Preparation of composite aluminum automobile radiator by inversion casting

The inversion casting technics of producing three ply Al Mn/Al Si composite strap used in automobile radiator was studied. The physical processes of inversion casting, including the flux supporting reacting and volatilizing at high temperature, the melting and solidification when the elements of solid and liquid fresh alloys meet with each other, the mutual diffusion of elements in solid and liquid, the crystallization and forming of metallurgical combination and the following rolling process, were analyzed. At the same time, the composite mechanism of this technique was also discussed. [

Optimal Design of Multi-channel Water Cooled Radiator for Motor Controller of New Energy Vehicle

In order to improve the heat dissipation capability of motor controller for new energy vehicles,the water cooled radiator with multiple channels is optimized in this paper.The heat conduction between the heat source IGBT and the radiator,the convective heat transfer between the radiator and the coolant,the mechanical strength and the manufacturing cost are comprehensively considered during the optimization process.The power loss and thermal resistance of the IGBT unit are calculated at first,and finite element model of the radiator is established.On this basis,multi-physics coupling analysis of the water cooled radiator is carried out.Secondly,the sensitivity analysis is applied to verify the influence of structural parameters on the heat dissipation performance of the radiator system.The influence of coolant inlet velocity v,number of cooling ribs n,height of radiator ribs H on the maximum temperature rise T,the temperature difference ΔT between phase U and W,and the coolant pressure lossΔP are analyzed in depth,and the optimal range of the structural parameters for heat dissipation is obtained.Finally,an experimental platform was set up to verify the performance of the proposed structure of water cooled radiator for motor controller of new energy vehicle.The results show that the heat dissipation capability of the proposed radiator is improved compared with the initial design.

DEVELOPMENT OF SINGLE-PHASED WATER-COOLING RADIATOR FOR COMPUTER CHIP

In order to cool computer chip efficiently with the least noise, a single phase water-cooling radiator for computer chip driven by piezoelectric pump with two parallel-connection chambers is developed. The structure and work principle of this radiator is described. Material, processing method and design principles of whole radiator are also explained. Finite element analysis （FEA） software, ANSYS, is used to simulate the heat distribution in the radiator. Testing equipments for water-cooling radiator are also listed. By experimental tests, influences of flowrate inside the cooling system and fan on chip cooling are explicated. This water-cooling radiator is proved more efficient than current air-cooling radiator with comparison experiments. During cooling the heater which simulates the working of computer chip with different power, the water-cooling radiator needs shorter time to reach lower steady temperatures than current air-cooling radiator.

Influence of the Coolant Flow Containing Silver Nanoparticles (Ag) from an Aqueous Solution Based on Ethylene Glycol (EG50%) on the Thermal-Hydraulic Performance of an Automotive Radiator

A theoretical analysis of the influence of the flow of a coolant containing silver nanoparticle (Ag) in an automotive radiator is presented. The coolant fluid is composed of water or an aqueous solution of Ethylene-Glycol (EG50%) and silver nanoparticles. Ethylene glycol (EG) has been used in automobile radiators for many years due to its compatibility with metals and its anti-cooling properties. Silver nanoparticles are being incorporated into the development of high-precision surgical equipment. It is shown that the rate of heat transfer increases significantly using silver nanoparticles and ethylene glycol and water. There is a maximum for heat exchange between fluids in all analyzed coolant flows—the maximum moves to higher airflow rates when the coolant flow rate is increased. However, the energy dissipation in the stream also increases, but the relationship between the energy dissipated in the flow and the energy transferred in the form of heat is low, which justifies the use of silver nanoparticles and ethylene glycol, or silver nanoparticles and water as a coolant in the automotive vehicle radiator.

Numerical Study on Application of CuO-Water Nanofluid in Automotive Diesel Engine Radiator

Application of CuO-water nanofluid with size of the nanoparticles of 20 nm and volume concentrations up 2% is numerically investigated in a radiator of Chevrolet Suburban diesel engine under turbulent flow conditions. The heat transfer relations between airflow and nanofluid coolant have been obtained to evaluate local convective and overall heat transfer coefficients and also pumping power for nanofluid flowing in the radiator with a given heat exchange capacity. In the present study, the effects of the automotive speed and Reynolds number of the nanofluid in the different volume concentrations on the radiator performance are also investigated. The results show that for CuO-water nanofluid at 2% volume concentration circulating through the flat tubes with Renf = 6000 while the automotive speed is 70 km/hr, the overall heat transfer coefficient and pumping power are approximately 10% and 23.8% more than that of base fluid for given conditions, respectively.

CFD Analysis and Optimization of Automobile Radiator based on STAR-CCM+

This research talks about the radiator cooling system of the automobile engine,the radiator’ s fluidstructure interaction dynamics based on computational fluid dynamics( CFD) STAR-CCM+ software. The linear regression model of coolant determined by MATLAB software was imported into the user-defined field function of the software,using the standard K-Epsilon turbulence model to analyze temperature,pressure and velocity changes of the coolant in the radiator channel. In order to improve the efficiency of the radiator,it is necessary to analyze the structure of two kinds of heat sinks,and get better heat transfer effect.

Radiator Heat Dissipation Performance

This paper presents a set of parametric studies of heat dissipation performed on automotive radiators. The work’s first step consists of designing five radiators with different fin pitch wave distance (P = 2.5, 2.4, 2.3, 2.2, 2.1 mm). Then, we proceed to the fabrication of our five samples. The purpose of this work is to determine through our experiment’s results which one have the best cooling performance. This numerical tool has been previously verified and validated using a wide experimental data bank. The analysis focuses on the cooling performance for automobile radiator by changing several dimensions of the radiator fin phase as well as the importance of coolant flow lay-out on the radiator global performance. This experience has been performed at Hubei Radiatech Auto Cooling System Co., Ltd. For the cooling performance experience, we use JB2293-1978 Wind Tunnel Test Method for Automobile and Tractor Radiators. The test bench system is a continuous air suction type wind tunnel;collection and control of operating condition parameters can be done automatically by the computer via the preset program, and also can be done by the user manually. The results show that the more we increase the fin phase, the better the cooling performance will be and we also save material so the product cost will be cheaper.

Thermal Design and Optimization of Heat Pipe Radiator for Satellites

Satellite＇s thermal control subsystem （TCS） has to maintain components and structure within their specified temperature limits during satellite service life. TCS designers have to face the challenge of reducing both the weight of the system and required heater power while keeping components temperature within their design range. For a space based heat pipe radiator system, several researchers have published different approaches to reach such goal. This paper presents a thermal design and optimization of a heat pipe radiator applied to a practical engineering design application. For this study, a prospective communication satellite payload panel with applied passive thermal control techniques was considered. The thermal passive techniques used in this design mainly include multilayer insulation （MLI） blankets, optical solar reflectors （OSR）, selected thermal coatings, interface fillers and constant conductance heat pipes. The heat pipe network is comprised of some heat pipes embedded in the panel and some mounted on inner surface of the panel. Embedded heat pipes are placed under high heat dissipation equipments and their size is fixed; minimum weight of the radiator is achieved by a minimum weight of the mounted heat pipes. Hence, size of the mounted heat pipes is optimized. A thermal model was built and parameterized for transient thermal analysis and optimization. Temperature requirements of components in both worst case conditions （Hot case and cold case） were satisfied under optimal sizing of mounted heat pipes.

Waterways structural optimum design of electric car radiator

Thermal resistance was composed by thermal resistance of Aluminum substrate, thermal resistance of convective heat transfer and the thermal resistance of the cooling liquid. The change rule was studied through the calculation on Aluminum plate thermal resistance, thermal resistance of convective heat transfer and the thermal resistance of the cooling liquid. Its change regular- ity was simulated by toolbox In the MATLAB, and it was found that thermal resistance of convective heat transfer effect on the effi- ciency was most obvious in a certain amount of the heat and flow for thermal resistance of the Pin-fin radiator under the premise. The structural parameters of radiator were related to the size of thermal resistance.

Power Efficiency Calculation of Acoustic Energy Transmission by a Stepped-Plate Radiator

One performance measure of in-air ultrasonic radiators, such as wireless power transmission, is the power efficiency of the transducers. The efficiency of most in-air acoustic radiators is low, even at ultrasonic frequencies;however, a large radiating plate with steps introduced by Gallego-Juarez et al., can provide efficient radiation. Their in-air acoustic radiator consists of a Langevin transducer for wave excitation, a mechanical amplifier, and a stepped plate with a large radiating area. This study describes a design processing technique for a stepped-plate radiator developed for optimum energy transmission at the target point in air. The total efficiency required to transfer the acoustic energy was divided into three categories, and the design parameters of each category were calculated to maximize the efficiency. This design technique allows optimum acoustic radiation efficiency and maximum acoustic energy transmission depending on various acoustic energy transfer conditions.

Analysis and improvement of sound radiation performance of spherical cap radiator

A spherical cap radiator is one of the important parts of an underwater wide-beam imaging system. The back radiation of a traditional spherical cap radiator, which is composed of a vibrating cap and a rigid baffle, is strong and its far-field directivity function may fluctuate in big amplitude in the vicinity of the polar axis. These shortcomings complicate the processing of the reflective waves received for imaging the targets. In this study, the back radiation is weakened by adding an acoustic soft material belt between the vibrating cap and the rigid baffle. And the fluctuation mentioned above is lowered remarkably by dividing the spherical cap radiator into many annuluses and a relatively smaller spherical cap, and by controlling the phase retardations of all elements appropriately. Furthermore, the numerical experiments are carried out by the finite element method （FEM） to prove the validity of the above methods.

Finite element analysis on electron beam brazing temperature and stresses of stainless steel radiator

Based on thermal-elasto-plastic finite element theory, a two-dimensional finite element model for calculating electron beam brazing temperature and residual stress fields of stainless steel radiator are presented. The distributions of temperature and residual stress are studied. The resuhs showed that temperature distribution on brazing surface is rather uniform, ranging from 1 026 ℃ to 1 090 ℃. The residual stresses are varied from initial compressive to tensile , and the variation of residual stress is very little in total zone of brazing surface.

Experimental Research of the Radiator Thermal Performance Test Equipment and Its Application in Heating System

Radiator thermal performance test equipment plays a key role in the processing of developing a new type of heat radiator and its application products.The precise of temperature controlling,temperature measuring andflow measuring are the vital factors for a radiator thermal performance test equipment.Based on the above back-ground,this paper improves the measurement and control system of radiator thermal performance test equip-ment,which improves the accuracy of the radiator thermal performance test equipment.This paper also optimizes the software and hardware system simultaneously so as to improve the precision of the auto-test system of test equipment.Theflow rate ranges from 175 kg/h to 178 kg/h under different conditions.The average is 176.5 kg/h and the deviation rates are from 1.62%to 1.97%.The heat produced under various conditions is different.The maximum is 4.3 kW and the minimum is 4.2 kW for condition 1,the maximum is 3.3 kW and the minimum is 3.2 kW for condition 2 and the maximum is 1.95 kW and the minimum is 1.89 kW for condition 3.However,the deviation rate is about 2.9%,which shows that the device has high stability and high precision.This paper studies a new electronic heat cost allocate meter test method by radiator thermal performance test equipment at the same time.This paper tests temperature changes through four measures points and gets a result appeared as a heat backup which should be avoided when using in the test of electronic heat cost allocate meter.Some experiences and references could be gained for further research in the heating system from this test and research.

Carbon Black and Multi Wall Carbon Nanotubes Loaded Polyurethane Foam Composite Flexible Thermal Radiator

Carbon black (CB) or multi walled carbon nanotubes (MWCNT) loaded polyurethane conductive foams are used as heaters, electrodes, radar absorbers and shielding. This paper discusses the performance of an innovative flexible thermal radiator (FTR) constructed with CB filled or MWCNT filled conductive foam and powering electrode structure constructed with textiles manufacturing process (knitting, weaving or nonwoven). Silver (Ag) yarns are used for the powering electrodes construction. This paper discusses the construction, electro-thermal analysis, performance and applications of FTR. Also this paper compare the thermal and electrical characteristics of CB filled and MWCNT filled FTRs. The electro-thermal model is simulated by using finite element methods.

Radiator Vibration Fatigue Analysis

This paper is the second step of our work. The first step presents a set of parametric studies performed on automotive radiators by designing different heat exchanger models. The analysis focuses on the cooling performance for automobile radiator by changing several dimensions of the radiator fin phase (P2.5, P2.4, P2.3, P2.2, and P2.1) as well as the importance of coolant flow lay-out on the radiator global performance [1]. The second step consists on the study of the vibration fatigue of the sample with the best heat dissipation performance we design (radiator P2.1). We use Hyper Mesh to proceed with the finite element model. Frequency response analysis is solved by using MSC. Nastran (MSC. MD. Nastran. v2010.1.3-MAGNiTUDE), fatigue durability ana-lysis by using MSC Fatigue. In this experiment, the frequency response of the unit load (the unit load is 1 g) is analyzed. Based on the analysis of the frequency response of the unit load, the fatigue life of the radiator is analyzed by the PSD (power spectral density) curve and the S-N curve. From our experiments results, we observe that the radiator we design meets the international requirements of fatigue vibration under automobile normal working condition.

Effects of Heat Exchange Tube Structural Parameters on Performance of Vehicle Radiator

In order to improve the performance of vehicle radiators, a two-dimensional heat transfer steady-state model of the radiator was set up. The influence of the structural parameters (axial ratio) of the heat exchange tube on the windward side on the heat transfer performance of the radiator was studied. With the increase of the axial ratio of the heat exchange tube on the windward side, the heat exchange capacity of the heat exchange tube surface slightly decreases. The heat exchange area increases significantly, which increases the total heat exchange of the radiator and improves the heat transfer performance of the radiator. When the axial ratio increases from 1.0 to 2.0, the average surface heat transfer capacity decreases from 5664.16 W/m2 to 5623.57 W/m2.

Application of Technology of Additive Manufacturing in Radiators and Heat Exchangers

Radiators and heat exchangers play a key role in the long-term and stable operation of the equipment. The emergence of additive manufacturing technology has released the freedom of design, enabling many innovative structures of radiators and heat exchangers to be manufactured. The paper reviews the application of additive manufacturing in new radiators and heat exchangers. The technology of additive manufacturing boosts the development of new radiators and heat exchangers, which improves heat dissipation performance and heat exchange efficiency. This paper will provide a new idea and method for the development of radiators and heat exchangers via the application of additive manufacturing.

Thermomechanical and Flow Analysis of a Typical Truck Radiator Using PTC-Creo

In automobile engines,it is commonly known that the proper removal of the excess heat,resulting from internal combustion,is of high significance in the prevention of numerous negative consequences.In this regard,the radiator has a pivotal role as the main component of the engine’s cooling system.Hence,its design and analysis are highly important,requiring more comprehensive failure and flow investigations.In this work,a Scania radiator is examined under the thermal and mechanical loads,followed by its analysis under the combined thermomechanical loading.Then,the flow characteristics,including the velocity,pressure,and enthalpy,are studied.In this regard,PTC-Creo software is utilized.The results demonstrate that thermal stress causes seven times more displacement than a mechanical one.When they are combined,this value reaches 1.5 mm.Also,the max­imum failure index value of the Tresca theory is around 4.58,observed at the inlet side of the radiator.Besides,this paper indicates that the PTC-Creo can be considered a reliable and economical tool for the simulation of industrial applications,such as the considered radiator of a heavy-duty cooling system.

Dynamic interaction of an eccentric multipole cylindrical radiator suspended in a fluid-filled borehole within a poroelastic formation

Acoustic radiation and the dynamic field induced by a cylindrical source of infinite extent, undergoing angularly periodic and axially-dependent harmonic surface vibrations, while eccentrically suspended in a fluid-filled cylindrical cavity embedded within a fluid-saturated porous elastic formation, are analyzed in an exact manner. This configuration, which is a realistic idealization of an acoustic logging tool suspended in a fluid-filled borehole within a permeable surrounding formation, is of practical importance with a multitude of possible applications in seismo-acoustics. The formulation utilizes the novel features of Biot dynamic theory of poroelasticity along with the translational addition theorem for cylindrical wave functions to obtain a closedform series solution. The basic dynamic field quantities such as the resistive and the reactive components of the modal acoustic radiation impedance load on the source in addition to the radial and transverse stresses induced in the surrounding formation by an eccentric pulsating/oscillating cylinder in a water-filled borehole within a water-saturated Ridgefield sandstone medium are evaluated and discussed. Special attention is paid to the effects of source eccentricity, excitation frequency, and mode of surface oscillations on the modal impedance values and the dynamic stresses. Limiting cases are considered and good agreements with available solutions are obtained.

Non-uniform operative temperature distribution characteristics and heat-source-controlled core-area range of local heating radiators

Heating the whole space,which is currently used in northern China,leads to high energy consumption and substantial pollution.A transition to local heating has the potential to help address this problem.In this paper,the effects of radiator-related parameters(position,power,and size)and room-related parameters(aspect ratio and height)on local heating were studied.Two evaluation indices,the effective coefficient of operative temperature(OTEC)and the effective coefficient of local heating(LHEC),were proposed.In addition,the heat source-control core-area(HSCCA)was proposed,and the effect range of heat sources in the space was evaluated by the attenuation of operative temperature.The findings demonstrated that the radiator position has a greater influence on local heating than size.When the position of the radiator was changed from"close to the inner wall"to"close to the outer wall",the LHEC(the interior one-quarter of room is a local heating zone)was found to decrease by 73%.The size of the radiator,which is close to the inner wall,doubled or quadrupled,and the LHEC increased by 9%and 18%.Moreover,rooms with a larger aspect ratio or small room height were found to be the most optimal for local heating applications.The area of the HSCCA decreased as the position of the radiator approached the outer wall.The findings of this study can be used as a design reference for the radiator when the heating mode changes from"full-space heating"to"local heating".