Over the past decade, different variants of desiccant cooling system integrated with direct/indirect evaporative cooler(s) have been simulated and/or analyzed in specific climatic conditions under rather limited operating parameters and for limited durations of time. Complete seasonal and multi-climate performance analyses of solar desiccant cooling system integrated with efficient, indirect Maisotsenko

Over the past few decades, experimental studies have been conducted on the condensation heat transfer of vapor mixtures. However, the local heat transfer characteristics of vapor mixture affected by surface tension have not been fully investigated. The present work, for the first time, suggested the CFD simulation method for the Marangoni condensation of ethanol-vapor mixture and analyzed the calculated

Droplet formation in a flow-focusing device was modeled using the open source CFD package, OpenFOAM, with the VOF model for two-phase flow. Predictions using the interFoam solver and a power-law non-Newtonian model were first validated against experimental data in the literature. Then, the formation of Newtonian fluid droplets in power-law fluids was modeled during tubing, squeezing, dripping and jetting

Unsteady boiling bubble behavior of water in a square pipe under a low pressure and subjected to natural convection was experimentally studied. The measurements included temperature and pressure, and the bubble behavior was visualized using a high-speed camera. The boiling phenomena in the pipe showed the three stages characterized by cavitation, intermediate, and fully developed boiling bubble in

Numerical simulation of the influence of operating conditions of the furnace on its performance characteristics like heat flux distribution, Furnace Exit Gas Temperature (FEGT) and NOx emission levels was performed for a tangentially fired pulverised coal boiler. The results revealed that the FEGT and NOx emission are slightly higher when the top seven coal nozzles are in operation compared to the

For exploring the complex heat and mass transfer in the micro-particle fixed bed, the device to measure thermal conductivity was designed and built. The experiments showed that the error was less than 2.97% after calibrated, and reproducibility was good. Effects of particles diameters, porosity, flow rate and ion exchange on the thermal conductivity of micro-particle porous materials were investigated

In this experimental study, the influence of combined passive technique on heat transfer, friction factor, and thermal performance factor are investigated in a double pipe heat exchanger fitted with different turbulators and GO-Water nanofluid. Experiments were conducted for a fixed flow rate of (Re = 2500) in the inner tube (hot fluid); for varying flow rates (500 ≤ Re ≤ 5000) and volume concentrations

Fouling still remains one of the most difficult problems for the use of heat exchangers. A methodological process of advanced analysis of experimental data on heat exchangers fouling allowing building predictive models is necessary to determine the fouling degree. Here, three different methods were used to predict the fouling resistance from some easily measurable variables of the system which are:

Improving building energy efficiency is one of the most important challenges towards the mitigation of climate change concerns. Buildings use significant amount of energy for cooling loads. Development of new night-time and day-time radiative cooling modalities by roofs is essential for reducing the energy consumption during the summer months. If a surface is desired to be kept cool while exposed to

The application of fully pulsatile flow in liquid-liquid two-phase extraction contributes to augment the interfacial mass transfer. Further, the inclusion of air at the top of the central test section combined with pulsatile flow augments the extraction or the mass transfer process. Toluene-water is chosen as an organic-aqueous two-phase liquid-liquid system with acetic acid as the transfer species

A unique boiling heat transfer study of wetting fluids in a vertical three-dimensional rectangle microchannel was carried out in this paper, to develop a novel passive three-dimensional chip stack cooling technology. The base liquids were deionized water and R113, and Sodium dodecagon sulfate (SDS) was used as a surfactant, which is added into the base fluids for developing wetting fluids. The length

The results obtained from a drying experiment using infrared heating are compared to those obtained from an analytical model based on correlations for the mass transfer coefficients, which are commonly used to obtain evaporation rates for drying applications. It was shown that the mass transfer coefficients calculated by natural convection correlations are approximately ten times lower than those measured

Fouling of heat exchangers in energy and power plant industry, oil and gas industry, pharmaceutical and food process industry, industrial waste heat recovery is a major problem which needs to be solved urgently. In the United Arab Emirates, a majority of oil & gas processing plants are located in the desert where water accessibility is limited, thus fin-fan type of heat exchangers are used for cooling

Thin film gauges (TFGs) are most commonly used for heat transfer measurement, especially in short duration test facilities. Performance improvement of these sensors through alteration in their geometric construction or through additives like nanomaterials in the sensing material has been attempted. Present studies propose a robust methodology for sensor making which accounts the effect of surface roughness

To reveal the mechanism of nanofluids in heat transfer and mass transfer, experimental investigations on the rheological properties of TiO2/water nanofluids with four solid volume fractions (0.012%, 0.238%, 1.227%, and 2.556%) and 0.152%, 0.182%, 0.213% and 0.246% MWCNT-TiO2/water hybrid nanofluids are carried out. The measurements covered in this paper are hysteresis loop; 3ITT test; temperature sweep

In the current study, a new single-step forced electrodeposition method is proposed for the fabrication of intended micro/nanostructured surfaces. In this method, high thermal conductive Cu-TiO2 nanoparticles (10 nm to 20 nm) are deposited on copper sample with higher current density followed by sintering at reducing atmosphere. Initially, the nanoparticles are deposited uniformly on the copper sample

The kinetic gas theory, in particular the equations of Chapman and Enskog, proved to be good and widely applicable approximations for modeling transport properties like diffusion coefficients, viscosities and thermal conductivities. However, these equations rely on at least the Lennard-Jones parameters and for polar gases also the dipole moment. In the scientific literature, the Lennard-Jones parameters

Drying characteristics, color, pH, °Brix, energy, thermal image and micrograph parameters of the whole, half cut and puree black chokeberry samples were analyzed. Experiments were carried out with a freeze dryer at a temperature of −50 °C. The results indicated that drying time was being highest with whole samples, whereas the lowest with puree samples. According to the nine different thin-layer drying

Accurate experimental characterization of longitudinal vortices induced by rectangular winglets is necessary to develop and validate numerical models that can predict these flows. For this aim, an experimental investigation is conducted to examine the characteristics of longitudinal vortices generated downstream rectangular winglets in fully developed turbulent channel flow. A row of rectangular winglet

In June 2019, this journal published “Assessment of the effects of temperature and moisture content on the hygrothermal transport and storage properties of porous building materials” Ferroukhi et al. (Heat Mass Transf 55:1607–1617, 2019). A thorough check reveals that this target paper is riddled with errors. This comment aims at pointing out the flaws, and, given their multitude and magnitude, finally

This paper describes the effect of inorganic adsorbents on the hygrothermal performance of insulating materials. The addition of the inorganic adsorbents leads to significant effect to the microstructure and mechanical properties of these materials. The thermal conductivity rang of the materials containing adsorbents from 0.095 to 0.116 (W/m−1 K−1) is lower than that of those without adsorbents (0

Energetic and exergetic analyses of the plate heat exchanger are experimentally performed using Al2O3–TiO2 hybrid nanofluid as a coolant for sub-ambient temperature application to study the effect of nanoparticle volume ratio at various nanofluid flow rates ranging 2.0–4.0 lpm and inlet temperatures ranging 10–25 °C. The Al2O3–TiO2 hybrid nanofluids of 0.1% total volume concentration with different

In this paper, a visualization experiment was conducted for multiphase flow in the evaporating hot water tower. The high-speed camera was used to record the motion of a single bubble above the 3 mm single-hole sieve tray in the hot water tower. The pictures were processed by image processing software to obtain the characteristics of the bubble. In the experiment, non-condensable gas was added to the

Modified cassava flour is produced by drying processes and usually, in Indonesia, stored for several months after production up to selling and utilization. During storage, flour can experience degradations in quality, particularly if ambient conditions are unfavorable. In the present study, the adsorption and desorption isotherms of modified cassava flour were determined over a range of water activities

The purpose of this work is to experimentally establish the combined influence on the flow and thermal resistance of an exhaust pipe wall formed by a porous, compliant layer with overlying discrete roughness elements exposed to the pulsating exhaust gas flow of a combustion engine. Through measuring the streamwise pressure drop over and radial temperature differences in different pipe samples for a

Spray impingement cooling is the major method currently used to cool steel after the hot-rolling process. In this study, dual nozzles are used to investigate the cooling character of the flat plate using for the spray impingement cooling process. Based on an experimental temperature measurement, a three-dimensional numerical model is set up to calculate the transient heat transfer coefficient of the

The experimental work aims at investigating the influence of surface roughness on heat transfer by using different nozzles. Part of the rough surfaces are provided directly by the industry. These surfaces of casting products possess considerable roughness up to millimeters which can be either unstructured or with typical grooves in the casting direction. The understanding of its effect on cooling hot

Date seed oil is a good source of natural antioxidants due to the presence of phenols, tocopherols, and sterols. The present research is the first study on the extraction of date seed oil by combining the ultrasound-assisted aqueous enzymatic extraction method and the cooking pretreatment. In this study, the effects of two independent variables namely the sample to solvent ratio (at six levels of 1:

Removing moisture in the wet farm products through the open air ventilation is a traditional postharvest treatment method. However, its overall energy consumption is high and the drying time is long. Here, a combined system is proposed through integrating a bottom organic Rankine cycle (ORC) to a top closed farm products air drying cycle to save energy and decreasing the drying time. Based on a steady

In this study, the heat transfer enhancement due to using Silicon Carbide nanofluid flowing through the tube side in a shell and tube heat exchanger is studied. Nano-fluid concentrations are 0.25, 0.5, 0.75 and 1 Vol.%, respectively. The hot water is passed through the shell side at temperatures of 35, 45 and 55 °C. The flow rate of nanofluid is adjusted at 100, 150, 200, 250 and 300 (L/h), while,

Industrial heat exchanger fouling is generally defined as the accumulation and formation of undesired materials on the exchange surface. Experimental measurements of degree of fouling are both difficult and time consuming and often do not provide accurate results. However, the modeling of the thermal resistance of fouling can inform us on the evolution of this phenomenon. The present work aimed at

The present article experimentally examines the application of ZnO nanoparticles in refrigeration cycle. Nanoparticles overcome the energy consumption issue by improving the compressor lubrication characteristics. In this study, the ZnO nanolubricant is proposed as a promising lubricant to improve the lubrication characteristics of domestic refrigerator compressors. Effect on compressor suction-discharge

An external rotor permanent magnet synchronous generator (ERPMSG) model for Range-Extended Electric Vehicles is developed. The temperature field simulation model of the ERPMSG is established. Experimental test of the winding temperature shows that the simulation model is believable and then it is used to optimize the structural parameters of the cooling water channel. It is found that the pressure

The paper describes a computational study and an experimental investigation of aqueous potassium carbonate droplets in superheated steam flow for potential applications in mitigation of superheated geothermal steam. The computational model included the boiling point elevation due to the droplet salt concentration as well as other concentration-dependent physical properties of the salt solution. Various

The aim of this work was to investigate the thermal behavior of solid wood used as building materials. Three tropical wood species namely Iroko (Milicia excelsa), Bilinga (Nauclea diderrichii), and Tali (Erythrophleum suaveolens) were chosen. The thermophysical properties in the longitudinal, radial and tangential directions were determined experimentally for different moisture contents. Asymmetrical

The present work aims to investigate the heat transfer characteristics of heated cylindrical pins within an air-filled rectangular enclosure experimentally in a natural convection dominated regime. The experiments are performed to analyze the effects of fin spacing (25 mm ≤ S ≤ 100 mm) and Rayleigh number (248,659 ≤ Ra ≤ 578,395) as key factors at constant pin height (l = 25 mm) and pin diameter (d = 10 mm)

Seven different Aluminum fins under natural convection conditions were investigated experimentally and numerical. The first fin has a flat shape; while the second fin has a new proposed wavy shape. The rest have the same wavy shape but with different perforations distribution. Fifty 1 cm circular perforation were made on each of the five fins. Vertical cylindrical heat sink with 1000 W heater inside

In this paper, an experimental study was carried out in order to investigate the effects of Al2O3/water nanofluid with a mean diameter of 50 nm on heat transfer performance in a counter flow double-pipe heat exchanger. The nanofluid was used as cold side fluid and passed through the inner pipe of the double-pipe heat exchanger considering fully developed turbulent flow regime with different Reynolds

The wasted energy from a car exhaust can be considered as the heat supply for an absorption refrigeration cycle. In practice however, application of such cooling systems in automobiles has been facing a number of technical restrictions one of which is once the car engine runs idle or at low speed. To tackle this matter, the present experimental study has been carried out. A commercial diffusion absorption

The present paper presents the results of an experimental investigation on nucleate pool boiling heat transfer of pure fluid R-134a and environmentally harmless azeotropic refrigerant mixtures R32/R125 (R-410A) on a plain horizontal copper tube. The experiment has been carried out at saturation temperatures of 5, 10, 15 and 20 °C for heat fluxes ranging from 10 to 70 kW/m2 with an interval of 10 kW/m2

The development of sustainable trucks has drawn a lot of attention lately. However, the reduction of fuel consumption and emissions related to deep frozen food transports has not yet been satisfactorily considered. In this paper, a thermal Large Eddy Lattice Boltzmann Method (LES-LBM) is applied to investigate two concepts for optimized refrigerated vehicles: (a) the inclusion of vacuum insulation

Access to drinking water in many parts of the globe is shrinking over the years and much of the water resources are polluted or unpurified. North Africa is facing a huge water shortage due to drought and climate change. Water desalination has become very popular and serves as solar distillation which is proving to be an economical, simple and ecological technique, especially in rural and remote areas

This study investigated the numerical analysis of Nusselt number and entropy generation of copper/water nano-fluid under turbulent flow conditions at volume fraction ranges of 1–5% within a helical coil under constant heat flux. The nano-fluid behavior was modeled through a single-phase model. Flow and heat transfer governing equations were discretized using finite volume method, and the SIMPLE algorithm

The objective of this study is to demonstrate that strongly impinging jets-in-crossflow (JIC) will result in a counter flowing jet that will probably be unsteady. This numerical study was conducted in a 360o (complete cylindrical duct) computational domain using a steady-state Reynolds-Averaged Navier Stokes, RANS, and time-dependent URANS at various momentum-flux ratios J. Asymmetry in a steady-state

PCMs (phase change materials) applied in heat storage technology are on the one hand characterised by relatively large specific heat capacity, and on the other hand by relatively low thermal conductivity (e.g. 0.2 W·m−1·K−1) for paraffin), which prolongs the charging/discharging cycles of heat accumulators based on such materials. In order to improve the heat transfer within PCMs, spatially shaped

Abstract The prediction accuracies of the two-phase heat transfer coefficient for the flow in a small channel, which are usually based on the mean absolute error (MAE) between the correlation and experimental data, have remained unsatisfactory. Conventionally, the regression method has been used to determine the correlation that best represents the experimental data. In this paper, an improved heat

Abstract The transient temperature measurements and subsequent prediction of heat flux are prime requirements to quantify instantaneous heat transfer characteristics in short duration unsteady flow phenomena. Coaxial surface junction thermocouples (CSJT) are efficient laboratory tools that can cater both the requirements of measuring continuous as well as instantaneous temperatures. In addition, they

Abstract In this study, the production of green olive, chickpea and haricot bean added potato chips was investigated in order to produce a functional snack food appealing to consumers from all age groups. Chips were produced by hot air drying (75–85 °C), vacuum drying (75–85 °C, 250 mbar), and microwave drying (90 W and 180 W). The effective diffusion coefficient of chips was calculated as between

An experimental study on the dynamic thermal environment and the occupant’s overall thermal sensation of the vehicle cabin in automatic air conditioning mode under different driving states respectively in summer and winter is conducted. Experimental results show: The temperature and humidity‘s change with time of the passenger compartment will be affected by the driving state under the same set temperature

Abstract The impingement behavior is inevitable during the injection process of urea water solution in selective catalytic reduction aftertreatment system of diesel engine. The impingement contributes to the formation of liquid film on the pipe wall and mixer, and it will block the pipe and reduce the urea water solution decomposition efficiency. In this work, the morphological changes of the spray

Abstract Several numerical and experimental studies of natural convective heat transfer from two-sided heated horizontal plates are available. In the numerical studies it has usually been assumed that the plate is thin, effectively having no thickness, whereas plates of finite thickness have been used in the experimental studies. The main aim of the present study is to determine whether the plate thickness

The article Experimental assessment of Al2O3 and Cu nanofluids on the performance and heat leak of double pipe heat exchanger, written by Esam I. Jassim & Faizan Ahmed, was originally published electronically on the publisher’s internet portal (currently SpringerLink) on 16 January 2020 with open access.

Velocity and concentration profiles in a pipe flow was measured downstream of injection of a tracer gas at the pipe centerline. The pipe had diameter D = 0.2 m and two Reynolds numbers, Re = 50000 and Re = 100000, were used. The profiles were measured at positions 5D and 10D downstream of the injection point. Three different industrial relevant geometrical configurations were used upstream of the injection

Sodium chloride salt is used in the cheese salting because it promotes sensorial changes besides preserving the food, but in excess can cause hypertension. Therefore, it has been partially replaced by potassium chloride to not affect the sensory characteristics. In this work the mozzarella cheese was subjected to the diffusion of Na+ and K+ in brine by static and stirred immersion. The diffusion was

Based on the thermal integrity testing method of foundation pile, distributed optical fiber temperature sensing (DTS) technology was applied to testing the integrity of a cast-in-place pile. A theoretical model was established for the heat transfer and temperature characteristics in consideration of the physical properties of piles and the surrounding media. By establishing a model of a pile with and

Abstract Heat exchanger fouling is a complex process and closely associated with the operating conditions and surface properties. Many studies have been carried out to model various stages of the fouling process. These include the induction period, initial fouling rate (IFR), and fouling growth. Among them, IFR is of primary importance since its reduction leads to a longer operating time. Several studies

With the increase in laser technology for ophthalmic surgeries, the knowledge of the heat transfer mechanism in the human eye becomes increasingly important. The accuracy in predicting thermal behavior is linked to the use of adequate thermal and numerical methods. In this way, this study presents the results of two two-dimensional models, cartesian and axisymmetric in cylindrical coordinate, to calculate

The current numerical study has explored the effect of incorporation of rectangular winglets with circular, flat and oval tubes on the performance of compact heat exchangers. Rectangular winglet pairs are mounted behind the tubes at a span angle of 5° to obtain the enhanced performance. The obtained results show that fin and oval tube heat exchanger (FOTHE) having rectangular winglet pairs (RWPs) provides

One of the common problems of water-cooled panels which is carrying off-gas from Electric Arc Furnace is cracking and punching in their steel bodies due to the high thermal stresses which cause water leakage into the furnace and delaying the production. In this study, heat transfer in the elbow of water-cooled panels was simulated in the steady and transient states using computational fluid dynamics

Abstract Boiling utilizes latent heat of vaporization of the fluid to dissipate large amount of heat at small temperature budgets. Surfaces with micro−/nano-scale wettability patterns have been shown to improve the heat transfer coefficient during pool boiling. In this work, we propose a simple and cost-effective technique to fabricate heterogenous surfaces with macroscale wettability patterns comparable