Plate Temperature Research Articles

Effect of Hot Dip Plating Process Parameters on Microstructure and Properties of Zinc–10%Aluminum–Mischmetal Alloy Coated for Bridge Cable Steel Wire

In this work, the effect of the hot dip plating process on the microstructure and properties of zinc–10%aluminum–mischmetal (Zn-10Al-MM) alloy coated for bridge cable wire was studied by changing the hot dip plating temperature, time, and cooling mode. An optical microscope was used to observe the microstructure of the coating and steel wire at low power; a GeminiSEM300 field emission scanning electron microscope was used to observe the microstructure of the coating and steel wire at high power. The hot dip planting temperature is 450 °C, the hot dip plating time is 30 s and 45 s, whether water cooling or air cooling, the hot dip coating structure is relatively uniform, and the grain size is small, the hot dip coating thickness is thick. The coating with 450 °C, 45 s, and the water-cooling process has the highest tensile strength. The corrosion resistance of the hot dip coatings under different processes is higher in the salt spray test. Based on the results of the electrochemical test and salt spray test, the best corrosion resistance of the coatings under 450 °C, 45 s, and the water-cooling process is obtained.

Quantifying thermal strain of steel plate subjected to constant temperature by distributed fiber optic sensors

Abstract Effective strain measurement tools for steel structure at high temperature are limited due to a significant gap in measurement science. This study aims to experimentally and numerically investigate the effectiveness and limitation of Rayleigh scattering based, distributed fiber optic sensors (DFOS) without coatings for measuring the temperature and strain of a steel plate subjected to a local constant temperature. The DFOS were bonded to the steel plate by an epoxy with different bond lengths to measure coupled strain and temperature effect, while the DFOS near the end of the epoxied segment measured the temperature effect only for temperature discrimination. It was found that the DFOS accurately measured the temperature and strain of the steel plate with different bond lengths of the epoxy, as compared to the thermocouple temperature and thermal-induced strain, respectively. The maximum strain (or temperature) that the DFOS without coatings could measure for the steel plate was less than 1600 $\mu \varepsilon$ (or 150${}^{\circ}\textrm{C}$). Moreover, a local finite element model with the calibrated elastic modulus of the epoxy subjected to a uniform temperature field well captured optical fiber strains in the elastic stage. From parametric studies, the effect of the thermal expansion coefficients and elastic moduli of the optical fiber, epoxy, and host material as well as any initial defect between the optical fiber and epoxy on the strain transfer coefficient was investigated. The elastic modulus of epoxy within 100 MPa and the rectangular cross-section of epoxy (0.5 mm thick and 4 mm wide) could achieve a strain transfer coefficient of 0.997, while the initial defect had a similar effect on the strain transfer to the protective coating. The normal-distribution epoxy shape was designed for guiding robot assisted intelligent instrumentation and construction in the future.

Sensitivity Analysis of Frost Deposition in Turbulent Flow over a Cold Plate using Direct Numerical Simulation

We use a recently-developed, turbulence-informed physics-based model to study frost buildup over a flat plate subjected to turbulent flow. The plate temperature is held fixed but varied across simulations in the range −10∘C≤Tp*≤−5∘C. Similarly, the free-stream temperature and humidity ratio are also held fixed but varied across simulations in the range 0∘C≤T∞*≤20∘C and 3.77×10−3≤w˜∞≤1.47×10−2, respectively. We find the Nusselt and Sherwood numbers, when scaled by the frost surface to free-stream temperature and humidity ratio difference, respectively, to become independent of free-stream temperature and humidity ratio as well as plate temperature. The scaling can be used in conjunction with the frost layer conservation equations of mass and energy to provide an estimate for the temporal evolution of the frost layer under turbulent flow conditions for a range of plate temperatures as well as free-stream temperatures and humidity ratios. For an initial shear Reynolds number of Re=180, we find the heat and mass transfer rates to be enhanced by about a factor of three compared to laminar flow conditions. We additionally conduct a sensitivity analysis on the frost layer density and thermal conductivity empirical correlations, as well as the frost layer Schmidt number. The latter parameterizes lateral frost diffusion and must be obtained from experiments. For the cases considered, we find the frost buildup to be only sensitive to the frost density correlation.

Evaluation of the Patternability of Fibre-Based Materials with Converting Experiments

Paperboard based packaging products are renewable alternatives for packages made traditionally from oil-based polymer materials and can be used for packaging of various products [1]. Embossing is used in packaging solutions to increase the functionality and appearance of the products. It can also be used to increase product safety by improving distinctiveness and identifiability of packages [2]. The aim of the study was to evaluate the patternability of various fibre-based materials. It was desired that the accuracy and details of the embossed pattern would be the same in all samples, regardless of their different material properties. The realization of this was evaluated by several analyses related to the performance of the materials in the embossing process. Eleven different sample materials were collected for the experiments so that the patternability could be studied extensively. The common denominator of the materials selected for testing was that they were all fibre-based paper and paperboard materials used in the packaging industry. Set of embossing tools were developed, and precision machined from brass, for the experiments. A laboratory scale mechanical embossing device was utilized in modification of sample surfaces to study patternability of selected fibre-based sample materials. The main variables in the forming experiments were pressing force and tool temperature. The samples were observed primarily visually - with the naked eye, with a scanning electron microscope and a 3D-profilometer which was used in the topography analysis of the achieved patterns. The results of the embossing test series confirmed that the height of the pattern increased as a function of pressing force and plate temperature and spring back occurred in all materials after the tool plates opened. It was deduced that the pattern dimensions of the embossing plate somewhat determined the achievable pattern height in the fibre-based sample materials, but the amount of springback did not change as a function of material thickness. Despite this finding, it was consistent that the amount of spring back was regularly reduced with higher tool temperatures. The optimization study of the magnitude of the forming force showed that excessive use of force is not required, which is beneficial in reducing the risk of material damage during processing and adjustment of embossing devices. All samples differing significantly from each other were found to be suitable for embossing, indicating that patterns such as those tested could be added to a variety of packaging applications.

Improvement of Package Properties with Formed Functional Surface Features

Paperboard package properties can be improved by embossing functional features on package surfaces. Embossing is used in package manufacturing as an additional tool to improve the appearance of the packages. It can also be used to increase product safety by improving functionality and identifiability of packages. Creation of features directly on the base material without implementing additional components improves the sustainability level of package applications. To evaluate functionality of features, such as protective surface patterns, in the applicable practice, the following steps need to be gone through; design phase, tool manufacturing phase, pattern production phase and analysis phase. Bespoken toolsets were designed and manufactured to form a protective frame around commercial radio-frequency identification tag (RFID). The essential process parameters in the embossing experiments were the pressing force and the plate temperature which were optimized in preliminary tests. Methods for evaluating the performance of created embossed patterns were wear testing of package surfaces, topography measurement with a 3D profilometer and SEM-imaging for more detailed analysis. The results show that embossing is a suitable manufacturing method for creating targeted functional features on paperboard surfaces. With the formed surface features, the functionality of the packages was improved by protecting the identification labels.

Validation of the Cooling Model for TMCP Processing of Steel Sheets with Oxide Scale Using Industrial Experiment Data

To verify the mathematical model of the water-jet cooling of steel plates developed by the authors, previously performed experimental studies of the temperature of the test plates in a roller-quenching machine (RQM) were used. The calculated temperature change in the metal as it moved in the RQM was compared with the readings of thermocouples installed at the center of the test plate and near its surface. The basis of the model is the dependence of the temperatures of the film, transition and nucleate boiling regimes on the thickness of the oxide scale layer on the cooled surface. It was found that the model correctly accounts for the oxide scale on the sheet surface, the flow rates and combinations of the RQM banks used, the water temperature, and other factors. For all tests, the calculated metal temperature corresponded well with the measured one. In the experiments with interrupted cooling, the calculated temperature plots repeated the characteristic changes in the experimental curves. The main uncertainty in the modeling of cooling over a wide temperature range can be attributed to the random nature of changes in the oxide scale thickness during water cooling. In this regard, the estimated thickness of the oxide scale layer should be considered the main parameter for adapting the sheet temperature-control process. The data obtained confirm the possibility of effective application of the model in the ACS of industrial TMCP (Thermo-Mechanical Controlled Process) systems.

Dynamic performance analyses and optimization studies on air dehumidifiers using multi-stage desiccant plates

• Dynamic air dehumidification processes of a desiccant plate (DP) were studied. • Three causes for the generation of ineffective sections are found. • For the dehumidifier with multi-stage DPs, recommended stage number is 2. • An advanced dehumidifier is proposed, ineffective DPs of which can be replaced. • Effective working period of the advanced dehumidifier is extended by 2.2%∼34.8%. In this study, a novel transient air dehumidifier that can meet the dehumidification demands at places without a constant energy supply and uses multi-stage desiccant plates was proposed. Based on the simulation methods, parametric and optimization studies were carried out to extend the effective working duration. First, the air handling processes, transient temperature and humidity distribution fields of a typical desiccant plate were investigated. The results indicated that there are three reasons for the generation of ineffective dehumidification sections. To reduce the proportion of the ineffective sections and to increase the effective working duration, parametric analyses were carried out on the desiccant plate, considering factors such as the initial water content ( W ini ), inlet air humidity ratio ( ω a,in ), and length of the desiccant plate. The results show that, if the required outlet humidity ratio ( ω ∗ ) is lower than 12–13 g/kg, W ini = 0.1 kg/kg is preferred for ω a,in between 15 and 19 g/kg. Subsequently, a dehumidifier with multi-stage desiccant plates (original dehumidifier) was designed, and the optimized stage number for different total thicknesses of desiccant plates was investigated to improve the dehumidification performance. When ω ∗ is 10 g/kg, the recommended stage number is two. Finally, an advanced dehumidifier is introduced in which an ineffective desiccant plate can be replaced with a new desiccant plate. For the advanced dehumidifier, the proportion of ineffective sections can be effectively reduced by 14.6%–93.2%, and the effective working duration can be extended by 2.2%–34.8%, compared to the original dehumidifier that has the same total thickness as the desiccant plates.

Operando X-ray diffraction study of thermal and phase evolution during laser powder bed fusion of Al-Sc-Zr elemental powder blends

Elemental powder blends are an emerging alternative to prealloyed powders for high-throughput alloy design via additive manufacturing techniques. Elemental Al+Sc(+Zr) powder blends were processed by laser powder bed fusion into Al-Sc and Al-Sc-Zr alloys, with operando X-ray diffraction at the Swiss Light Source extracting the structural and thermal history of the process. The pure Sc and Zr particles were found to react with the molten Al pool at 550–650 °C, well below their respective melting temperatures. Various scan areas (1 × 1, 2 × 2, 4 × 4, and 8 × 2 mm 2 ) were studied to compare (i) the base plate “preheating” effect caused by prior laser scans, (ii) the return temperature reached after the melting scan and before the following scan, (iii) the initial cooling rate immediately after solidification, and (iv) the time spent in the “intrinsic heat treatment range”, defined as 300–650 °C, where secondary Al 3 (Sc,Zr) precipitation occurs. Microstructural analysis of the as-built samples show 110–140 nm L1 2 -Al 3 (Sc,Zr) primary precipitates at the bottom of the melt pool. The 1 × 1 mm 2 samples exhibit the most elongated grains (long axis of 10 ± 5 µm), which correlates with the highest build plate temperature and the slowest initial cooling rate (3–5 × 10 5 K/s). In comparison, the 4 × 4 mm 2 samples exhibit the smallest equiaxed grains (2 ± 0.6 µm), corresponding to the lowest build plate temperature and the fastest initial cooling rate (6–7 × 10 5 K/s). These results indicate the need for establishing a minimum feature size during part design, or for modifying the laser parameters during processing, to mitigate microstructure and performance differences across features of different sizes.

On the differential effect of temperature on the Nusselt-Rayleigh relationship in free convection

The aim of and inspiration behind this paper was to explain the reasons, also observed by other researchers, of the discrepancy in the results of experimental free convection, which for small Rayleigh and Nusselt numbers in the initial phase of research can sometimes reach several hundred percent. These discrepancies decrease with increasing heating power and plate surface temperature, in proportion to the increase in Ra and Nu, reaching typical values for this type of research. To explain this phenomenon, a comprehensive theoretical and experimental analysis of the influence of the physical properties of a fluid (air and water) as well as primary (tw and t∞) and secondary (tav and Δt) temperatures on the Rayleigh number was carried out. The impact was found to be unequal. The plate temperature tw is of greater importance, which is much higher than the much lower and almost constant temperature t∞ of the undisturbed area, especially since it causes convective movement, generating differences in fluid density and thus driving the phenomenon. Similarly, the direct contribution of the temperature difference Δt to Ra suggests that it has a greater influence on convective heat transfer than the average temperature of the medium tav.By analysing the effect of each of these temperatures separately, it was possible to show that their mutual, compatible or opposite interaction (tw/t∞) causes a different scattering of results, or may even lead to unusual Rayleigh numbers (Ra temperature dualism). This study led not only to a better understanding of the phenomenon, but even to a prediction of its unusual behaviour, unheard of in typical experimental studies of free convection.For example, if we consider the theoretical convective heat transfer from a plate l = 0.15 m in air in the context of the interaction of tav and Δt, it turns out that for the same Δt = 40 K, the Rayleigh number may assume, depending on tav = (tw + t∞)/2, different values. So, for tw = 50 °C, t∞ = 10 °C and tav = 30 °C, Ra = 1.213.107, whereas for tw = 90 °C, t∞ = 50 °C and tav = 70 °C it is ≈ 1.7 times smaller (Ra = 0.687.107). This hypothetical phenomenon, unheard of in typical experimental studies, which could occur, and maybe even does occur in smelting, thermal energy, etc., forces us to think about the values of Nusselt numbers, heat transfer coefficients and heat fluxes for these two cases. This lies beyond the scope of the present paper, but it is a topic for possible future research.

Unsteady MHD free convective flow past a moving vertical plate in a porous medium with radiation and chemical reaction including arbitrary thermal and solutal ramped condition

AbstractThe motive behind this investigation is to examine the unsteady magnetohydrodynamics free convective fluid flow with heat and mass transfer of a viscous, incompressible flow past a moving upright plate in a porous medium with radiation, chemical reaction, arbitrary thermal, and solutal ramped condition. An analytical solution for momentum, energy, and concentration equations is accomplished by implementing the Laplace transformation technique. The influence of different nondimensional parameters on fluid velocity, temperature, and concentration along with skin friction and rate of heat transfer as well as mass transfer at the plate are exhibited graphically. It can be spotted that both the concentration and temperature field decrease for rising values of the ramped parameter, radiation parameter, chemical reaction parameter, and Schmidt number. Moreover, it is detected that the fluid velocity drops in the case of the isothermal plate, and velocity upsurges for the ramped plate temperature. Investigation simulates that the rate of heat transfer, as well as rate of mass transfer, is escalated on hiking radiation parameter.

CFD Impingement Flow Study on Temperature Profile of Concave Plate

All the aircraft are equipped with an anti-icing system to prevent ice accretion on the body of the aircraft. The anti-icing system is important because ice accretion degrades the performance of the aircraft and may cause aircraft crashes. Piccolo tube Anti-icing system uses the impingement hot air and creates hotspot on nacelle lip-skin and edges of wings. The temperature distribution caused by the impingement of hot air must be studied to get a better design of the anti-icing system. The skin geometry shape affects hot airflow behavior in the impingement vicinity, hence influences temperature distribution on wing skin and nacelle lip-skin. Thus, the CFD simulation of the hot air impingement air various concave curvature radius was conducted by using ANSYS Fluent 19.2. The result shows the temperature contour has been plotted from the software. Correlation between Nusselt number on impingement point and Reynolds number was successfully done as the validation. Increasing the Reynolds number increases the dimensionless temperature of the concave plate. Temperature is 0.147125 has been recorded as the highest dimensionless temperature under the set of an air temperature of 43°C, Reynolds number of 4070, and 300mm curvature radius. Besides that, increases in heat dissipation decrease the dimensionless temperature of the plate with the curvature radius also decreases. The dimensionless temperature increases from 0.138747 to 0.142316 when the curvature radius increases from 150mm to 300mm.

МАГНЕТРОНДЫҚ ЫДЫРАТУ ӘДІСІМЕН СИНТЕЗДЕЛГЕН ТИТАН НИТРИДІ ПЛЕНКАЛАРЫНЫҢ ҚҰРЫЛЫМЫ МЕН ҚҰРАМЫ

The article defines the conditions for obtaining the necessary composition of TiN films used as a diffusion barrier in solar cells. The conditions for obtaining the required thickness of the titanium nitride film are also determined. It was found by X-ray diffraction that the resulting titanium nitride film has a polycrystalline structure. As a result of a number of experiments, the conditions for obtaining atitanium nitride film with the required thickness of 75 nm and density (composition Ti0.57N0.43) were determined: magnetron power-690 W, pressure of the Ar-N2 mixture-0.54 Pa, nitrogen gas consumption 0.9 l/h, argon gas consumption 0.5 l/h, plate temperature 111 °C, deposition duration -320 s.

A distinctive Pb-Sn semi-solid additive manufacturing using wire feeding and extrusion

Based on the semi-solid forming technology, the semi-solid additive manufacturing platform was built in this study, and the forming process was carried out with Pb-Sn wire as raw material. The results showed that when z-axis moving distance of monolayer stacking is 4.2 mm, extruder head temperature reaches 240 °C and heating plate temperature reaches 160 °C, the microstructure is composed of spherical grains of Pb solid solution with average diameter of 13.4 μm and low melting point Sn phase distributed at the grain boundary, the corresponding overlap surface curvature is 0.429 mm−1; The macro morphology also showed the best characteristics with forming effective degree of 0.869 and forming layer height ratio of 1.004. The mechanical properties of semi-solid additive manufacturing sample with optimized processing parameters were tested, the vertical and horizontal tensile strength of the sample are 44.2 and 47.8 MPa respectively, and the elongation in the vertical direction of sample (29.1 %) is significantly higher than that (20.1 %) in the horizontal direction because of double necking phenomena, this deformation mechanical can be explained by the existence of several bonding areas in gauge segment and soft of bonding areas due to enrich of Sn. Finally, Pb-Sn parts with different shapes were formed. This study provides a basis for the further development of semi-solid additive manufacturing for aluminum.

MODELLING OF STEEL TO TIMBER JOINT EXPOSED TO FIRE

The paper presents an investigation on a timber joint with an inserted steel plate under fire exposure. According to standard EN 1995-1-2 (2004), the fire resistance of unprotected timber joints is limited to 30 min. However, several studies have shown that these joints can achieve higher fire resistance comparing to values given in the standard. In order to verify this, a numerical model of bolted steel-timber joint at elevated temperature was created. The presented model is focused on heat transport in the joint, which is affected by the presence of the steel plate and bolts. The model was validated on experimental results taken from literature and on measurement from a fire tests conducted in a medium-sized furnace. Considering the results of validation, the model has a good ability to predict residual cross-section, temperature of steel plate and bolts and temperature of timber elements. The results of validated numerical model are also compared to the analytical model.

Monitoring of Heated Wire Humidifier Hygrometric Performances With Heater Plate Temperature.

Under-humidification and associated complications may occur with heated humidifiers. Hygrometric performances of heated wire humidifiers are reduced by high ambient and high outlet ventilator temperatures. Currently, there is no reliable monitoring tool to evaluate humidification performances of heated wire humidifiers in the daily practice. We sought to demonstrate the relation between humidity delivered by heated wire humidifiers and different parameters that could be used to monitor humidity of gas delivered to subjects. On a bench test, we measured heater plate temperature, inlet chamber temperature, and delivered humidity with MR850 system. Temperature displayed on the humidifier was also recorded. The measurements were performed at different ambient temperatures and five minute ventilation levels (5, 7.5, 10, 12.5, 15 L/min). Inlet chamber temperatures varied from 20-40°C. In each condition, hygrometric measurements with the psychrometric method were performed at steady state. We performed 279 measurements at steady state including all conditions. We found a good correlation between heater plate temperature and absolute humidity delivered (R2 = 0.82). This relationship was hardly affected by ambient temperature, but minute ventilation had more effect. For different minute ventilations, the correlation between heater plate temperature and absolute humidity delivered was very good with coefficient of determination R2 from 0.87-0.98. Heater plate temperature > 62°C was a good predictor of absolute humidity delivered > 30 mg H2O/L (area under the curve = 0.96, sensibility 79%, specificity 94%). No correlation existed between humidity delivered and the outlet chamber temperature (displayed on the humidifier). In this bench study, we have shown a good correlation between heater plate temperature and humidity delivered with a heated wire humidifier. This means that a "hidden" hygrometer is built into the heated wire humidifier. Heater plate temperature should be used as a surrogate of humidity to improve the humidification monitoring.

On thermal management of pouch type lithium-ion batteries by novel designs of wavy minichannel cold plates: Comparison of co-flow with counter-flow

The liquid cooling technique is the most preferred technique among the common methods of battery thermal management (BTM) due to its greater compactness and better efficiency. The temperature uniformity within batteries, mainly when they operate under extreme conditions (thermal runaways) is of utmost importance because a uniform temperature distribution can noticeably affect the performance, safety, and lifetime of batteries. Concerning this issue, novel wavy minichannel cold plates are proposed to establish better thermal management and temperature uniformity in pouch type lithium-ion batteries. The considered cases have variable wave amplitudes, which are varied in each wavelength of the wavy minichannels. These cases are investigated for the co-flow and the counter-flow patterns to improve conventional wavy cold plate temperature gradient problems in the laminar flow regime. The results indicate that replacing the conventional wavy cold plate with novel designs can improve temperature uniformity and decline the corresponding factor by 38.7%. It is found that a cold plate with the counter-flow pattern has a better temperature uniformity than the case with the co-flow pattern. Moreover, it is worth mentioning that the temperature distribution and uniformity of the conventional model are considerably influenced by the flow pattern compared to the novel cases. Using a counter-flow pattern in the conventional case leads to 73.1% decline in the maximum temperature difference compared to the co-flow pattern.

The Effect of Solution Casting Temperature and Ultrasound Treatment on PEBAX MH-1657/ZIF-8 Mixed Matrix Membranes Morphology and Performance.

Approximately two-thirds of anthropogenic emissions causing global warming are from carbon dioxide. Carbon capture is essential, with membranes proving to be a low cost and energy-efficient solution to alternative technologies. In particular, mixed matrix membranes (MMMs) can have higher permeability and selectivity than pure polymer membranes. The fabrication conditions affect the formation of defects within the membranes. In this work, MMMs were created using a PEBAX MH-1657 polymer and a ZIF-8 filler. The effect of casting plate temperature, varying from −5 °C to 50 °C, and the effect of ultrasound treatment time (80–400 min) and method (filler solution only, filler and polymer combined solution only and filler solution followed by combined solution) were investigated, aiming to reduce defect formations hence improving the performance of the MMMs. SEM images and permeation tests using pure CO2 and N2 gas, replicating flue gas for carbon capture, were used to investigate and compare the membranes morphology and performance. The results indicated that the MMMs maintained their permeabilities and selectivities at all tested casting temperatures. However, the neat PEBAX membranes demonstrated increased phase separation of the polyamide and polyether oxide phases at higher temperatures, causing a reduction in permeability due to the higher crystallinity degree, confirmed by DSC experiment. The MMMs fabricated at low ultrasound times displayed a large amount of aggregation with large particle size causing channeling. At high ultrasound times, a well-dispersed filler with small filler diameters was observed, providing a high membrane performance. Overall, defect-free membranes were successfully fabricated, leading to improved performance, with the best membrane resulting from the longest ultrasound time reaching the Robeson bound upper limits.

ZnO Piezoelectric Films for Acoustoelectronic and Microenergetic Applications

Zinc oxide is one of the most popular materials for acoustoelectronic sensors and vibro-piezo-transducers used in nano-piezo-generators. In the present paper, thick piezoelectric ZnO films are fabricated on both sides of various substrates using magnetron sputtering technique. It is shown that the main problem for double film deposition is the difference in thermal expansion coefficients of the ZnO films and the substrate materials. The problem is solved by decreasing the plate temperature up to 140 °C, reducing the growing rate up to 0.8 ± 0.05 μm/h, and diminishing the oxygen content in Ar mixture up to 40%. Using the modified sputtering conditions, the ZnO films with thickness up to 15 μm, grain size 0.3 μm, and piezoelectric module as large as 7.5 × 10−12 C/N are fabricated on both faces of quartz and lithium niobate plates as well as on flexible polyimide flexible film known as Kapton. The films are characterized by chemical composition, crystallographic orientation, piezoelectric effect, and acoustic wave generation. They are applied for vibro-piezo-transducer based on flexible ZnO/Kapton/Al/ZnO/Al structure. When the structure is mechanical excited, the variable electric voltage of about 35 mV is generated. The value of the voltage is sufficient for an unstable energy source used in autonomic micro-energetic energy-store systems.

Fishtail Divertor and its basis surface thermal load bearing performance

Fishtail Divertor (FTD) configuration is a dynamic magnetic field divertor configuration that uses the AC coil installed on the back of the divertor target plate to realize the swing of the strike line. The most important driving force of FTD configuration design is to improve the thermal bearing performance of divertor target plate. Under FTD configuration, the maximum temperature of divertor target plate will eventually reach a dynamic equilibrium state, and it have an obvious jump at both ends of the swing area. With the increase of the swing frequency, FTD configuration can more effectively improve the thermal load bearing performance of the divertor target plate. However, if only to alleviate the steady-state heat load, the swing frequency of FTD no need to be higher than 100 Hz. FTD configuration has engineering application prospects in future fusion reactors. Under a swing distance of 10 cm and a thermal load condition of qp=100MW/m2 and λT=5mm (steady state), Triangular wave Fishtail Divertor (TFTD) swing frequency exceeds 5 Hz or Sine wave Fishtail Divertor (SFTD) swing frequency exceeds 20 Hz, the maximum temperature of target plate can be lower than 900 K. At the same conditions expect the swing frequency is 100 Hz, the maximum temperature under TFTD and SFTD can lower than 700 K and 800 K respectively.

Experimental study on photovoltaic/thermal system performance based on microencapsulated phase change material slurry

ABSTRACT Microencapsulated phase change material slurry (MPCMS) as working fluid has a certain potential to enhance the PV/T system capability. An experimental study was carried out to explore the impacts of water flux (0–0.0085 kg/s) and MPCMS mass concentration (0–5%) on electrical properties and thermal properties of the PV/T system by using a halogen tungsten lamp to simulate solar radiation. The results reveal that as the water flux is from 0.0024 kg/s to 0.0085 kg/s, the PV plate temperature decreases by 3.61°C, and the electrical efficiency increases by 0.3%. The electrical efficiency increases by 4.92% for every 0.1 kg/s increment in the cooling water flux. The best thermal efficiency and primary-energy efficiency are obtained at a water flux of 0.0045 kg/s. The electrical exergy raises with the increment of water flux, whereas the thermal exergy and the exergy efficiency decline with the flux increment. Compared to pure water, the thermal efficiency and exergy efficiency are improved by using MPCMS, and the primary-energy efficiency and the exergy efficiency are increased by 1.85% and 12.12%, separately. It is proved that the MPCMS effectively improves the PV/T system performance.