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.

Improvement of microstructure and mechanical properties of Al−Cu−Li−Mg−Zn alloys through water-cooling centrifugal casting technique

The microstructure and mechanical properties of as-cast Al−Cu−Li−Mg−Zn alloys fabricated by conventional gravity casting and centrifugal casting techniques combined with rapid solidification were investigated.Experimental results demonstrated that compared with the gravity casting technique,the water-cooling centrifugal casting technique significantly reduces porosity,refinesα(Al)grains and secondary phases,modifies the morphology of secondary phases,and mitigates both macro-and micro-segregation.These improvements arise from the synergistic effects of the vigorous backflow,centrifugal field,vibration and rapid solidification.Porosity and coarse plate-like Al13Fe4/Al7Cu2Fe phase result in the fracture before the gravity-cast alloy reaches the yield point.The centrifugal-cast alloy,however,exhibits an ultra-high yield strength of 292.0 MPa and a moderate elongation of 6.1%.This high yield strength is attributed to solid solution strengthening(SSS)of 225.3 MPa,and grain boundary strengthening(GBS)of 35.7 MPa.Li contributes the most to SSS with a scaling factor of 7.9 MPa·wt.%^(-1).The elongation of the centrifugal-cast alloy can be effectively enhanced by reducing the porosity and segregation behavior,refining the microstructure and changing the morphology of secondary phases.

Distinct MLT asymmetry of auroral kilometric radiation observed by the FAST satellite

Auroral Kilometric Radiation(AKR)is a common radio emission,which can contribute to the magnetosphere−ionosphere−atmosphere coupling.Similar emissions have been observed in all magnetic planet magnetospheres of the solar system.In this study,using observations from the FAST satellite from 30 August 1996 to 9 September 2001,the distribution of AKR in altitude=500−4500 km and invariant latitude(|ILAT|)=60°−80°has been analyzed.63045 AKR samples have been identified with~48%(52%)samples on the dayside(nightside).Of considerable interest,there is a distinct MLT asymmetry with the high occurrence rate in MLT=05−08 and 18−22(02−05 and 12−17)in the northern(southern)hemisphere.The distinct MLT asymmetry is associated with the direction of Bxof the interplanetary magnetic field.In addition,the occurrence rate on the nightside clearly increases as the index increases.This study further enriches theAE.information and understanding of AKR in the magnetosphere as well as other similar radio emissions.

Impact of Pollutant Concentration and Particle Deposition on the Radiative Flow of Casson-Micropolar Fluid between Parallel Plates

Assessing the behaviour and concentration of waste pollutants deposited between two parallel plates is essential for effective environmental management.Determining the effectiveness of treatment methods in reducing pollution scales is made easier by analysing waste discharge concentrations.The waste discharge concentration analysis is useful for assessing how effectively wastewater treatment techniques reduce pollution levels.This study aims to explore the Casson micropolar fluid flow through two parallel plates with the influence of pollutant concentration and thermophoretic particle deposition.To explore the mass and heat transport features,thermophoretic particle deposition and thermal radiation are considered.The governing equations are transformed into ordinary differential equations with the help of suitable similarity transformations.The Runge-Kutta-Fehlberg’s fourthfifth order technique and shooting procedure are used to solve the reduced set of equations and boundary conditions.The integration of a neural network model based on the Levenberg-Marquardt algorithm serves to improve the accuracy of predictions and optimize the analysis of parameters.Graphical outcomes are displayed to analyze the characteristics of the relevant dimensionless parameters in the current problem.Results reveal that concentration upsurges as the micropolar parameter increases.The concentration reduces with an upsurge in the thermophoretic parameter.An upsurge in the external pollutant source variation and the local pollutant external source parameters enhances mass transport.The surface drag force declines for improved values of porosity and micropolar parameters.

New Math Model for Designing Engine Radiator

Aim To raise the H-NE math model for designing engine radiators.Methods Thismodel was founded on multi-nonlinear regression technology,and the quadratic equatingmethod was used to smooth original data.Through the sensitivity analysis about radiatoroptimization designing,some major restraints were obtained.Results Type 1301C radiator wasoptimizingly renwed by use o this model,and the new radiator is more excellent than theold one in respect of the heat transfer factor and the manufacturing cost.Conclusion Theradiation performance can be improved,the area can be reduced,and the fitting scope can bewidened if this model is used in designing radiators.

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. [

Flow Field and Temperature Field of Water-Cooling-Type Magnetic Coupling

At present, the water-cooling simulation of the water-cooled magnetic coupler is based on the water-cooled motor and the hydraulic coupler, which cannot accurately characterize the temperature distribution of the rotating watercooled coupling of the coupler. Focusing on rotating water cooling radiating, the present paper proposes simulating the water cooling temperature field as well as the flow field through the method of combining fluid-solid coupled heat transfer and MRF(Multiphase Reference Frame). In addition, taking an 800 kW magnetic coupling as an example, the paper optimizes the shape, number, cooling water inlet speed? and so on? of the cooling channel. Considering factors such as the complete machine’s temperature, and drag torque, it is proved that the cooling e ect is best when there are 36 involute curved channels and when the inlet speed is 3 m/s. Further, through experiments, the actual temperature values at six di erent positions when 50 kW and 70 kW thermal losses di er are measured. The measured values agree with the simulation results, proving the correctness of the proposed method. Further, data have been collected during the entire experimental procedure? and the variation in the coupling’s temperature is analyzed in depth, with the objective of laying a foundation for the estimation of the inner temperature rise as well as for the optimization of the structural design.

Thin film design for advanced thermochromic smart radiator devices

This paper describes the research on the materials and design methods for advanced smart radiator devices （SRDs） on large-area flexible substrates utilized on spacecraft. The functional material is thermochromic vanadium dioxide. The coating design of SRD is similar to the design of broadband filter coatings in a mid-infrared region. The multilayer coatings have complex structures. Coating materials must be highly transparent in a required spectrum region and also mechanically robust enough to endure the influence from the rigorous environments of outer space. The number of layers must be very small, suitable for the deposition on large-area flexible substrates. All the coatings are designed initially based on optical calculation and practical experience, and then optimized by the TFCALC software. Several designs are described and compared with each other. The results show that the emittance variability of the designed SRDs is great than 400%, more advanced than the reported ones.

Neutron Capture Therapy (NCT) & In-Hospital Neutron Irradiator (IHNI)——a new technology on binary targeting radiation therapy of cancer

BNCT is finally becoming ＂a new option against cancer＂. The difficulties for its development progress of that firstly is to improve the performance of boron compounds, secondly, it is the requirements of quantification and accuracy upon radiation dosimetry evaluation in clinical trials. Furthermore, that is long anticipation on hospital base neutron sources. It includes dedicated new NCT reactor, accelerator based neutron sources, and isotope source facilities. In ad- dition to reactors, so far, the technology of other types of sources for clinical trials is not yet completely proven. The In- Hospital Neutron lrradiator specially designed for NCT, based on the MNSR successfully developed by China, can be installed inside or near the hospital and operated directly by doctors. The Irradiator has two neutron beams for respective treatment of the shallow and deep tumors. It is expected to initiate operation in the end of this year. It would provide a safe, low cost, and effective treatment tool for the NCT routine application in near future.

Mathematical model on heat transfer of water-cooling steel-stick bottom electrode of DC electric arc furnace

For predicting and controlling the melted depth of bottomelectrode during the process of steelmaking, the water-cooling steel-stick electrode is taken as an example, to analyze the process ofheat transfer, then 3D mathematical model by control capacity methodis built. At the same time, the measurement on the melted depth ofbottom electrode is conducted which verified the correctness of thebuilt mathematical model. On the base of verification, all kinds ofkey parameters are calculated through the application and a series ofresults are simulated. Finally, the optimum parameters are found andthe service life of bottom electrode is prolonged.

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.

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.

Thermal analysis of an innovative flat heat pipe radiator

An innovative flat heat pipe radiator was put forward, and it has the features of high efficiency of heat dissipation, compact construction, low thermal resistance, light weight, low cost, and anti-dust-deposition. The thermal analysis of the flat heat pipe radiator for cooling high-power light emitting diode （LED） array was conducted. The thermal characteristics of the flat heat pipe radiator under the different heat loads and incline angles were investigated experimentally in natural convection. An electro-thermal conversion method was used to measure the junction temperature of the LED chips. It is found that the integral temperature distribution of the flat heat pipe radiator is reasonable and uniform. The total thermal resistance of the flat heat pipe radiator varies in the range of 0.38-0.45 K/W. The junction temperatures of LED chips with the flat heat pipe radiator and with the aluminum board at the same forward current of 0.35 A are 52.5 and 75.2 ℃, respectively.

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.

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.

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.

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.

Numerical Analysis of the Magnetic Dipole Effect on a Radiative Ferromagnetic Liquid Flowing over a Porous Stretched Sheet

The effects of a magnetic dipole on a nonlinear thermally radiative ferromagnetic liquidflowing over a stretched surface in the presence of Brownian motion and thermophoresis are investigated.By means of a similarity transformation,ordinary differential equations are derived and solved afterwards using a numerical(the BVP4C)method.The impact of various parameters,namely the velocity,temperature,concentration,is presented graphically.It is shown that the nanoparticles properties,in conjunction with the magnetic dipole effect,can increase the thermal conductivity of the engineered nanofluid and,consequently,the heat transfer.Comparison with earlier studies indicates high accuracy and effectiveness of the numerical approach.An increase in the Brow-nian motion parameter and thermophoresis parameter enhances the concentration and the related boundary layer.The skin-friction rises when the viscosity parameter is increased.A larger value of the ferromagnetic para-meter results in a higher skin-friction and,vice versa,in a smaller Nusselt number.

Selective internal radiation therapy segmentectomy:A new minimally invasive curative option for primary liver malignancies?

Transarterial radioembolization or selective internal radiation therapy(SIRT)has emerged as a minimally invasive approach for the treatment of tumors.This percutaneous technique involves the local,intra-arterial delivery of radioactive microspheres directly into the tumor.Historically employed as a palliative measure for liver malignancies,SIRT has gained traction over the past decade as a potential curative option,mirroring the increasing role of radiation segmentectomy.The latest update of the BCLC hepatocellular carcinoma guidelines recognizes SIRT as an effective treatment modality comparable to other local ablative methods,particularly well-suited for patients where surgical resection or ablation is not feasible.Radiation segmentectomy is a more selective approach,aiming to deliver high-dose radiation to one to three specific hepatic segments,while minimizing damage to surrounding healthy tissue.Future research efforts in radiation segmentectomy should prioritize optimizing radiation dosimetry and refining the technique for super-selective administration of radiospheres within the designated hepatic segments.