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In the present publication, a validation by means of the dimensionless ratios between the calculation of heat transfer coefficients and the experiment on an isothermally rotating device is performed. The investigations provide important insights into the design of internal cooling channels of turbine blades. It is shown that forced convection is dominant. For this reason, an isothermally rotating tube is chosen for the validation. This leads to further precision of the validation, since the buoyancy effect (described by the Archimedes-Number of rotations, Ar≈0) in the axial direction is eliminated. The variation to determine the dimensionless heat transfer Nu-Number takes place in the ratio range Reynolds (Re)-Numbers=8,500 to 52,000, Rotational (Ro)-Numbers=0 to 0,2 and at a Prandtl (Pr)-Number of 2.5. In order to keep the isothermal conditions and to get an extremely high local resolution of the Nu-Numbers, experimental investigations were carried out with the Heat- and Mass-Transfer-Analogy. This is possible because the differential equations (energy / concentration) are the same at small Mach-Numbers (Ma ≈0) and the Stefan-current is negligible. By analogy with the Nu-Number, a dimensionless mass transfer Sh-Number could be chosen. The dimensionless Pr-Number then corresponds to the dimensionless Schmidt (Sc) -Number. Local Sh-Numbers (and thus the Nu-Numbers) could be determined with high resolution via the layer thickness loss of the sublimate (naphthalene /air system, Sc =2.5). The local Sh-Number and thus the Nu-Number are known. The Nu, Sh results are determined as a function of the Re-and Ro-Number (related to the pipe diameter), in the pipe circumferential direction φ and dimensionless length x/d (with and without hydraulic flow) for the Pr, Sc-number and compared with the numerical calculations and the correlation. It could be shown that the use of a sublimate results in the following advantages for the validation: no vagrant heat flows in the wall, exact compliance with the boundary condition, pipe wall temperature=const (since wall concentration is constant) and Ar≈0. Thus, for the numerical investigation (with Pr, Sc=2.5), the boundary conditions could be accurately reproduced and compared with the experimental results and correlation. The numerical flow problem was solved using the steady-state Reynolds-averaged Navier-Stokes (RANS) equations. For the closure problem, the Boussinesq approximation was used. The turbulent eddy viscosity of the Boussinesq approximation was calculated using turbulence models (Menter-SST model and the SST transition model). The SST-turbulence model was shown to be a very good fit. The experimental results including the laminar turbulent transition could be reproduced very well with a high precision. A high technical importance for the design of turbine cooling systems could be shown. [ABSTRACT FROM AUTHOR]

Experimental studies to determine the average heat transfer coefficient (hav) and frictional pressure gradient (ΔPF/L) of R-513A flowing through a horizontal smooth tube during evaporation are investigated. The experimental setup comprises a double-tube heat exchanger with supplied water circulating inside the annulus in the opposite direction. The average heat transfer coefficient ratio (hav,513A/hav,134a) and frictional pressure gradient ratio ((ΔPF/L)513A/((ΔPF/L)134a) of R-513A and R-134a were compared in this study. The experimental results show hav and ΔPF/L obtained from R-513A are about 0.96 and 0.95 times lower than R-134a, respectively. For R-513A, the hav is lower due to a decreased convective effect, whereas the lower ΔPF/L is due to decreased flow resistance. The Nusselt number (Nu) is higher than R-134a, whereas the two-phase friction factor (fTP) is slightly higher. [ABSTRACT FROM AUTHOR]

We investigated the natural convective heat transfer characteristics within a solar power plant having a built-in aluminium metallic porous block and by using MWCNT-Fe3O4/water hybrid nanofluid. The Darcy-Brinkmann-Forchheimer model is used to describe the porous media flow field as well as the energy equation. When a metallic porous block is integrated to the plant, the average Nusselt number becomes significantly higher and increases with increasing Darcy numbers. The use of a hybrid nanofluid causes higher heat transfer rate compared to a pure fluid. Inferences obtained from this analysis are expected to provide a design basis of a modern solar plant intended for augmented energy recovery. [ABSTRACT FROM AUTHOR]

The current research is concerned with unsteady boundary lamina flow in a porous material adjacent to a stretching-sheet, as well as a related heat transfer problem. The controlling PDEs and ODEs boundary layer for flow and for temperature by distribution were reduced using the similarity transformation method. These equations are solved numerically. MATLAB was used to conduct a numerical analysis of the influence of several Key parameters on rate distribution, distribution of temperature, pore, and friction of the skin, and rate of heat transformation on the Stretch sheet. [ABSTRACT FROM AUTHOR]

The current research focuses on the heterogeneity of fluid when it is allowed to flow over two parallel porous plates, as well as considering the flow to be viscous oscillatory in the presence of an angled magnetic field, as well as a radiative heat flux and heat source. The fluid is hypothesized to have an extremely low electrical conductivity, and the electromagnetic forces are measured in nanometers. Analytical solutions are provided for the consequences of various elements influencing the problem on velocity and temperature profiles, local skin friction coefficient, and local Nusselt number. [ABSTRACT FROM AUTHOR]

The use of solar air heaters for building in European countries is important as it helps in making the rooms hot during the winter. Due to the low energy conversion efficiency of passive solar air heaters, a constant flow of air is required. This flow can be achieved with the help of an airflow pump which is driven by electricity. The alternate source for providing the electricity to pump is a thermoelectric generator that generates the electricity with the help of solar radiation. The positioning of the thermoelectric generator is a new task that is investigated in the present work, two configurations, one on the placement of the thermoelectric generator over the absorber plate and the other at the house walls are investigated. A simulation model is developed in COMSOL Multiphysics 5.5 with the measurement of the temperature of thermoelectric material at different positions calculated. The results indicated that the placement of a thermo-electric generator at the absorber plate generates a temperature of 325 K which is more in comparison to when placed over the walls i.e., 312 K. [ABSTRACT FROM AUTHOR]

In the Material Extrusion process (MEX) the main limiting factor is the printing speed, as is the case in many other Additive Manufacturing (AM) processes. In order to enhance the printing speed, systematic experimental investigations are necessary to understand the material dependent processes in the nozzle. In MEX, the filament partially melts inside of a heated hot end and the flow is induced by the feeding force of the solid filament part, acting as a stamp on the molten polymer. In a previous work by Wolff et al., Computational Fluid Dynamics (CFD) simulations of the MEX hot end were performed based on experimental studies using the experimental maximum feeding rate as the upper boundary condition. It was depicted that the numerical model can accurately predict the feeding force and can represent the change between process windows as the speed increases. To calculate the maximum feeding rate, the heat transfer conditions in the hot end must be considered. In this study, various techniques for determining the upper limit of feeding rates are evaluated for acrylonitrile-butadiene styrene (ABS) and polypropylene (PP) materials with different nozzle geometries. When the solid filament cone reaches the contraction zone with glass transition respectively melting temperature at maximum feeding rates, the results match well with the experimental data. Ultimately, it is possible to quantify the heat transfer in the nozzle through numerical modelling of the filament feeding force. [ABSTRACT FROM AUTHOR]

Pipes in heat exchanger systems are usually made of metallic materials to achieve a high level of thermal conductivity and thus high efficiency. However, substitution with polymer materials has a great potential. Plastics save weight, can be produced at lower cost and emissions, and are ideal for use in corrosive or chemically aggressive environments, where most metals fail. The challenge, however, is their much lower thermal conductivity in comparison. To reduce this disadvantage, fillers are used to transport thermal energy through the less conductive polymer matrix. In fact, high filler ratios are required to achieve an acceptable level of thermal conductivity for heat exchanger systems. However, these high filler ratios have a significant impact on the material properties of the polymer, such as the flexibility, which is drastically reduced. The result is a brittle material with limited suitability for use in heat exchanger systems. This paper describes a novel approach to effectively increase the thermal conductivity of polymer materials by optimizing the orientation of anisotropic filler particles by die design. Standard pipe extrusion dies result in continuous shear forces in the direction of extrusion. Accordingly, the resulting filler network has a higher thermal conductivity in the axial direction of the pipe than radially through the pipe wall. However, radial heat transfer is essential in pipe heat exchanger systems. To improve this, various die designs for targeted radial alignment of filler particles are discussed in this paper. Furthermore, the potential for improvement of the die designs is investigated. So far, the most efficient die design achieves an increase in thermal conductivity of up to 74 % compared to a standard pipe extrusion die. [ABSTRACT FROM AUTHOR]

In this work, the initial and boundary problem is consider for the the process of heat propagation in a body consisting of two plates with different thermo-physical characteristics. Finite difference method used to solve the problem. Two regularizing procedures were used to obtain stable solutions. It is shown that with increasing distance between the point of measurement of the "initial data" and the boundary of the region, disturbance of the initial data, the stability of the solution deteriorates. [ABSTRACT FROM AUTHOR]

Due to the unpredictability of renewable energy, stable storage systems are an essential part of combating global warming. The foundation for the development of more compact and simple-to-fabricate storage components has been laid by investigations into the latent heat transfer that occurs in almost all isothermal situations within phase change material (PCM) storage units. In this study, a horizontal triplex square channel thermal storage unit (TSCTSU) with internal and external longitudinal fins utilizing a PCM with a melting temperature within a range of 38.15 to 42.15 °C was constructed for evaluation as a device for storing power. The effect of mass flow rates and heat transfer fluid (HTF) inlet temperatures on PCM melting and charging under steady and non-steady were thus numerically investigated and, according to the results, the PCM melting process is influenced more significantly by the HTF inlet temperature than by the HTF mass flow rate. Fin length also significantly affected melting time, however, with this time decreasing as fin length increased: as an example, for fin lengths of 42 mm and 47.6 mm, the liquid fraction melting durations were 38 and 34 min, respectively. [ABSTRACT FROM AUTHOR]

This work presents the use of an experimental coupled cross flow heat exchanger and underground water system to evaluate the use of this system for cooling animal farms under industrial conditions. The experiments were performed between 4 April and 12 June 2020, during the summer. The water flow rate in the test section was regulated between 10 to 15 litres per minute, while the air velocity varied from 4.5 to 10.5 m/s. The results indicate that the system can be used in areas such as Karbala city in Iraq for the cooling of farm buildings. During the test period, the maximum heat transferred to the ground was approximately 0.9 kW, with a mass flow rate of 0.16 kg/s. The maximum average temperature difference between the inlet water and ambient temperature was approximately 15 °C, while the air temperature inside the modular room decreased by about 12 °C. According to these results, direct ground cooling is a suitable method for the cost-effective cooling of buildings by circulating cold water through a heat exchanger. [ABSTRACT FROM AUTHOR]

Water cooling in the circulating water supply systems is common in different industries. A closed-circuit cooling tower is developed with indirect gas-liquid contact by means of an internal tube heat exchanger with an inline tube arrangement. The purpose of the work is a numerical study of the thermal characteristics of the developed cooling tower. The heat transfer coefficients on the different tubes of the heat exchanger were found to vary significantly depending on the mean air velocity in the cooling tower unit and the location of the tubes. The obtained results of numerical calculation were verified by comparison with an analytical solution based on the various criterion equations describing the transverse air flow around a tube bundle with a corridor arrangement of tubes. [ABSTRACT FROM AUTHOR]

The work proposes a multiscale digital model of heat and mass transfer thermally activated power technological processes occurring in the bath of an ore-thermal furnace, considering the scale levels of the working space, such as the charge area, the intensive melting zone, the carbon zone or reaction area and the lower slag area. The results of an analysis for the intensification of heterogeneous reduction and dissolution reactions with consideration for hydrodynamic and mass transfer aspects, as well as shielding the surface of the reaction area when gas-phase products appear, are presented to determine the modes that ensure the optimal functioning of technological reactors-ore-thermal furnaces. [ABSTRACT FROM AUTHOR]

This paper explores the characteristics of heterogeneous reactions occurring during the release of gas bubbles upon contact with a solid reducing agent. The investigation considers the hydrodynamics and heat/mass transfer features involved in the reduction reaction within the coke zone of an ore-thermal furnace. The complexity arises from the presence of a gas phase bubbling through the melt. The conditions created by the formation of bubbles enhance mixing, thereby activating chemical and metallurgical reduction processes. A fundamental element of the reaction involves the reagent actively diffusing due to vigorous mixing, causing a transition of the reduction process into the kinetic domain. Key considerations at this juncture encompass the temperature within the reaction zone and the concentration of the reagent. The interplay of the reduction reaction and the creation of gas bubbles affects the development of convective currents, with their formation being influenced by both temperature and reagent concentration. [ABSTRACT FROM AUTHOR]

Experimental and calculated data are presented on the thermal fluxes of arc radiation on the surface and in the depth of the bath, which differ by no more than 5-8%, which confirms the compliance of the laws of thermal radiation of gas volumes with real heat transfer processes in arc steelmaking furnaces (ASF). The calculation of the heat exchange of arcs in the ASF-100 bath has been performed. It is established that in the spherical segments under the arcs in the metal bath, a unique physical phenomenon occurs of converting a powerful heat flux of arc radiation into a powerful intense convective heat flux and a thermal conductivity flow in a liquid metal bath and slag. [ABSTRACT FROM AUTHOR]

This paper presents the desired characteristics of adsorbent and adsorbate in adsorption cooling system. The development of competitive market ready adsorption chiller is hindered by the physics of the adsorbent-adsorbate pairs, the main component of this cooling system. A breakthrough is required to produce adsorbent-adsorbate pairs with superior characteristics. The adsorbent-adsorbate pair must have low heat of adsorption compared to the latent heat of vaporization of refrigerant. The adsorbent uptake must be sensitive to its temperature, to reduce energy usage for sensible heating during transition from adsorption to desorption phase. An increase on the rate of adsorption and desorption must be accompanied by increase in rate of heat transfer to make sure optimum performance can be achieved. For a quick assessment on performance of adsorbent, refrigerant and heat exchange surface, adsorption calorimeter could be used. [ABSTRACT FROM AUTHOR]

The heat pipe is a device that can transfer heat very effectively and passively. Heat pipes are widely used as thermal management tools in various fields, including nuclear reactors. Although heat pipes can have various geometries and shapes, heat pipes consist of three parts: the evaporator, adiabatic, and condenser. The adiabatic will pass the working fluid in gas from the evaporator to the condenser and pass the working fluid in a liquid from the condenser to the evaporator. There are very limited studies on the effect of adiabatic length on thermal performance. Therefore, research has been carried out on the effect of adiabatic length for heat pipes that have a fixed evaporator and condenser. The research was conducted by numerical simulation on a straight wick-less heat pipe using the RELAP5 computer program. The heat pipe is made of a tube of 1-inch stainless steel, and the working fluid is water. The evaporator and condenser sections have the same length of 50 cm, while the adiabatic sections have variations of 10, 20, 30, 40, 50, 100, 150, and 200 cm. The heat pipe is placed on a heat source of atmospheric water at 80 ○C as well as saturated steam with temperature variations from 80 to 120 ○C. The heat sink is cooling water at a temperature of 29 ○C. The study results show that the thermal performance of the heat pipe is proportional to the adiabatic length when the heat source temperature is much greater than 110 ○C and vice versa when the heat source temperature is much lower than 110 ○C. The adiabatic length does not affect the performance of the heat pipe when the heat source temperature is around 110○C. However, the increase or decrease in heat transfer capability is minimal, so it can be concluded that the adiabatic length has little effect on the thermal performance of the wick-less straight heat pipe. [ABSTRACT FROM AUTHOR]

The main focus of this research is the characterization of the thermal conductivity of pineapple fibre, hempe fibre, and luffa fibre. These three fibres will be used as cooling pads for indirect evaporative cooling with an added heat pipe as a heat exchanger. The characterization of the thermal conductivity of pineapple fibre, hempe fibre, and luffa fibre was investigated experimentally by using a thermoelectric-based thermal conductivity apparatus. The principle of this tool is to make a temperature difference between the two ends of the material. One end is given the heat, while the other end is maintained its temperature (35°C, 40°C, 45°C, 50°C) by peltier cooler. The result shows that the highest thermal conductivity value for all samples achieved at 35 °C. At 35 °C, the thermal conductivity ofhempe fibre is 0.2297 W/mK, luffa fibre is 0.0459 W/mK and pineapple fibre is 0.1746 W/mK. So that it is obtained that the cooling pad in hempe fibre transfers heat greater than that of luffa fibre and pineapple fibre. [ABSTRACT FROM AUTHOR]

The goal of the current work is to better understand how heat transmission originating from a hot, electrically conductive fluid across a moving surface is affected by radiation and melting. The flow problem is converted into linked nonlinear ordinary differential equations by means of the relevant transformations. In the early stage, momentum equation is linearized using Bellman technique of quasi linearization and later Finite difference scheme is utilized to solve numerically. The impacts of different flow parameters are depicted graphically using representative data for velocity and temperature profiles. The momentum boundary layer is influenced by moving parameters to grow. Melting has the effect of lowering the fluid's temperature in the boundary layer. [ABSTRACT FROM AUTHOR]

The huge peatland areas of around 21 Mha in Indonesia have the potential to be a future fuel alternative. Linear with that purpose, exploring the physical and chemical properties is critical for understanding its fuel's potential. This work presents the particular investigations on peat fuel's potential related to the physical characteristics such as moisture, volatile matter, fixed carbon, and ash contents, as well as its heating value. The chemical properties are also fundamental due to they determine various aspects of the fuel in practice, such as the energy content and the formation of the slag deposits in the heat transfer apparatus. For that intent, the peat sample was sun-dried for 8 hours and subsequently heated in an oven at 90 oC for 6 hours. The proximate analysis has been performed, and the results show that peat has the respective contents of volatile matter, fixed carbon, and ash; those are 59.4, 40.3, and 0.3 (wt%, dry basis). It has a higher heating value of 5731 kJ/kg (23.98 MJ/kg). The ultimate analysis revealed that the peat sample has high fuel potential as its carbon content reaches 65.28 (wt%, dry basis), whereas it has low undesirable contents of nitrogen and sulfur, those are 0.74 and 0.22 (wt%, dry basis), respectively. These results provide the data for considering the peat application in the industrial furnace for energy generation. [ABSTRACT FROM AUTHOR]

Mathematical modeling of these combustion processes with the possibility of evaluating the effectiveness of these measures will make it possible to develop optimal operating modes for power plants and develop new technical solutions to reduce pollutant emissions. One of the widely used methods for intensifying energy exchange (mass transfer, heat transfer, etc.) is flow swirling, i.e. message to the flow of multidimensional motion. In the course of the study, dependencies were studied and patterns of low-emission combustion were revealed when using such fuel combinations as mixtures of methane and air and methane and hydrogen. [ABSTRACT FROM AUTHOR]

A cementitious composite carefully designed and mixed using aggregates, cement and waste materials forms a green concrete, providing potential for saving the environment, especially by reducing the carbon consumption in the construction industry. The reliable design of green cementitious composites' thermal conductivity leads to significant energy savings in residential buildings, especially when used as exterior or interior walls. This preliminary study briefly describes a concept of mathematical modeling of green concrete heat transfer since an effective solution to the problem will not only improve the energy saving inside the residential but also increase the efficiency in heat-protection of the structures. The study aims to generate a mathematical model to simulate the thermal properties into a computational model to understand the model behaviour under constant and elevated temperature considering steady-state and transient-state solutions. A two-dimensional thermal model is created first then the thermal properties such as thermal conductivity, mass density, and specific heats are assigned into the model. Seven variables to express the thermal conductivity of concrete are adopted in this study based on previous research. The analysis is then continued by specifying a heat source within two model geometries, i.e. a solid model and a model with cavity. The heat flux is also assigned to estimate the heat exchange between the boundaries. The model is then analyzed, the mathematical model is solved to generate the results of temperature, gradient, and heat rates as well as heat fluxes. This study enables the characterization of thermal transfer and distribution on a green concrete model to be used as approximations in predicting the trends related to thermal properties of a green cementitious composite. [ABSTRACT FROM AUTHOR]

In double-pipe type heat exchangers, the process parameters controlled by an interacting unit using a computer are concentrated in this study. Controlling the process parameter through a computer involves changing the hot water's temperature before it enters the heat exchanger using a solid-state relay. At various flow rates, the effectiveness and heat transfer rate under co-current and counter-current flow has been analysed in this research. To monitor and manage the process, the controller is linked to the computer through USB. Hardware and user-friendly software will be provided in order to conduct various experiments. The outputs obtained by conducting experiments are optimized by using an Artificial neural network. [ABSTRACT FROM AUTHOR]

Layer dryers have not received wide practical application due to the unsatisfactory operation of transport devices and the uneven drying of cotton over the thickness of the layer due to the use of high temperatures. These issues are solved with the application of drying under the influence of infrared radiation on the basis of functional ceramics. However, at the same time, the issue of providing the necessary thickness of raw cotton during layer-by-layer drying remains unresolved. The article obtained formulas for calculating the main parameters of an infrared dryer, developed patterns for drying raw cotton, established relationships showing the processes of heat transfer between radiation and raw materials. [ABSTRACT FROM AUTHOR]

In the present paper the steady two-dimensional MHD viscous flow through a heated two region vertical channel with the occurrence of chemical reaction and radiation has been considered. It has been assumed that the channel contains two regions, one is clear region and other is occupied with porous material. Channel boundaries are set on fixed distance but temperature and concentration of fluid at boundaries are different. The governing equations of the velocity, temperature and mass transfer are derived, and their closed-form results are also obtained. With the effect of radiation, Reynolds number and chemical reaction coefficient, velocity can be slower. The temperature of the fluid can be reduced in both regions by using thermal radiation and increasing thermal conductivity ratio. In addition, shear stress, rate of heat transfer and rate of mass transfer are also calculated for pertained flow constraints. The current problem is also very useful in many areas of geothermal engineering. [ABSTRACT FROM AUTHOR]

The impact of various types of G-jitter on the stability of Oldroyd-B nano-liquid filled in Hele-Shaw cell are investigated in this study. The Oldroyd-B liquid model is significant because of its many applications, including the production of plastic sheets, biological solution pant tars glues, and so on. In the present paper, we observed the Nusselt number on heat transfer for fluid and particle phases and mass transportation for non-linear stability exploration. Both Mathematica NDSolve and RKF-45 methods are used to analyze heat/mass transportation in the region, with the result that they both yield exactly the same heat/mass transportation rate. Consequently, the RKF-45 method has verified that all Mathematica NDSolve solutions are converging. In heat and mass transfer, the Deborah number, retardation parameter, G-jitter, and H-S number all play significant roles. Heat/mass transportation in the region is improved by increasing the amount of the Deborah number, while raises the Hele-Shaw number reduces heat and mass transportation in the region. As the retardation parameter is increased, the heat and mass transportation in the system reduces. [ABSTRACT FROM AUTHOR]

Solar energy is one of the most widely used renewable energy sources. Various collectors were made, tested, and refined to perform in various temperature ranges. The parabolic trough solar collectors (PTC) are the most frequent in steam production and heat process applications. The receiver tube is the heating element and a crucial device (PTC) component. Many studies have focused on improving the thermal efficiency of receiver tubes. A detailed evaluation of the experimental and numerical investigations carried out to improve heat transmission in receiver tubes in four different ways. 1. Use to reduce heat loss (glass cover, selective coating, and evacuated tube) 2. They increase the heat transfer coefficient by using (turbulent flow, Nanofluid, and different gaseous). 3. Increase the surface area of heat transmission using (fins, porous material, surface modification). 4. Combine two or more of these methods. The aims of the current review papers is to improve heat transfer in the receiver tube and reduce heat loss, resulting in improved heat transfer to the thermal fluid. [ABSTRACT FROM AUTHOR]

Spray drying process is considered as a conventional method that is extensively used to convert food product to powder form. It offers a lot of benefit including continuous process, rapid evaporation and industrial viable. But spray drying also expose to various disadvantages such as losses due to the particle's deposition on the drying walls. The understanding on the flow behaviors in the drying chamber of spray drying are important for the strategy to reduce the powder losses during this process. Therefore, in this study, the simulation of flow behavior in the drying chamber was conducted using computational fluid dynamic (CFD). The 2D and 3D was conducted to tested for the most accurate model to represent the process. Discrete phase model (DPM) was used to describe the atomization of the protein particles. The convective terms of the continuous phase equations for several equation and schemes are conducted using ANSYS FLUENT R19.1. Based on the CFD simulation, an uneven velocity distribution between 0.00121 to 3.82 m/s is observed on various zone of the drying chamber which causing the inefficient heat transfer which lead to incomplete evaporation. Incomplete evaporations are identified as main reason for the particle deposition at the dying wall. The identifying of this zone may help to design strategy to improve the flow in the drying chamber and decreased the loses of the powder due to the particle deposition. In future, the particle tracking will be conducted, and the heat profile will be discussed to develop the drying curve of the particle to help the strategy to improve heat distribution for particle deposition reduction. [ABSTRACT FROM AUTHOR]

Convective heat transfer coefficients for palm fatty acid distillate have been measured in a batch stirred tank. The heat transfer took place at a dynamic stage in jacketed tanks with a working volume of 3.5 and 10.0 liters, at temperature ranging from 60 to 80°C and Reynolds number ranging from 1000 to 6000. The results indicate that the convective heat transfer coefficient is in the range of 230 to 680 W·m-2·°C-1. The data fit well with the existing empirical model and can be expressed as Nu=0.5·Re⅔·Pr⅓ where Nu, Re, and Pr are Nusselt, Reynolds, and Prandtl numbers. [ABSTRACT FROM AUTHOR]