To further improve the energy conversion efficiency of internal combustion engine, the transient and complex air flow movement inside the cylinder needs to be better understood and controlled. Although the in-cylinder flow fields are highly stochastic with strong cycle-to-cycle fluctuations, machine learning can still provide an efficient way to learn and regress the complex flow movement process inside

The composite adsorbent of natural mesoporous powder of Wakkanai siliceous shale (WSS) impregnated with LiCl has been investigated. In this study, the slurry of WSS–LiCl with acryl resin as a binder was prepared for fabricating an adsorbent-filled heat exchanger (HEX). The optimal LiCl content for the impregnation with WSS was 20 wt%, which was chosen from the relation between water uptake and pore

In this study, a numerical simulation and experiments were performed to analyze the formation process of splat in the laser texture groove of filling molybdenum droplets during atmospheric plasma spraying. Texture grooves were extracted using a 3D surface topography instrument, and the heat transfer and phase transition processes of droplet hydrodynamics were analyzed. A 3D numerical model of the droplet-filling

Operating Li-Ion cells at adverse temperatures can lead to performance decrease and faster ageing effect. A thermal management system (TMS) designed to guarantee the cells isothermal condition is therefore necessary. Phase Change Materials (PCM) can form part of an efficient TMS based on passive cooling. However, when Li-Ion cells are exposed to extreme electrical regimes, PCMs cannot recover all of

With the development of building energy saving technology, low-temperature two-phase closed thermosyphon (TPCT) will be widely used in building energy supply and storage. However, the non-condensable gas (NCG) can affect the performance of TPCT. In this paper, experiment, theoretical heat transfer model and CFD simulation model have been established to comprehensive analyze the operation performance

Experimental investigations of mainstream turbulence intensity (Tu) effect on conjugate heat transfer performances, total pressure loss and solid thermal deformations of vane laminated cooling end-walls (LCEs) have been carried out under two engine-near mainstream-to-coolant temperature ratios of 1.4 and 2.0. Influences of parameters of internal elements of LCEs were discussed. A servicing film cooling

Range Extender has been proven to be an attractive option to prolong the driving range of Electric Vehicle (EV) and reduce baneful emissions in automobile industry. Compared with the conventional Diesel-Engine-based Range Extender (ICERE), the Micro-Gas-Turbine-based Range Extender (MGTRE) demonstrates less emissions and higher power-to-weight ratio, about 0.48-0.8 kW/kg. This paper formulates a systematic

This paper investigates the design and thermodynamic optimisation of both sub- and transcritical organic Rankine cycle (ORC) power systems featuring radial turbines via performance calculations using mean-line models. The emphasis is on rapid performance predictions for a given turbine geometry, as well as geometric optimisation for a given heat source. From three specified quantities, which are the

To investigate the influence of inlet temperature and velocity of mold cooling water on the heat transfer effects in a continuous casting mold, a three-dimensional fluid flow and heat transfer coupled model was established, containing steel, copper tube and cooling water zone. Using Fluent, this model simulated the flow and heat transfer of liquid steel and cooling water, solidified shell growth, and

Efficiency enhancement of thermal energy conversion and utilization is one of the critical issues in space exploitation and exploration. With the full consideration of material characteristics, space charge effect and Joule dissipation, thermionic conversion models were established based on Richardson's law. The models were coupled with a thermo-mechanical simulation code, developing the comprehensive

We propose a liquid cooling system incorporating a porous medium combined to the multiscale flow manifold. Specifically, this work compares two types of porous media by varying the porosity: the first type only includes a metal foam layer, and the second incorporates an additional circular pin-fin array within the metal foam. The thermohydraulic performances of each type such as the average junction

It is a challenging job to develop a finned tube that possesses highly efficient condensation as well as boiling heat transfer enhancement. A stepped lattice finned tube (SLFT) with two layers of staggered fins produced on the side wall of spiral grooves of tube surface is designed and fabricated to achieve the goal. The overall heat transfer performance, shell side and tube side heat transfer performance

Using the step displacer in two stage pulse tube refrigerator has already been proved as a sufficient way to improve the efficiency. In this article, an experimental setup has been manufactured. A no-load temperature of 16.9K is achieved with a step displacer type gas-coupled pulse tube refrigerator filled with stainless steel mesh. The influence of the connecting tube between pulse tube hot end and

This paper reports the behavior of water droplets on a topography-based, radial gradient on a metallic surface. The radial gradient was designed to concentrate water in the center region through the spontaneous motion and coalescence of individual droplets on the gradient pattern. In this work, parallel microchannels having a fixed width (∼25 μm) and depth (100 μm) but variable spacing were used to

This work presents a novel approach to improving the load flexibility of coal-fired power plant by integrating high temperature thermal energy storage (HTTES) through additional thermodynamic cycle. It aims to investigate the feasibility of introducing an HTTES-aided additional cycle into the steam-water cycle of conventional coal-fired power plant and to test how a high round-trip efficiency can be

Natural draft dry cooling tower is attractive in recent decades with its superiority of zero water loss. Some old thermal power plants are under high pressure of waste water reducing emission, thus the natural draft wet cooling tower is obsoleted. Reconstructing natural draft wet cooling tower into natural draft dry cooling tower is attractive for the saving of capital expenditure. But it has not been

The aim of this paper is the numerical study of two new configurations of the Barra-Costantini system using building integrated semi-transparent PV technology. Each configuration is integrated into a room located in Ksar Chalala in Algeria. In the first new system, the glass of the conventional Barra-Costantini system is replaced by a PV glass panel. While in the second one, a single glass is placed

Lithium-ion (Li-ion) batteries are the most promising power source for pure electric vehicles (EVs) and hybrid electric vehicles (HEVs) due to the batteries’ high specific energy, low self-discharge rate, low weight, long lifecycle, and no memory effect. The enormous heat generation, however, limits the performance and even causes safety problems. Thermal control of the battery cells remains a challenging

This paper proposes a self-driven wet-hot flue gas total heat recovery system according to the characteristics of the heat transfer process of flue gas condensation, which uses the sensible heat in the high-temperature section to drive the system and complete the deep waste heat recovery of flue gas. The effect of flue gas and secondary water flow rate, flue gas and secondary water inlet temperature

The rising of municipal solid waste generation is a serious current problem, whose incorrect disposal leads to major impacts to human health and the environment. Waste-to-Energy systems have been some of the adopted solutions but they carry the burden of the emission of pollutant gases. To control such emissions, international agreements have introduced the concept of the carbon tax, i.e. a levy on

Water adsorbent AQSOATM FAM-Z02 (Z02) coatings and pellets were evaluated in our custom-built lab-scale sorption chiller with two adsorber beds. Two finned-tube heat exchangers (HEX) (4.08 L) were coated with Z02 by Mitsubishi Plastics and compared with two other HEX that were packed with Z02 pellets. When tested with 15, 30, 30 and 90 °C operating temperatures for the evaporator, condenser, adsorption

A large amount of water and energy can be recovered in the flue gas after wet desulfurization. In order to explore the performance of the packed tower as a direct contact heat exchanger between flue gas and water, we measured the resistance and temperature field distribution of packed tower through on site pilot scale experiments, filled the gap in previous studies that lacked field trials and high

Suspended photocatalytic water splitting for hydrogen production is one of the most promising method for large-scale utilization of renewable energy in the future, and it is a complex reactive multiphase flow system involving radiation field. In this study, a computational fluid dynamics model of reactive multiphase flow for the photocatalytic tubular reactor with solar concentrator used for hydrogen

The wettability characteristic of wet channels plays an important role in cooling performance of an indirect evaporative cooler (IEC). To improve its wettability, porous ceramic is used as a novel material for IEC. The porous structure provides hydrophilic feature and water storage capacity. Therefore, the wet-bulb efficiency of the cooler can be improved because of higher wettability and larger specific

In this study, the performance of an open thermochemical energy storage (TCES) system integrated with a flat plate solar collector is evaluated using a simplified dynamic model for space heating applications, considering a charging phase during the summer daytime and a discharging phase during the winter night. For charging and discharging operations, the time-varying solar flux (DNI) and ambient conditions

The lithium-ion battery has been considered as a power source of electric vehicles (EVs). An efficient battery thermal management system is essential for lithium-ion batteries with high cooling performance and long lifetime. The objective of this study is to investigate the performance improvement of a novel direct two-phase refrigerant cooling over a conventional liquid cooling for traction batteries

The fluctuation of gas exchange is easy to induce the free piston linear engine (FPLE) to run unsteadily, because the gas exchange, piston motion and combustion of FPLE are intimately coupled with each other. This work presents a simulation to investigate the effect of combustion variation on the gas exchange stability of a FPLE. A full-cycle zero-dimensional dynamic model and a geometric model for

Components downstream of the pump in the cryogenic liquid rocket engine were simplified to a horizontal pipe upstream of an injector. Cryogenic chilldown was investigated experimentally in this pipe by constant flow rate of LO2. The chilldown processes were discussed and the boiling curves were drawn to identify the boiling transition points, Leidenfrost point (LFP) and critical heat flux point (CHF)

The heat transfer performance of a composite porous heat pipe (CPHP, 95 mm × 60 mm × 2.5 mm) using a grooved porous structure as capillary wick was studied. Sintered copper powder was used as the main structure of the capillary wick and sintered as grooves. A new type of powder filling method was used to make a capillary wick and can reduce the use of graphite molds. The effects of heating power, wick

To understand the running status of membrane walls in an opposite firing boiler, a scale-down model furnace was established, and the temperature, heat flux, strain and stress distributions are investigated under four heating loads. Results show that the average membrane wall temperature and heat flux present a continuous increase from 42 oC and 16 W/m2 to 96 oC and 50 W/m2, respectively, with the heating

The body-centered cubic lattice sandwich panels have superior mechanical performance, and current works only focus on their mechanical performance. The effective thermal conductivity and heat transfer characteristics have not been reported. The effective thermal conductivity and heat transfer characteristics for a series of body-centered cubic lattice sandwich panel were explored by theoretical analysis

This study presents a dynamic simulation-optimization of a solar-assisted desiccant cooling system integrated with a ground source heat exchanger (SDCS-GSHE). Solar and ground source energies are used for regenerating the desiccant wheel (DW) and a pre-cooling process, respectively. The system is considered as an alternative for extremely hot and humid regions. Determinant design parameters of the

Transient and non-uniform heat flux from solar concentrators can affect the performance of solar thermoelectric generators, which generate electricity from concentrated solar radiation. Therefore, this paper presents a detailed three-dimensional study on the effect of transient and non-uniform heat flux on the performance of a solar thermoelectric generator (STEG). COMSOL 5.4 Multiphysics software

High-efficiency photo-thermal conversion is an attractive approach for solar thermal energy to alleviate energy crisis. In this work, MWCNT-H2O nanofluids were prepared and its photo-thermal conversion properties were characterized. Moreover, an optical fiber as internal light source was introduced into direct absorption solar collector (DASC), in which the photo-thermal conversion performance of the

The present study compared measured heat transfer coefficients for supercritical pressure R134a in a horizontal internally ribbed tube (din=15.5 mm) and in a smooth tube (din=16 mm) for mass fluxes, G, from 100-350 kgm-2s-1, heat fluxes, q, from 10-25 kWm-2, pressures, P, from 4.26 to 5 MPa and inlet temperatures from 70-105°C. The heat transfer coefficients, buoyancy effects and pressure drop are

Laminar mixed convection characteristics in a wall driven porous cavity with an isothermally heated square blockage inside have been investigated numerically by the Non-orthogonal multiple-relaxation time lattice Boltzmann method (MRT-LBM). Various directions of wall driven and placement of the blockage have been considered. In the current study, the geometrical and flow parameters being investigated

At present, there is great interest in indirect evaporative coolers (IECs), which can be effectively used to increase energy efficiency of HVAC systems, with particular attention to data center applications. In such devices, performance significantly depends on the formation of an adequate water layer on heat exchanger plates. Therefore, efforts should be made to promote water spreading through an

Random Walk algorithm with Compulsive Evolution can simultaneously optimize the continuous (heat load) and integer (structure) variables in heat exchanger networks, by giving a random step length to heat load and setting the minimum heat load. Meanwhile, the structural mutation is allowed, as imperfect solutions may be accepted, in the low probability event that it may avoid entrapment in the local

Thermocline energy storage systems can be adapted to store energy in a tank where the hot fluid is pumped in during a charging cycle and cold fluid during a discharging cycle, substituting the need for two storage tanks. Here, a numerical investigation of a hot air flow transferring thermal energy to a solid porous bed is performed to evaluate the influence of the thermal conductivity and capacity

Metallic plasmonic nanofluids have been adopted to enhance the photothermal conversion in direct absorption solar thermal collectors, however, their absorption band is not broad enough to realize a sufficient adsorption. Driven by the Local Surface Plasmon Resonance (LSPR) effect, this work explores the enhancement of triangular nanosheets in photothermal conversion, to facilitate the optimization

The study of reproducing high altitude icing environment based on the icing cloud simulation system has gradually become a concern for researchers. They found that the parameters of water droplets were one of the most critical factors affecting the state of icing. However, the influence of nozzle arrangement on droplet parameters in the icing cloud simulation system is usually neglected. By reprogramming

A linear non-equilibrium thermal and deformation transport model for hematite pellet in dielectric and magnetic heating was developed to demonstrate the drying behavior and mechanical performance. The moisture ratio profiles, temperature distribution and deformation fitted the experimental values well with reasonable deviations. The collapses and cracks were apt to appear along the circumferential

This paper concerns the modeling of vertical coaxial heat exchangers for Ground Source Heat Pump (GSHP) applications. Vertical coaxial borehole heat exchangers (CBHEs) can be buried at depths which are even higher than the conventional ones. In this case they are referred as Deep Borehole Heat Exchangers (DBHEs). As it is known, there is indeed a strong recent tendency, especially in the Scandinavian

In this study, the heat transfer characteristics of supercritical water in a horizontal double-pipe were investigated via experiments and numerical simulations. The influence of pressure (23 MPa, 25 MPa and 28 MPa) and mass flow rates (540 kg·h-1, 573 kg·h-1 and 604 kg·h-1) were studied by experiments at the inlet temperature of tube 563 K, the inlet temperature of shell varying from 626 K to 756 K

A practical case of a single-phase natural circulation (SPNC) loop having a considerable circulation length and non-uniform structures is investigated via experimental and analytical approaches. The target facility (Facility to Investigate Natural Circulation in SMART, FINCLS) corresponds to the type of vertical heater and vertical cooler (VHVC), and the maximum height and total circulation length

The falling film flow has gained wide attention in recent years, due to its extraordinary performance in different heat exchangers in terms of high heat transfer coefficient and low energy consumption. In this paper, a series of experiments are conducted in a smooth tube and a finned tube respectively, in order to investigate the heat transfer characteristics of the cooling falling film flow outside

An air dehumidification system with internally-cooled plate membrane-based liquid desiccant dehumidifier is presented. The novel system can effectively dehumidify the ambient air by the internally-cooled dehumidifier. On the other hand, the dehumidifier and regenerator are in independent operation due to the separate solution passage, which makes the system more flexible and energy saving. In this

This paper proposes numerical unsteady heat transfer model that predicts the transient heat transfer in the double U-tube borehole heat exchanger (BHE) where the U-tubes can operate with either different or equal mass flow rate and inlet fluid temperature. The implicit numerical method applied on heat transfer equations, obtained from energy balance on fluid and grout and ground nodes, was utilized

Aiming at deepening the grid penetration of solar energy and reducing the carbon emission, a novel solar-gas combined cycle (SGCC) system using the solar direct steam generation (SDSG) technology is proposed in this study. The design principle and configuration of the proposed SGCC system is provided. The EBSILON code is used to establish the calculation model of the SGCC system. The performance comparison

Loop heat pipes are passive heat transfer devices which can meet the heat dissipation requirement of high-power electronic devices in aerospace and terrestrial applications. This paper investigates the operating characteristic of a stainless steel-ammonia loop heat pipe with a flat disk evaporator. A biporous wick made from sintered nickel powders was used to produce the capillary force. The heat transfer

In aim to improve system efficiency and flexibility at deep peak-load operation, a novel supply-side load regulation strategy was proposed for gas turbine-based CCHP (combined cooling, heating and power) systems, where the load was regulated through compressor bypass air extraction (CBAE) for energy storage in addition to inlet guide vane (IGV) regulation strategy. The part-load performance of gas

This study introduces the field measurement on a single air inlet induced draft cooling tower (SIDCT) under crosswind conditions. A three-dimensional numerical model is developed and validated to collaborate with the field measurement. The primary objective of this study is to evaluate the effect of environmental crosswind (both direction and velocity) on the thermal characteristics of SIDCT, such

This paper addresses the analysis of different configurations of carbonator for thermochemical energy storage for concentrated solar applications. The design of this equipment is different from the previous experience of calcium looping cycle for carbon capture. The use of fluidized beds and large particles are not feasible for this novel application of calcium looping. New reactors and different arrangements

The operation of R290 air conditioners at cold ambient temperatures can lead to sub-atmospheric suction pressures, risking the safety and reliability of such air conditioners. In this study, the effects of several system control strategies on the startup characteristics were investigated, with the goal of avoiding vacuums in air conditioners. The variations in the degrees of superheating and the changes

Effective thermal management for light-emitting diodes (LEDs) is critical, as temperature significantly affects their lifetime and performance. In this study, a system combining a thermoelectric cooler (TEC) and a microchannel heat sink (MHS) is investigated experimentally for thermal management of high-power LEDs. Nanofluids and water are used as coolant. The LED substrate temperature (Ts) is measured