Showing papers in "Applied Thermal Engineering in 2012"

TL;DR: In this paper, a literature review focuses on the applications of Computational Fluid Dynamics (CFD) in the field of heat exchangers, and the quality of the solutions obtained from these simulations are largely within the acceptable range proving that CFD is an effective tool for predicting the behavior and performance of a wide variety of heat- exchangers.

TL;DR: In this paper, the melting phase change heat transfer in paraffin-saturated in open-celled metallic foams was experimentally and numerically studied, and the effects of foam morphology parameters, including porosity and pore density, on the wall temperature and the temperature uniformity inside the foam were investigated.

TL;DR: In this paper, the efficiency and energy behavior of Ground Source Heat Pumps (GSHPs) used for heating and cooling of buildings were investigated. But the main results pointed out the heat fluxes transferred to and from the ground and the efficiency of the system.

TL;DR: In this article, the laminar convective heat transfer of an alumina-water nanofluid flow inside a wide rectangular microchannel heat sink (94.3mm, 28.1mm and 580μm; length, width and height, respectively) both numerically and experimentally was studied.

TL;DR: In this article, a numerical investigation on forced convection with nanofluids, composed by water and Al 2 O 3 nanoparticles, in a two-dimensional channel is carried out.

TL;DR: In this paper, the authors analyzed the thermal-hydraulic behavior of three types of enhancement technique based on artificial roughness: corrugated tubes, dimpled tubes and wire coils.

TL;DR: In this article, the effects of spray impingement, injection parameters, and exhaust gas recirculation (EGR) on the combustion characteristics and exhaust emissions of a premixed charge compression ignition (PCCI) diesel engine were investigated using a single-cylinder test engine and an optically accessible engine.

TL;DR: In this article, the study of different bottoming Rankine cycles with water-steam and/or ORC configurations in classical and innovative setups such as a waste heat recovery system in a Heavy Duty Diesel (HDD) Engine is presented.

TL;DR: In this article, waste heat from a process industry plant (100MW output) was used as the heat source for drying pine chips at 60wt% moisture, which could then be provided as the input fuel for a subsequent 40MW power plant.

TL;DR: In this paper, the performance of a pair of new vortex generators, curved trapezoidal winglet (CTW) has been experimentally investigated and compared with traditional vortex generators using dimensionless factors, which indicated the advantages of using this kind of vortex generators for heat transfer enhancement.

TL;DR: In this article, a heat spreader with phase change material (PCM) is described and its basic thermal characteristics are evaluated, which is a kind of pin-fin radiator, but instead if pins the thin wall pipes of small diameter form a heat transfer surface.

TL;DR: In this paper, an ANN model based on standard back propagation algorithm was developed to predict the brake specific fuel consumption, effective power and average effective pressure and exhaust gas temperature of the methanol engine.

TL;DR: In this paper, the performance of R1234yf and R134a was examined in a heat pump bench tester under the conditions for mobile air-conditioners (MACs).

TL;DR: In this paper, three nanoparticles of silica, alumina, and titania were used for the cooling of computer microchips, each with three different volumetric concentrations in the base fluid.

TL;DR: In this article, a one-dimensional transient heat transfer model has been developed and solved numerically using a finite difference technique to study the influence of phase change materials (PCMs) in external building walls.

TL;DR: In this article, a semi-hermetic reciprocating compressor was developed for application in CO2 refrigeration, and a test system was incorporated into the compressor performance test rig, with a focus on investigating the dynamics of the discharge valves.

TL;DR: In this paper, a composite material from synthetic or natural diamond in a copper matrix, having a thermal conductivity (TC) of 500 −900 W −m−1 K−1, is obtained by capillary infiltration.

TL;DR: In this article, the authors summarise the recent developments of lightweight, high performance heat pipes, and present methods or approaches to achieve the requirements of lightweight and high performance are introduced; however, there are still some limitations to the applications of lightweight materials such as magnesium due to its incompatibility with some working fluids.

TL;DR: In this article, the performance of a micro-channel with copper nanowires (CuNWs) coatings has been investigated experimentally, and the results from a single microchannel with bare surface are used as the baseline data.

TL;DR: In this article, the effect of syngas on the performance, combustion and emission characteristics of a diesel engine was studied at different loads, and three different volumetric compositions were examined in the diesel engine under dual fuel modes.

TL;DR: In this paper, the influence of the ORC parameters on the heat exchanger design and the heat exchange coefficients is investigated in the case of supercritical fluid parameters and the convective coefficients as well as resulting heat transfer surface is calculated for various fluid parameters.

TL;DR: A phase change composite (PCC) using a porous metal with a thermal conductivity that is two orders larger than that of the original phase change material (PCM) was developed in this paper.

TL;DR: In this article, an ORC system fitted on the exhaust and the coolant of a hybrid vehicle with a 1.8-L naturally aspirated gasoline engine was investigated. And the average improvements all over the map were 3.4%, 1.7%, and 5.1% respectively.

TL;DR: In this article, the relationship between working fluid properties and ORC common economic and thermodynamic performance criteria from a theoretical and an analytical point of view is explored, and the mapping of individual properties and performance criteria presented in this paper will provide a basis for the development of efficient and systematic strategies and approaches for ORC working fluid selection.

TL;DR: In this article, the authors proposed and simulated the performance of a hybrid two-phase cooling cycle with micro-evaporator elements (multi-microchannel evaporators) for direct cooling of the chips and auxiliary electronics on blade server boards.

TL;DR: In this paper, LiBr-H2O pair was used for the first time for absorption section of compression-absorption cascade refrigeration cycles, and the results showed that the thermal energy consumption of the LiBr and H2O pairs could be reduced by 35% and also general coefficient of performance (COPcyclegen) could be improved by 33%.

TL;DR: In this article, the authors proposed a new temperature measuring system for rotating cutting tools, which is composed of a thermocouple integrated into the drill or into the mill and positioned as close as possible to the cutting face and near the cutting edge.

TL;DR: In this paper, a continuous flow test chamber is used to evaluate the effect of the injector body temperature on the evaporation and combustion of the diesel spray diagnostic, and the relationship between injector and fuel temperature has been observed experimentally.

TL;DR: In this paper, an experimental setup is described and experimental procedures are detailed, and an evaluation of defrosting heat supplies and energy consumptions during a revere cycle defrost operation for the experimental ASHP unit is presented.

TL;DR: In this article, the effect of adding small amounts of hydrogen to gasoline-air mixtures on the performance and exhaust emission characteristics of a spark ignition engine was investigated, including thermal efficiency, specific fuel consumption, cyclic variations of the IMEP, and emissions of CO, NO and unburned hydrocarbons.