scholarly journals Fea-Based Structural Heat Transfer Characteristic of 3-D Orthogonal Woven Composite Subjected to the Non-Uniform Heat Load

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Qian Ma ◽  
Ke Wang ◽  
Shudong Wang ◽  
Hongtao Zhou ◽  
Limin Jin ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Temperature Distribution ◽  
Heat Load ◽  
Transfer Characteristic ◽  
Resin Matrix ◽  
Distribution Characteristics ◽  
Woven Composite ◽  
Element Analysis ◽  
Fabric Reinforcement ◽  
Uniform Heat

Abstract The thermodynamic behavior of 3-D orthogonal woven composite is studied to explore its structural heat transfer mechanism in a non-uniform heat load field based on finite element analysis (FEA). The temperature distribution characteristics of the resin matrix and the fabric reinforcement are observed to compare the heat absorption. Furthermore, the dynamic expansion and distribution characteristics of temperature in the 3-D orthogonal woven composite structure have also been quantitatively studied, together with simultaneously obtaining the path characteristics of the heat transfer in each system (i.e., warp yarns, weft yarns, and Z-yarns). In addition, the spatial temperature distribution characteristics of each yarn system in the fabric reinforcement are also explored. Thus, the structural mechanism of heat conduction for 3-D orthogonal woven composite is obtained.

scholarly journals Surface Temperature Distribution Characteristics of Marangoni Condensation for Ethanol–Water Mixture Vapor Based on Thermal Infrared Images

Energies ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 6057
Author(s):  
Guilong Zhang ◽  
Ziqiang Ma ◽  
Heng Li ◽  
Jinshi Wang
Keyword(s):  
Heat Transfer ◽  
Temperature Distribution ◽  
Surface Temperature ◽  
Thermal Infrared ◽  
Water Mixture ◽  
Distribution Characteristics ◽  
Infrared Images ◽  
Single Droplet ◽  
Surface Temperature Distribution ◽  
Thermal Infrared Images

Marangoni condensation is formed due to the surface tension gradient caused by the local temperature or concentration gradient on the condensate surface; thus, the investigation of the surface temperature distribution characteristics is crucial to reveal the condensation mechanism and heat transfer characteristics. Few studies have been conducted on the temperature distribution of the condensate surface. In this study, thermal infrared images were used to measure the temperature distributions of the condensate surface during Marangoni condensation for ethanol–water mixture vapor. The results showed that the surface temperature distribution of the single droplet was uneven, and a large temperature gradient, approximately 15.6 °C/mm, existed at the edge of the condensate droplets. The maximum temperature difference on the droplet surface reached up to 8 °C. During the condensation process, the average surface temperature of a single droplet firstly increased rapidly and then slowly until it approached a certain temperature, whereas that of the condensate surface increased rapidly at the beginning and then changed periodically in a cosine-like curve. The present results will be used to obtain local heat flux and heat transfer coefficients on the condensing surface, and to further establish the relationship between heat transfer and temperature distribution characteristics.

Thermal-Electric Finite Element Analysis and Experimental Validation of Bipolar Electrosurgical Cautery

2008 ◽  
Vol 130 (2) ◽  
Author(s):  
Robert E. Dodde ◽  
Scott F. Miller ◽  
James D. Geiger ◽  
Albert J. Shih
Keyword(s):  
Heat Transfer ◽  
Electrical Conductivity ◽  
Finite Element ◽  
Temperature Distribution ◽  
Tissue Temperature ◽  
Temperature Dependent ◽  
Element Analysis ◽  
Temperature Dependent Thermal Conductivity ◽  
Insight Into ◽  
Good Agreement

Cautery is a process to coagulate tissues and seal blood vessels using heat. In this study, finite element modeling (FEM) was performed to analyze temperature distribution in biological tissue subject to a bipolar electrosurgical technique. FEM can provide detailed insight into the tissue heat transfer to reduce the collateral thermal damage and improve the safety of cautery surgical procedures. A coupled thermal-electric FEM module was applied with temperature-dependent electrical and thermal properties for the tissue. Tissue temperature was measured using microthermistors at different locations during the electrosurgical experiments and compared to FEM results with good agreement. The temperature- and compression-dependent electrical conductivity has a significant effect on temperature profiles. In comparison, the temperature-dependent thermal conductivity does not impact heat transfer as much as the temperature-dependent electrical conductivity. Detailed results of temperature distribution were obtained from the model. The FEM results show that the temperature distribution can be changed with different electrode geometries. A flat electrode was modeled that focuses the current density at the midline of the instrument profile resulting in higher peak temperature than that of the grooved electrode (105 versus 96°C).

scholarly journals Effect of Ambient Parameters on the Temperature Distribution of Photovoltaic (PV) Modules

Resources ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 107 ◽  
Author(s):  
Divine Atsu ◽  
Alok Dhaundiyal
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Temperature Distribution ◽  
Transfer Coefficient ◽  
Thermal Conditions ◽  
Main Body ◽  
Pv System ◽  
Element Analysis ◽  
Pv Modules ◽  
The Heat Transfer Coefficient

This paper pivots around the influence of thermal parameters on the temperature distribution of a (PV) module. The solar irradiance, ambient temperature, and heat transfer coefficient were examined for four differently manufactured solar modules. A finite element analysis of the solar system was carried out to simulate the prevailing thermal conditions. It was determined through analysis that the heat transfer coefficient had a significant effect on the boundaries of the PV modules. The temperature gradient was relatively high at the boundary, whereas the main body had the least deviation from the mean value of experimental data. The high value of irradiance is favorable for a large PV system, while the heat transfer coefficient should be low for avoiding undulation of the thermal gradient across the plate. The temperature distribution on the surface of the PV modules largely depended on the geometry and the material used for the design purpose.

scholarly journals Research on Impact of Cooling Fan’s Geometry on Nozzle’s Heat Load of the Air-Cooled Diesel Engine

2015 ◽  
Vol 9 (1) ◽  
pp. 99-105
Author(s):  
Jun Fu ◽  
Yuan Tang ◽  
Wenhua Yuan ◽  
Guangming Li ◽  
Wei Chen ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Temperature Distribution ◽  
Heat Load ◽  
Needle Valve ◽  
Good Effect ◽  
Cooling Fan ◽  
Installation Angle ◽  
Test Points ◽  
Fan Blade ◽  
The Impact

In order to study the nozzle’s temperature distribution and to reduce its heat load, the heat transfer boundary condition of nozzle has been simplified appropriately, considering the details of the convectional heat transfer inside the nozzle and the needle body contact heat transfer. Results of the simulation with ANSYS software show that the nozzle’s temperature distribution is complicated and high-temperature region are concentrated in the nozzle’s head. Considering the fact that the cooling fan plays an important role in reducing the heat load of air-cooled engine, the test points were reasonably selected to measure the needle valve body’s temperature as well as to seek reasonable cooling fan blade numbers and the blade installation angle for the air outlet in order to improve the thermal load of the nozzle. It was found that the nozzle’s temperature decreases at first but then increased when the fan blade numbers and the blade installation angle for air outlet increased, and the impact of the number of blades on the nozzle’s temperature was more significant than the blade installation angle for the air outlet. With the scheme of the blade installation angle of 132° with respect to the air outlet and with 20 blades, the temperature of the nozzle needle valve’s head and middle decreases to 21 K and 7 K on average compared with the original scheme, which has a good effect on reducing the temperature of the nozzle’s needle valve head, and the temperature gradient between two test points also reduced by 0.65 K/mm on average. It provides a reference for reducing the nozzle’s heat load.

scholarly journals Study on Thermoelectric Conversion and Conjugate Heat Transfer for PCBA by Finite Element Analysis

2019 ◽  
Vol 10 (1) ◽  
pp. 197
Author(s):  
Ah-Der Lin ◽  
Sian Zheng Poon ◽  
Hong-Wei Tu ◽  
Cheng-Yi Chen ◽  
Chao-Ming Hsu
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Finite Element Analysis ◽  
Finite Element ◽  
Temperature Distribution ◽  
High Power ◽  
Conjugate Heat Transfer ◽  
Element Analysis ◽  
The Finite Element Analysis ◽  
High Power Led

In this study, the optical sphere and the power analyzer were exploited to measure the optical and power parameters for the high-power LED lamps. The results, derived from the experimental data, were used as the power distribution inputs in the finite element analysis (FEA) for the determination of the temperature distribution for the printed circuit board assembly (PCBA) built in the LED lamp. In the finite element analysis, the conjugate heat transfer model was adapted for the calculation of the heat transfer, including thermal conductivity, convection and radiation. Applied on the power chips located on the PCBA, the graphene thermal interface material (TIMs) had been studied for its effects on the temperature distribution. For an accurate simulation about the LED lamp, the model with closed and compact space was built in the analysis. Compared to the experimental data, it showed that the simulation results had a deviation in the range of 3–5% around the main heating source, the light-emitting diodes. It proves the FEA model proposed in this study were well developed for the simulation of the temperature distribution for the high-power LED lamps which have mixed heat transfer mechanisms. The thermal radiation effects by TIMs with graphene were also investigated in this study and proven to be useful for the heat dissipation for the LED lamps.

Lifetime Prediction of Tires with Regard to Oxidative Aging5

2008 ◽  
Vol 36 (1) ◽  
pp. 63-79 ◽  
Author(s):  
L. Nasdala ◽  
Y. Wei ◽  
H. Rothert ◽  
M. Kaliske
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Temperature Distribution ◽  
Superposition Principle ◽  
Accelerated Aging ◽  
Material Model ◽  
Aging Behavior ◽  
Element Analysis ◽  
Material Parameters ◽  
Reaction Processes

Abstract It is a challenging task in the design of automobile tires to predict lifetime and performance on the basis of numerical simulations. Several factors have to be taken into account to correctly estimate the aging behavior. This paper focuses on oxygen reaction processes which, apart from mechanical and thermal aspects, effect the tire durability. The material parameters needed to describe the temperature-dependent oxygen diffusion and reaction processes are derived by means of the time–temperature–superposition principle from modulus profiling tests. These experiments are designed to examine the diffusion-limited oxidation (DLO) effect which occurs when accelerated aging tests are performed. For the cord-reinforced rubber composites, homogenization techniques are adopted to obtain effective material parameters (diffusivities and reaction constants). The selection and arrangement of rubber components influence the temperature distribution and the oxygen penetration depth which impact tire durability. The goal of this paper is to establish a finite element analysis based criterion to predict lifetime with respect to oxidative aging. The finite element analysis is carried out in three stages. First the heat generation rate distribution is calculated using a viscoelastic material model. Then the temperature distribution can be determined. In the third step we evaluate the oxygen distribution or rather the oxygen consumption rate, which is a measure for the tire lifetime. Thus, the aging behavior of different kinds of tires can be compared. Numerical examples show how diffusivities, reaction coefficients, and temperature influence the durability of different tire parts. It is found that due to the DLO effect, some interior parts may age slower even if the temperature is increased.

Sign in / Sign up

Export Citation Format

Share Document