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Processes
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Enhancement of Heat Transfer and Fluid Flow
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Enhancement of Heat Transfer and Fluid Flow

A special issue of Processes (ISSN 2227-9717). This special issue belongs to the section "Energy Systems".

Deadline for manuscript submissions: closed (31 May 2022) | Viewed by 31386

Special Issue Editors

Prof. Dr. Paolo Blecich

E-Mail Website
Guest Editor
Faculty of Engineering, University of Rijeka, 51000 Rijeka, Croatia
Interests: thermodynamics; heat and mass transfer; heat exchangers; energy efficiency; building energy analysis; renewable energy; energy conversion and management
Special Issues, Collections and Topics in MDPI journals
Prof. Dr. Tomislav Mrakovčić

E-Mail Website
Guest Editor
Faculty of Engineering, University of Rijeka, 51000 Rijeka, Croatia
Interests: internal combustion engines; energy and exergy analysis; fuels; marine energy systems; greenhouse gases control
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

The enhancement of heat transfer and fluid flow in existing and emerging engineering applications is rapidly developing. This topic encompasses enhanced heat transfer and fluid flow in natural and forced convection of liquids and gases, conduction and radiation heat transfer as well as boiling and condensation. A variety of enhancement techniques for heat transfer and fluid flow are being researched to improve the thermal and hydraulic performance of heat exchangers, heat pumps, turbomachinery, HVAC&R components, renewable energy systems, internal combustion engines, and energy conversion processes. These enhancement techniques include but are not limited to improved geometries and shapes, extended surfaces, active and passive fluid flow control, microscale and nanoscale heat transfer and fluid flow, nanofluids, and multiphase flow.

This Special Issue is open for original research articles that use experimental, theoretical, or computational approaches to the study of heat transfer and fluid flow enhancement. Review articles about the latest developments and research efforts in this field are also welcome.

Dr. Paolo Blecich
Prof. Dr. Tomislav Mrakovčić
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Processes is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  •  Extended surfaces and improved geometries and shapes
  •  Microscale and nanoscale heat transfer and fluid flow
  •  Nanofluids and fluid additives
  •  Multiphase flow
  •  Active and passive fluid flow control
  •  Experimental, theoretical, and computational analysis
  •  Heat exchangers
  •  Turbomachinery
  •  HVAC&R components
  •  Internal combustion engines
  •  Energy conversion processes

Published Papers (11 papers)

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Research

14 pages, 2074 KiB  
Article
Simulation Study on Mechanical Wear Detection of High-Power Diesel Engine Based on Thermodynamic Coupling
by Jingli Li, Baoqiu Ma, Jianwei Liang and Yu Zhang
Processes 2022, 10(6), 1175; https://0-doi-org.brum.beds.ac.uk/10.3390/pr10061175 - 11 Jun 2022
Viewed by 1186
Abstract
The existing mechanical wear detection methods cannot accurately obtain the state characteristic data of mechanical equipment, resulting in high detection accuracy but low detection efficiency. In order to obtain more ideal results of mechanical wear detection, the mechanical wear detection technology of a [...] Read more.
The existing mechanical wear detection methods cannot accurately obtain the state characteristic data of mechanical equipment, resulting in high detection accuracy but low detection efficiency. In order to obtain more ideal results of mechanical wear detection, the mechanical wear detection technology of a high-power diesel engine based on thermodynamic coupling is designed. Through the coupling of thermodynamics, the thermal stress in the body is solved under the temperature field and corresponding boundary conditions. The state data of mechanical equipment are collected, the wavelet entropy in the state data of mechanical equipment is extracted as the feature of mechanical wear detection, and the least squares support vector machine is used to establish the mechanical wear detection model. The multi-domain unified language modelica is used to model the thermodynamic module and dynamic module of the diesel engine, respectively, to realize the joint simulation of thermodynamics and dynamics, and improve the simulation technology of mechanical wear detection of the high-power diesel engine. Through the simulation and verification test, it is found that the mechanical wear detection time is shorter, the mechanical wear detection efficiency is higher, and it has better practical application value. Full article
(This article belongs to the Special Issue Enhancement of Heat Transfer and Fluid Flow)
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25 pages, 9592 KiB  
Article
1-D Modeling of Two Phase Flow Process in Concentric Annular Heat Pipe and Experimental Investigation
by Ji-Su Lee, Jae-Hyun Ahn, Heui-Il Chae, Hi-Chan Lee and Seok-Ho Rhi
Processes 2022, 10(3), 493; https://0-doi-org.brum.beds.ac.uk/10.3390/pr10030493 - 01 Mar 2022
Viewed by 3832
Abstract
As the heat dissipation of smart devices increases, cutting-edge cooling solutions are becoming increasingly important. The heat pipe is an efficient device that boosts heat transfer and is recommended to reduce thermal management power. In this study, a concentric annular heat pipe (CAHP) [...] Read more.
As the heat dissipation of smart devices increases, cutting-edge cooling solutions are becoming increasingly important. The heat pipe is an efficient device that boosts heat transfer and is recommended to reduce thermal management power. In this study, a concentric annular heat pipe (CAHP) with distilled water as a working fluid is proposed to enhance heat transfer, and experiments and one-dimensional analysis were carried out to predict thermal characteristics and evaluate performance. The CAHP was 90 mm in length, 62 mm in inner diameter, 70 mm in outer diameter, and 0.4 mm in thickness. At the outer surface of the internal CAHP, a two-layer screen mesh wick (500 mesh, Stainless Steel 304) that is 0.34 mm in layer thickness was installed. A ceramic heater (20 mm × 20 mm) was attached to the middle of the outer surface, and the hollow region with 48 fins was cooled by an electric fan. The experiment was carried out with variations in the heat load, the filling ratio of the working fluid, the pitch angle, the roll angle, and the airflow speed, and the one-dimensional analysis was modeled by AMESIM. The experimental results showed that the best thermal resistance of the CAHP was 3.74 °C/W with a supplied heat of 20 W, a pitch angle of −15°, and a Vair of 3 m/s. In addition, the CAHP’s 1-D simulation model using AMESIM was verified through the experimental results. However, although the modeling results according to the inclination angle could not be reflected due to the difficulty of implementing multiple orientation structures in the one-dimensional simulation model, the simulation results were found to be almost consistent with the experimental results. Case studies were conducted to understand the various characteristics of the CAHP using the model, and the optimal volume fraction, the porosity, and the number of layers of the wicks were determined to be 10, 0.345, and 2, respectively. Full article
(This article belongs to the Special Issue Enhancement of Heat Transfer and Fluid Flow)
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29 pages, 1185 KiB  
Article
Heat Transfer Models for Dense Pulverized Particle Jets
by Markus Bösenhofer, Mario Pichler and Michael Harasek
Processes 2022, 10(2), 238; https://0-doi-org.brum.beds.ac.uk/10.3390/pr10020238 - 26 Jan 2022
Cited by 1 | Viewed by 2060
Abstract
Heat transfer is a crucial aspect of thermochemical conversion of pulverized fuels. Over-predicting the heat transfer during heat-up leads to under-estimation of the ignition time, while under-predicting the heat loss during the char conversion leads to an over-estimation of the burnout rates. This [...] Read more.
Heat transfer is a crucial aspect of thermochemical conversion of pulverized fuels. Over-predicting the heat transfer during heat-up leads to under-estimation of the ignition time, while under-predicting the heat loss during the char conversion leads to an over-estimation of the burnout rates. This effect is relevant for dense particle jets injected from dense-phase pneumatic conveying. Heat fluxes characteristic of such dense jets can significantly differ from single particles, although a single, representative particle commonly models them in Euler–Lagrange models. Particle-resolved direct numerical simulations revealed that common representative particles approaches fail to reproduce the dense-jet characteristics. They also confirm that dense clusters behave similar to larger, porous particles, while the single particle characteristic prevails for sparse clusters. Hydrodynamics causes this effect for convective heat transfer since dense clusters deflect the inflowing fluid and shield the center. Reduced view factors cause reduced radiative heat fluxes for dense clusters. Furthermore, convection is less sensitive to cluster shape than radiative heat transfer. New heat transfer models were derived from particle resolved simulations of particle clusters. Heat transfer increases at higher void fractions and vice versa, which is contrary to most existing models. Although derived from regular particle clusters, the new convective heat transfer models reasonably handle random clusters. Contrary, the developed correction for the radiative heat flux over-predicts shading effects for random clusters because of the used cluster shape. In unresolved Euler–Lagrange models, the new heat transfer models can significantly improve dense particle jets’ heat-up or thermochemical conversion modeling. Full article
(This article belongs to the Special Issue Enhancement of Heat Transfer and Fluid Flow)
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20 pages, 37831 KiB  
Article
CFD Analysis of a Large Marine Engine Scavenging Process
by Tomislav Senčić, Vedran Mrzljak, Vedran Medica-Viola and Igor Wolf
Processes 2022, 10(1), 141; https://0-doi-org.brum.beds.ac.uk/10.3390/pr10010141 - 10 Jan 2022
Cited by 7 | Viewed by 2993
Abstract
The scavenging process is an important part of the two-stroke engine operation. Its efficiency affects the global engine performance such as power, fuel consumption, and pollutant emissions. Slow speed marine diesel engines are uniflow scavenged, which implies inlet scavenging ports on the bottom [...] Read more.
The scavenging process is an important part of the two-stroke engine operation. Its efficiency affects the global engine performance such as power, fuel consumption, and pollutant emissions. Slow speed marine diesel engines are uniflow scavenged, which implies inlet scavenging ports on the bottom of the liner and an exhaust valve on the top of the cylinder. A CFD model of such an engine process was developed with the OpenFOAM software tools. A 12-degree sector of the mesh was used corresponding to one of the 30 scavenging ports. A mesh sensitivity test was performed, and the cylinder pressure was compared to experimental data for the analyzed part of the process. The scavenging performances were analyzed for real operation parameters. The influence of the scavenge air pressure and inlet ports geometric orientation was analyzed. The scavenging process is analyzed by means of a passive scalar representing fresh air in the cylinder. Isosurfaces that show the concentration of fresh air were presented. The variation of oxygen and carbon dioxide with time and the axial and angular momentum in the cylinder were calculated. Finally, the scavenging performance for the various operation parameters was evaluated by means of scavenging efficiency, charging efficiency, trapping efficiency, and delivery ratio. It was found that the scavenging efficiency decreases with the engine load due to the shorter time for the process. The scavenging efficiency increases with the pressure difference between the exhaust and scavenging port, and the scavenging efficiency decreases with the increase in the angle of the scavenging ports. It was concluded that smaller angles than the industry standard of 20° could be beneficial to the scavenging efficiency. In the investigation, the charging efficiency ranged from 0.91 to over 0.99, the trapping efficiency ranged from 0.54 to 0.83, the charging efficiency ranged from 0.78 to 0.92, and the delivery ratio ranged from 1.21 to 2.03. Full article
(This article belongs to the Special Issue Enhancement of Heat Transfer and Fluid Flow)
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13 pages, 4439 KiB  
Article
Effect of Steam Flow Rate and Storage Period of Superhydrophobic-Coated Surfaces on Condensation Heat Flux and Wettability
by Nataliia Fedorova, Christian Lindner, Lucia Helena Prado, Vojislav Jovicic, Ana Zbogar-Rasic, Sannakaisa Virtanen and Antonio Delgado
Processes 2021, 9(11), 1958; https://0-doi-org.brum.beds.ac.uk/10.3390/pr9111958 - 02 Nov 2021
Cited by 1 | Viewed by 1486
Abstract
The jumping-droplet phenomenon occurring on superhydrophobic (SHPhob) surfaces under special conditions may be beneficial for numerous systems using condensation, due to the reported increased heat transfer coefficients. One technique to create a SHPhob surface is coating, which can be applied to larger areas [...] Read more.
The jumping-droplet phenomenon occurring on superhydrophobic (SHPhob) surfaces under special conditions may be beneficial for numerous systems using condensation, due to the reported increased heat transfer coefficients. One technique to create a SHPhob surface is coating, which can be applied to larger areas of existing elements. However, challenges are associated with coating stability and the realization of continuous dropwise condensation. This research examined the condensation of steam at different flow rates (2, 4 and 6 g/min) and its influence on heat flux and water contact angles on the SHPhob spray-coated aluminum samples. Special emphasis on the impact of time was addressed through a series of one and five-hour condensation experiments on the samples with different storage periods (coated either one year ago or shortly before testing). Over the experimental series at a higher steam flow rate (6 g/min), heat flux decreased by 20% through the old-coated samples and water contact angles transferred from the superhydrophobic (147°) to hydrophobic (125°) region. This can be attributed to the joint effects of the partial coating washout and the adsorption of the condensed water within the porous structures of the coating during steam condensation. The new-coated samples could sustain more than fifty hours of condensation, keeping the same heat fluxes and SHPhob characteristics. Full article
(This article belongs to the Special Issue Enhancement of Heat Transfer and Fluid Flow)
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13 pages, 3544 KiB  
Article
Heat Transfer Enhancement in Gravity Heat Pipes Using AAO Nanostructure Generated on Condenser Section Inner Surface
by Chun-Ching Kuo and Huei Chu Weng
Processes 2021, 9(10), 1827; https://0-doi-org.brum.beds.ac.uk/10.3390/pr9101827 - 14 Oct 2021
Cited by 1 | Viewed by 1301
Abstract
This study mainly focuses on the influence of anodic aluminum oxide (AAO) nanostructure generated on condenser section inner surface on the heat transfer performance of gravity heat pipes. AAO nanotubes were first grown by anodizing the inner wall surface of the condenser section [...] Read more.
This study mainly focuses on the influence of anodic aluminum oxide (AAO) nanostructure generated on condenser section inner surface on the heat transfer performance of gravity heat pipes. AAO nanotubes were first grown by anodizing the inner wall surface of the condenser section of aluminum alloy gravity heat pipes through different anodizing voltages and treatment times. The nanostructure effect on the temperature distribution and overall thermal resistance was then investigated by using a thermal performance test system under different input heat powers. The experimental results showed that the generation of AAO nanostructure on the inner surface significantly enhances heat transfer performance; that is, the temperature difference between the evaporator and condenser sections and overall thermal resistance are reduced. Such an effect can be more significant in the case of a lower heat source. The percentage decreases in temperature difference and overall thermal resistance can be reduced by up to 58.83% and 58.79%, respectively, compared to the unprocessed heat pipe. Full article
(This article belongs to the Special Issue Enhancement of Heat Transfer and Fluid Flow)
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16 pages, 4887 KiB  
Article
Higher Order Accurate Transient Numerical Model to Evaluate the Natural Convection Heat Transfer in Flat Plate Solar Collector
by Nagesh Babu Balam, Tabish Alam, Akhilesh Gupta and Paolo Blecich
Processes 2021, 9(9), 1508; https://0-doi-org.brum.beds.ac.uk/10.3390/pr9091508 - 26 Aug 2021
Cited by 2 | Viewed by 2126
Abstract
The natural convection flow in the air gap between the absorber plate and glass cover of the flat plate solar collectors is predominantly evaluated based on the lumped capacitance method, which does not consider the spatial temperature gradients. With the recent advancements in [...] Read more.
The natural convection flow in the air gap between the absorber plate and glass cover of the flat plate solar collectors is predominantly evaluated based on the lumped capacitance method, which does not consider the spatial temperature gradients. With the recent advancements in the field of computational fluid dynamics, it became possible to study the natural convection heat transfer in the air gap of solar collectors with spatially resolved temperature gradients in the laminar regime. However, due to the relatively large temperature gradient in this air gap, the natural convection heat transfer lies in either the transitional regime or in the turbulent regime. This requires a very high grid density and a large convergence time for existing CFD methods. Higher order numerical methods are found to be effective for resolving turbulent flow phenomenon. Here we develop a non-dimensional transient numerical model for resolving the turbulent natural convection heat transfer in the air gap of a flat plate solar collector, which is fourth order accurate in both spatial and temporal domains. The developed model is validated against benchmark results available in the literature. An error of less than 5% is observed for the top heat loss coefficient parameter of the flat plate solar collector. Transient flow characteristics and various stages of natural convection flow development have been discussed. In addition, it was observed that the occurrence of flow mode transitions have a significant effect on the overall natural convection heat transfer. Full article
(This article belongs to the Special Issue Enhancement of Heat Transfer and Fluid Flow)
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15 pages, 12206 KiB  
Article
Effects of Fin Arrangements on Thermal Hydraulic Performance of Supercritical Nitrogen in Printed Circuit Heat Exchanger
by Shan Yang, Zhongchao Zhao, Yong Zhang, Zhengchao Chen and Min Yang
Processes 2021, 9(5), 861; https://0-doi-org.brum.beds.ac.uk/10.3390/pr9050861 - 13 May 2021
Cited by 8 | Viewed by 2523
Abstract
The printed circuit heat exchanger (PCHE) with discontinuous fins is a novel type of compact and highly efficient plate heat exchanger, which has superior thermal hydraulic performance. The morphology and characteristics of the flow channel greatly affect the performance of the PCHE. The [...] Read more.
The printed circuit heat exchanger (PCHE) with discontinuous fins is a novel type of compact and highly efficient plate heat exchanger, which has superior thermal hydraulic performance. The morphology and characteristics of the flow channel greatly affect the performance of the PCHE. The discontinuous airfoil fins are used in PCHE channel design because they can affect the flow and heat transfer by increasing the heat transfer area and the disturbance in the channel. In this paper, the effects of different staggered distance (Ls) and transverse distance (Lv) of airfoil fin arrangements on the heat transfer and flow of supercritical nitrogen in the PCHE are numerically simulated using ANSYS Fluent. Simulation results and subsequent analysis show that the appropriate decrease in Ls and reduction in Lv between the two rows of fins can improve the convective heat transfer of the PCHE. A fully staggered arrangement of fins (Ls = 1.2) and an appropriate increase in the Lv can mitigate pressure drop. The comprehensive performance of different channel geometries is compared by the performance evaluation criteria (PEC) in this study. It is shown that considering flow resistance and heat transfer, the comprehensive heat transfer performance can be enhanced by properly increasing the staggered distance and the vertical distance between fins. When Ls = 1.2 mm and Lv = 1.25 mm, the PEC value of the staggered channel is the highest, which is 11.6% higher than that of the parallel channel on average. Full article
(This article belongs to the Special Issue Enhancement of Heat Transfer and Fluid Flow)
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15 pages, 3932 KiB  
Article
Flow and Heat Transfer Property of Oldroyd-B-Fluid-Based Nanofluids Containing Cylindrical Particles in a Pipe
by Wenqian Lin, Peijie Zhang and Jianzhong Lin
Processes 2021, 9(4), 647; https://0-doi-org.brum.beds.ac.uk/10.3390/pr9040647 - 08 Apr 2021
Cited by 1 | Viewed by 1985
Abstract
Flow and heat transfer property of Oldroyd-B-fluid-based nanofluids containing cylindrical particles are studied in a pipe with circular cross-section in the range of Reynolds number (Re) from 100 to 2000, Weissenberg number (We) from 0.1 to 2, particle aspect ratio (β) [...] Read more.
Flow and heat transfer property of Oldroyd-B-fluid-based nanofluids containing cylindrical particles are studied in a pipe with circular cross-section in the range of Reynolds number (Re) from 100 to 2000, Weissenberg number (We) from 0.1 to 2, particle aspect ratio (β) from 2 to 16 and particle volume concentration (Φ) from 0.1% to 2.5%. The motion equation of Oldroyd-B fluid with particles, the equation for probability density function of particle orientation and convection-diffusion equation for particles are solved numerically. The numerical method used in the simulation is validated by comparing with the available results. The effects of Re, We, β and Φ on the friction factor (f), Nusselt number (Nu) and ratio of energy performance evaluation criterion (PECt/PECf) for Oldroyd-B-fluid-based nanofluids to that for Oldroyd-B fluids are discussed. The results showed that the values of f and Nu of Oldroyd-B-fluid-based nanofluids are larger than that of water-based nanofluids and that of pure Oldroyd-B fluids. The values of f increase with increasing Re, We and Φ, but with decreasing β. The values of Nu and PECt/PECf are enhanced with increasing Re, We, β and Φ. The increase of f is larger than that of Nu at lower Re, but is less than that of Nu at higher Re. It is more effective to use Oldroyd-B-fluid-based nanofluids with cylindrical nanoparticles to improve the heat transfer at the conditions of higher Re, We, β and Φ. Finally, the correlation formula of PECt/PECf as a function of Re, We, β and Φ is derived. Full article
(This article belongs to the Special Issue Enhancement of Heat Transfer and Fluid Flow)
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13 pages, 4646 KiB  
Article
Analysis of Global Warming’s Influence on the Dimensioning of Borehole Heat Exchangers at a Climate-Exposed Site
by Antonín Kunz, Martin Klempa, Petr Bujok and Dawid Piotrowski
Processes 2021, 9(3), 501; https://0-doi-org.brum.beds.ac.uk/10.3390/pr9030501 - 10 Mar 2021
Cited by 1 | Viewed by 1586
Abstract
A borehole heat exchanger (BHE) presents the most reliable source of geothermal energy for any object where the heat pump system is to be installed. The main objective of BHE optimization in a specific rock massive and for calculated heat consumption is to [...] Read more.
A borehole heat exchanger (BHE) presents the most reliable source of geothermal energy for any object where the heat pump system is to be installed. The main objective of BHE optimization in a specific rock massive and for calculated heat consumption is to design a BHE with proper capacity and sustainable performance. One of the most important inputs for the preparation of such a model is the average outer air temperature on the site during the year. While the properties of the local rock massive are from the heat project lifetime view (tens of years) stable, the local average outer temperature fluctuates according to global climate changes. This article presents a study of the impact of climate changes on the dimensioning process of a BHE and consequently on its performance using data from a real installation at a highly climate-exposed site in the Czech Republic. During the dimensioning of a BHE, this study could help to better quantify the objective risks that result from climate changes. However, the results of this study show that the currently calculated impact of an increase in outer temperature is not crucial, but it is advisable to take this new fact into account during the design and dimensioning process, especially for large installations. To study the ground in terms of usable energy potential at climate-exposed locations properly, the available data were critically analyzed and the results were then synthesized in an appropriate way for the needs of the data simulations. Full article
(This article belongs to the Special Issue Enhancement of Heat Transfer and Fluid Flow)
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18 pages, 3945 KiB  
Article
An Investigation of Heat Transfer Performance in an Agitated Vessel
by Maha Mahir, Anas El Maakoul, Ismail Khay, Said Saadeddine and Mohamed Bakhouya
Processes 2021, 9(3), 468; https://0-doi-org.brum.beds.ac.uk/10.3390/pr9030468 - 05 Mar 2021
Cited by 9 | Viewed by 8487
Abstract
Agitated vessels (or mechanically stirred reactors) are heat exchange devices that are most widely used in many chemical and biochemical process industries, such as anaerobic digestion process. The mixing and heat transfer performances in these vessels are of crucial importance for increasing the [...] Read more.
Agitated vessels (or mechanically stirred reactors) are heat exchange devices that are most widely used in many chemical and biochemical process industries, such as anaerobic digestion process. The mixing and heat transfer performances in these vessels are of crucial importance for increasing the energy efficiency in both batch and continuous processes. In this paper, a series of experiments were conducted to investigate heat transfer performance in agitated vessels for various configurations. In fact, this study examines the effects of heat transfer geometry (wall jacket and helical coils), heating power, and stirring speed, on the heating performance of two stirred fluids—water alone and a mixture of water and food waste. The experiments were conducted using a jacketed insulation tank with a helical coil and a propeller agitator. In each experiment, a transient method, based on measuring the temperature dependency on time, and solving the unsteady enthalpy balance, was used to determine the overall heat transfer coefficients between the agitated fluid and the heating surface. Finally, an extensive analysis of the reduced data was conducted based on temperature, heating time, heat transfer rate, heat transfer coefficient, and thermal resistance. The main finding was that the presence of food waste in agitated vessels reduces the heat rate of the agitated fluid with an average of 18.13% and 49.51%, respectively, for the case of JHX and CHX, and creates additional fouling, which further limits the heat transfer. Full article
(This article belongs to the Special Issue Enhancement of Heat Transfer and Fluid Flow)
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