Analysis Of Temperature Distribution Research Articles

Temperature distribution analysis of monocrystalline photovoltaic panel for photovoltaic-thermoelectric generator (PV-TEG) hybrid application

Temperature distribution analysis of monocrystalline photovoltaic panel for photovoltaic-thermoelectric generator (PV-TEG) hybrid application

Performance Improvement of a Single PEM Fuel Cell Using an Innovative Flow Field Design Methodology

Flow fields of polymer electrolyte membrane fuel cells (PEMFCs) are used to feed reactant gases over the surface of catalyst layer homogeneously and remove byproduct, water. Optimization of the flow field design would improve homogeneity of the gas distribution and pressure drop values resulting in higher power density values. Flow field designs inspired from veins of tree leaves have been analyzed and tested. A mathematical model has been conducted for verifying the experimental results. A decrease in pressure drop and homogeneous distribution of gasses without flooding was observed with our novel designs. The dimensions of the flow channels were selected based upon tree leaves that obey Murray’s law. Semi cylindrical obstacles were fabricated on the ground to direct the gas flow to the gas diffusion layer. The effect of these obstacles was observed at high current values. The cell performance and current density–temperature distribution analysis showed performance improvement up to 42.1% in comparison with the standard serpentine design. Homogeneity of current and temperature distributions was also improved with the proposed design. Additionally, water removal was improved with the current design.

Numerical Analysis of Temperature Distributions in Single Cell of PEFC by Heat Transfer Model Considering Vapor Transfer

Numerical Analysis of Temperature Distributions in Single Cell of PEFC by Heat Transfer Model Considering Vapor Transfer

Quantitative thermal measurement by the use of scanning thermal microscope and resistive thermal probes

Scanning thermal microscopy (SThM) is the only method for thermal measurements providing spatial resolution in the nanometer range. The method combines the topographical imaging of atomic force microscopy (AFM) with the thermal characterization of samples by the use of specially designed AFM probes having a temperature sensor near the apex. Measurements can be carried out in two modes: the temperature contrast (or passive) mode and the conductance contrast (or active) mode. In the first mode, the probe is not heated and the temperature distribution on the sample surface is measured. In the second mode, there are no heat sources in the sample and the probe is heated. The probe temperature depends on the thermal conductance for the heat exchange between the probe and the sample. This thermal conductance depends on the sample thermal conductivity and probe-sample interfacial thermal resistance. If the latter is constant, the distribution of the thermal conductivity on the sample surface can be obtained. The principle of qualitative SThM is quite simple. However, quantitative measurements require rigorous analysis of temperature distribution and heat fluxes in the probe-sample system. This paper provides basic information about SThM starting from first principles, through instrumentation, characterization of probes used for measurements, general theory of the temperature, and the thermal conductivity measurements, to a few examples of practical applications of this method. Finally, perspectives and challenges for SThM based measurements are discussed.

Comparison and analysis of temperature distribution in pouch and cylindrical Li-ion battery by finite element thermal model

Comparison and analysis of temperature distribution in pouch and cylindrical Li-ion battery by finite element thermal model

Numerical Calculation and Analysis of Temperature Distribution during Ultrasonic Welding Process for NiTi Shape Memory Alloy

Numerical Calculation and Analysis of Temperature Distribution during Ultrasonic Welding Process for NiTi Shape Memory Alloy

Spatiotemporal analysis of the land surface temperature distribution over the territory of Novosibirsk city based on Landsat data

The paper discusses the applicability of Landsat 8 data for analyzing the land surface temperature distribution over the territory of Novosibirsk. The satellite data is compared with the data from ground meteorological stations. Using cloud-based systems and methods for processing time series of satellite data, a composite image of the temperature field for the territory of Novosibirsk is built; trends and anomalies in the temperature distribution in the urban area are studied. The results could be applied in urban development analysis and management of the city territory.

Analysis of electric field intensity and temperature distribution with various permittivity in supercapacitor by 3-D FEM

Analysis of electric field intensity and temperature distribution with various permittivity in supercapacitor by 3-D FEM

Multiphysics Analysis of an Axial-Flux In-Wheel Motor With an Amorphous Alloy Stator

This paper presents a novel yokeless and segmented armature (YASA) axial-flux in-wheel motor with amorphous magnetic material (AMM) stator cores for a solar-powered electric vehicle. Although this new axial-flux in-wheel motor has many advantages such as high efficiency, shorter axial length, and high power density, its working condition is complicated. In-wheel motors are usually operated in electromagnetic, thermal, and other multiphysics environments. Increasing the performance requirements of in-wheel motors, such as power density, efficiency, and reliability, requires a multiphysics design approach. The focus of this paper is on the analysis of electromagnetic characteristics, losses, temperature distribution, mechanical behavior and other characteristics of the axial-flux in-wheel motor. The back electromotive force (EMF) and electromagnetic torque of the motor with harmonic current are obtained by the 3-D finite element method (FEM). The permanent magnet (PM) eddy-current losses when using different PM shapes are studied. The equivalent thermal model of the tape-wound AMM stator segments and the windings are established, and the temperature distribution of the motor is obtained. The mechanical behavior of the stator segments and the rotor disks when the motor is eccentric and axially offset is analyzed, and the structural strength of the motor is evaluated. Finally, a prototype of the motor is fabricated, and the electromagnetic performance and temperature of the motor are tested to verify the accuracy of the multiphysics design approach.

Effects of contact pressure and interface temperature on thermal contact resistance between 2Cr12NiMoWV/BH137 and γ-TiAl/2Cr12NiMoWV interfaces

Thermal contact resistance between interfaces is an important parameter in the analysis of temperature distribution for structural components. Thermal contact resistance between heat resistant steel 2Cr12NiMoWV/aluminum alloy BH137 interfaces and 2Cr12NiMoWV/titanium alloy ?-TiAl interfaces were experimentally investigated in the present paper. The effects of contact pressure and interface tem-perature were detailed. The temperature of contacting surfaces was from 80- 250?, and the contact pressure ranged from 2-17 MPa. All experiments were conducted in ambient atmosphere. Results showed that thermal contact resistance decreases with an increment of interface temperature or contact pressure. Under the same conditions of contact pressure and interface temperature, thermal contact resistance between 2Cr12NiMoWV and BH137 interfaces is lower than that between 2Cr12NiMoWV and ?-TiAl interfaces. The temperature dependence of thermal conductivity and mechanical properties was analyzed to explain the results. Furthermore, with the piston and piston pin as the research object, steady state temperature fields were simulated in cases of considering thermal contact resistance and without considering thermal contact resistance, respectively. The results showed that the maximum temperature of the piston pin will be lower when thermal contact resistance is considered.

온도 상승에 따른 우리나라 습지식물의 기후변화 부적응 리스크 평가

Temperature increase is a major concern with regard to climate change and species survival. This study sought to assess the adaptability of wetland flora in South Korea to future temperature increases in their habitats. This risk assessment includes analysis of four vulnerability types classified and graded based on relational patterns between species’ populations and current habitat temperature. Then, the risks of future temperature changes for individual species were assessed by analyzing the vulnerability and temperature increasing speed in South Korea. The final risks were categorized into four grades: high, medium, low, and opportunity. In this study, a total of 489 wetland plants in South Korea were selected and their habitat temperature ranges were examined using current and projected future temperature data. Analysis of current habitat temperature distribution and projected future changes was performed using fine‐scale climate change data produced by the Korean Meteorological Administration. Future temperature data were projected based on two future climate change scenarios: Representative Concentration Pathway (RCP) 4.5 and 8.5. The results showed no risk to wetland plants under the RCP 4.5 climate change scenario, but under RCP 8.5, a considerable number of species were predicted to be at medium risk. Species under medium risk were mainly those inhabiting a very narrow range. It is reasonable to infer that even wetland flora thought to be less sensitive to temperature changes are not completely safe to the level of temperature increase seen under the RCP 8.5 scenario. The methodology for risk assessment introduced in this study is expected to be useful for designing adaptation strategies for species conservation in the face of climate change.

Temperature Distribution on Sticky Non Compressible Fluid Flow using DHPM Technology

This paper deals with the analysis of temperature distribution on sticky non compressible fluid flow by utilizing DHPM (Differential Homotopy Perturbation Method) for stretched and uniform heat flux. This technique is developed for solving many distributed and temperature velocities. The exact solution for temperature distribution is compared by the final scattering medium final result to get the accurate results. This technique gives approximately 80% accuracy results compared to exact results.

Numerical analysis of temperature distribution in sliding contacts of pin on disc model

Pin on disc is a tribosystem confirming to ASTM G99, is employed in this work. It consists of deformable cylindrical disc and rigid pin with friction. Coating of Inconel 712 is added on stainless steel disc and pin is made of SiC3. The FEM software ANSYS R19.1 is employed for simulation of temperature distribution produced due to friction between pin on disc. Stress distribution is calculated from result produced between pin and disc interface due to applied contact load on pin. The governing equation is mentioned in introduction section. Result showing as contact load on pin increases maximum principle stress is increases. Temperature rises in direct proportion with sliding distance and time. Simulation result validates and confirmed with experimental results.

Heat transfer analysis of different thermal oils in parabolic trough solar collectors with longitudinal sinusoidal internal fin

Parabolic trough solar collectors (PTSC) plays an important role in the heating of fluids and in the generation of electricity . In this study, heat transfer and temperature distribution analysis was carried out for the use of internal longitudinal fins with different geometries in a parabolic trough solar collector. Numerical analyzes were carried out for different Reynolds (Re) numbers (2x104-8 x104) at steady-state conditions and three different thermal oils were used as heat transfer fluid (HTF). The use of the internal fin with sinusoidal lateral surface for all types of thermal oil increased the heat transfer and made the temperature distribution in the fluid more uniform. The highest thermal enhancement factor was occurred for Syltherm 800 oil and sinusoidal fin geometry. With the use of Syltherm 800 oil, the thermal enhancement factor () increased by 40% and 44% respectively according to the Therminol VP1 and D12 oil type for the case with sinusoidal fin.

Image stitching and partitioning algorithms for infrared thermal human-body images

The thermal infrared image of the human body directly reflects the temperature distribution of the human body surface. Based on in-depth analysis, the infrared image can provide intelligent diagnosis assistance for human diseases. This paper proposed two preprocessing algorithms, i.e., upper-lower body image-stitching and body image partitioning, for medical infrared image analysis. In the image stitching stage, the human body is first extracted from the background by local thresholding based on the characteristics of the actual imaging environment. Then the upper and lower body images are aligned and fused using binary and grayscale template matching. In the image partitioning stage, the key points of the part area are determined by the extremum-point analysis of the human contour. The human body is then partitioned into regions including head, trunk, limbs, etc. Experiments show that the proposed preprocessing algorithms produce satisfactory results in image-stitching and portioning, and can effectively support the quantitative and qualitative analysis of human body temperature distribution.

Thermal response analysis of reinforced concrete box girder during hot-mixed asphalt mixture paving

Hot-mixed asphalt (HMA) concrete has been extensively used in the concrete box-girder bridge deck pavement due to its excellent performance and driving comfort. Nevertheless, during HMA concrete construction, the high paving temperature may disturb the thermal field of the bridge, thereby causing the significant thermal response throughout the box girder. Therefore, this research aims to investigate the temperature behavior and thermal stress of a reinforced concrete box girder segment during HMA concrete paving. The transient thermal field theory and element deletion method were first adopted to establish a three-dimensional finite element model of a reinforced concrete box girder segment and simulate the dynamic paving process, respectively. Subsequently, the bridge monitoring data was used to validate the thermal field model and then the temperature distribution analysis was conducted. Finally, the thermal stress in the bridge was studied in cross-sectional area. Results demonstrate that the vertical temperature of the concrete box-girder during the paving process is declined with the increasing vertical distance to SFRC leveling layer, and its highest value occurs at 36min after starting to paving. Furthermore, in the vertical direction, the west web-plate is subjected to compressive stress at locations of two ends and tensile stress at locations of the middle. Meanwhile, the thermal stresses undergo a decline trend after short-term growth both in the box and flange slab in the transversal direction.

Establishment of rubber thermo-viscoelastic constitutive model and analysis of temperature field

Rubber has strong nonlinear viscoelastic behavior. Under the periodically changing external forces, it show deformation hysteresis, mechanical loss and heat generation. In this work, a pair of extruding and rotating steel-rubber rollers was researched. Stress relaxation data at different temperatures were obtained through dynamic thermomechanical analysis experiments. A thermo-viscoelastic rubber constitutive model with temperature factor was obtained by combining the generalized Maxwell model where parameters of rubber viscoelastic were fitted with Prony series. Then, the temperature experiment of structure was conducted on the experimental platform. Based on thermo-viscoelastic constitutive model, simulation and analysis of temperature distribution of steel-rubber roller was obtained. The results of experimental data were consistent with simulation results. Further, the rubber constitutive models of pure elasticity, the superposition of elasticity and viscoelasticity with non-temperature factors, the superposition of elasticity and viscoelasticity with temperature factors were simulated respectively. The results show that the third model was more consistent with the actual experimental results, which verifies the accuracy of constitutive model building by this work. Through numerical comparison and analysis, it was proved that viscoelastic hysteretic heat generation is an indispensable source of heat generation in rubber structure movement.

Thermal analysis of fluidized particle flows in a finned tube solar receiver

This paper addresses experimental results on fluidized particle-in-tube solar receiver using a finned tube in order to increase wall-to-particle heat transfer. On-sun tests of a single finned tube solar receiver were performed at the focus of the 1 MW solar furnace of Odeillo. Several solar flux densities and distributions (mean values 236–485 kW/m2) and particle mass flux densities (G = 20–110 kg/m2·s) were tested. A detailed analysis of tube wall and particle temperature distributions and temperature measurement accuracy is proposed. The power extracted by the particle suspension ranges between 17.8 kW and 32 kW and the typical thermal efficiency of this lab-scale solar receiver is about 75%. The mean global wall-to-fluidized particle heat transfer coefficient is calculated as 1200 ± 400 W/m2·K for G in the range 30–110 kg/m2·s. The main uncertainty on the heat transfer coefficient is due to uncertainty on wall temperature measurement during on-sun experiments. The range of this uncertainty is estimated by comparing infra-red camera measurements and wall-welded thermocouple data.

Thermodynamic analysis and prediction of reservoir temperature distribution for steam stimulation

During steam stimulation of horizontal wells in heavy oil reservoir, it is necessary to estimate the reservoir temperature distribution, which has a huge impact on oil production and ultimate oil recovery. Most of previous models were derived based on infinite boundary condition and constant fluid velocity, which were not consistent with real situation of reservoir. In this paper, new energy balance equations combined with mobile boundary conditions were developed for increasing the accuracy of predicted results. Based on dimensionless conversion and numerical analysis, the optimum solution of equation system could be easily obtained, and its good performance in predicting temperature distribution was also validated. Moreover, thermodynamic mechanism of hot fluid, latent heat and sensible heat of steam, and their contributions to heating reservoir were also discussed to investigate the heat transfer pattern in reservoir. Finally, factors that could influence the reservoir temperature distribution were analyzed. It is found that: (a) both the heat conduction and the heat convection contribute to the heat transfer in hot liquid zone, and the heat convection predominates; (b) both the condensation front and heat front move outward with the injection of steam, but their expanding rates gradually drop with time; (c) as the radius increases, the radial fluid velocity will go down, leading the heat convection effect to be weakened and the heat conduction effect to become obvious; (d) there are some factors that can influence the reservoir temperature distribution including steam injection duration, fluid velocity, volumetric heat capacity of fluid, steam quality and thermal conductivity of reservoir.

Temperature distribution analysis on diffusion bonded joints of Ti-6Al-4V with AISI 4140 medium carbon steel

The major purpose of the present study is to investigate and compare the characteristics of dissimilar joining of Ti-6Al-4V with AISI 4140 Medium carbon steel using diffusion bonding process and analysis of the temperature distribution and stress intensity with the help of ANSYS software. For the diffusion bonding the joint quality is based on the process parameters like time, temperature and pressure maintained during the process. Diffusion bonding experiments for Ti-6Al-4V with AISI 4140 Medium carbon steel was carried out by varying the Pressure 5 MPa, 10 MPa and 15 Mpa, temperature 750 °C, 800 °C and 850 °C also time 60 min, 90 min and 120 min. The diffusion bonded joints of the Ti-6Al-4V with AISI 4140 Medium carbon steel created and temperature distribution were done by ANSYS.