrochemical performance and the thermal stability need to be further improved in order to meet the growing demand. Herein, a graphite anode material’s thermo-electrochemical stability was improved by the surface coating of lithium phosphate (Li3PO4; LPO). The graphite anode with a well-dispersed LPO-coating layer (graphite@LPO) demonstrated significant improvement in the cycle and rate performances. The graphite@LPO sample showed a capacity retention of 67.8% after 300 cycles at 60 °C, whereas the pristine graphite anode failed after 225 cycles, confirming the ameliorated thermo-electrochemical stability and cyclability by LPO coating. The improved thermo-electrochemical stability of the graphite@LPO anode was validated by the full-cell tests as well. The performance enhancement by LPO-coating is due to the suppression of the growth of the surface film and charge-transfer resistances during the repeated cycling, as evidenced by the electrochemical impedance spectroscopy analysis.

50

Al-Obaidi, Ahmed Ramadhan, and Jassim Alhamid. "Investigation of the effect of various corrugated pipe configurations on thermo-hydraulic flow and enhancement of heat transfer performance with the development of different correlations." International Journal of Thermal Sciences 176 (June 2022): 107528. http://dx.doi.org/10.1016/j.ijthermalsci.2022.107528.

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