TEMPERATURE DISTRIBUTION OF FIRE GAS FLOW FROM A BELT-SHAPED HEAT SOURCE UNDER STRONG WIND : Study on temperature distribution of big fire in urban area under strong wind

The thermal problem of functionally graded materials (FGM) under linear heat source is studied by a hybrid numerical method. The accuracy of the analytical method and the efficiency of the finite element method are taken into account. The volume fraction of FGM in the thickness direction can be changed by changing the gradient parameters. Based on the weighted residual method, the heat conduction equation under the third boundary condition is established. The temperature distribution of FGM under the action of linear heat source is obtained by Fourier transform. The results show that the closer to the heat source it is, the greater the influence of the heat source is and the influence of the heat source is local. The temperature change trend of the observation points is consistent with the heat source, showing a linear change. The results also show that the higher the value of gradient parameter is, the higher the temperature of location point is. The temperature distribution of observation points is positively correlated with gradient parameter. When the gradient parameter value exceeds a certain value, it has a little effect on the temperature change in the model and the heat conduction in the model tends to be pure metal heat conduction, the optimal gradient parameters combined the thermal insulation property of ceramics and the high strength toughness of metals are obtained.

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A Simplified Numerical Approach for Finding the Temperature Distribution in Submerged arc Welding Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.622-623.315 ◽

2012 ◽

Vol 622-623 ◽

pp. 315-318

Author(s):

Aparesh Datta ◽

Subodh Debbarma ◽

Subhash Chandra Saha

Keyword(s):

Temperature Distribution ◽

Heat Source ◽

Arc Welding ◽

Welding Process ◽

Numerical Approach ◽

High Heat ◽

Submerged Arc Welding ◽

Fusion Welding ◽

Arc Welding Process ◽

Submerged Arc

The quality of joining has assumed a greater role in fabrication of metal in recent years, because of the development of new alloys with tremendously increased strength and toughness. Submerged arc welding is a high heat input fusion welding process in which weld is produced by moving localized heat source along the joint. The weld quality in turn affected by thermal cycle that the weldment experiences during the welding. In the present study a simple comprehensive mathematical model has been developed using a moving heat source and analyzing the temperature on one section and then the temperature distribution of other section are correlated with time delay with reference analyzed section.

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Study on Effective Radial Thermal Conductivity of Gas Flow through a Methanol Reactor

International Journal of Chemical Reactor Engineering ◽

10.1515/ijcre-2014-0065 ◽

2015 ◽

Vol 13 (1) ◽

pp. 103-112 ◽

Cited By ~ 1

Author(s):

Kun Lei ◽

Hongfang Ma ◽

Haitao Zhang ◽

Weiyong Ying ◽

Dingye Fang

Keyword(s):

Heat Transfer ◽

Thermal Conductivity ◽

Reynolds Number ◽

Temperature Distribution ◽

Large Scale ◽

Gas Flow ◽

Fixed Bed ◽

Heat Transfer Model ◽

Transfer Model ◽

Particle Reynolds Number

Abstract The heat conduction performance of the methanol synthesis reactor is significant for the development of large-scale methanol production. The present work has measured the temperature distribution in the fixed bed at air volumetric flow rate 2.4–7 m3 · h−1, inlet air temperature 160–200°C and heating tube temperature 210–270°C. The effective radial thermal conductivity and effective wall heat transfer coefficient were derived based on the steady-state measurements and the two-dimensional heat transfer model. A correlation was proposed based on the experimental data, which related well the Nusselt number and the effective radial thermal conductivity to the particle Reynolds number ranging from 59.2 to 175.8. The heat transfer model combined with the correlation was used to calculate the temperature profiles. A comparison with the predicated temperature and the measurements was illustrated and the results showed that the predication agreed very well with the experimental results. All the absolute values of the relative errors were less than 10%, and the model was veriﬁed by experiments. Comparing the correlations of both this work with previously published showed that there are considerable discrepancies among them due to different experimental conditions. The influence of the particle Reynolds number on the temperature distribution inside the bed was also discussed and it was shown that improving particle Reynolds number contributed to enhance heat transfer in the fixed bed.

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Catalytic Micro Gas Sensor with Excellent Homogeneous Temperature Distribution and Low Power Consumption for Long-Term Stable Operation

Proceedings ◽

10.3390/proceedings2130927 ◽

2018 ◽

Vol 2 (13) ◽

pp. 927 ◽

Cited By ~ 1

Author(s):

Anmona Shabnam Pranti ◽

Daniel Loof ◽

Sebastian Kunz ◽

Marcus Bäumer ◽

Walter Lang

Keyword(s):

Temperature Distribution ◽

Low Power ◽

Gas Sensor ◽

Gas Flow ◽

Pt Nanoparticles ◽

Stable Operation ◽

Catalytic Layer ◽

Micro Gas Sensor ◽

Homogeneous Temperature

This paper presents a long-term stable thermoelectric micro gas sensor with ligand linked Pt nanoparticles as catalyst. The sensor design gives an excellent homogeneous temperature distribution over the catalytic layer, an important factor for long-term stability. The sensor consumes very low power, 18 mW at 100 °C heater temperature. Another thermoresistive sensor is also fabricated with same material for comparative analysis. The thermoelectric sensor gives better temperature homogeneity and consumes 23% less power than thermoresistive sensor for same average temperature on the membrane. The sensor shows linear characteristics with temperature change and has significantly high Seebeck coefficient of 6.5 mV/K. The output of the sensor remains completely constant under 15,000 ppm continuous H2 gas flow for 24 h. No degradation of sensor signal for 24 h indicates no deactivation of catalytic layer over the time. The sensor is tested with 3 different amount of catalyst at 2 different operating temperatures under 6000 ppm and 15,000 ppm continuous H2 gas flow for 4 h. Sensor output is completely stable for 3 different amount of catalyst.

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Plane Strain Deformation In A Thermoelastic Microelongated Solid With Internal Heat Source

International Journal of Applied Mechanics and Engineering ◽

10.1515/ijame-2015-0047 ◽

2015 ◽

Vol 20 (4) ◽

pp. 717-731

Author(s):

P. Ailawalia ◽

S.K. Sachdeva ◽

D.S. Pathania

Keyword(s):

Temperature Distribution ◽

Heat Source ◽

Normal Mode Analysis ◽

Internal Heat ◽

Internal Heat Source ◽

Displacement Component ◽

Mode Analysis ◽

Plane Strain Deformation ◽

Gl Theory ◽

Component Force

Abstract The purpose of this paper is to study the two dimensional deformation due to an internal heat source in a thermoelastic microelongated solid. A mechanical force is applied along an overlaying elastic layer of thickness h. The normal mode analysis has been applied to obtain the exact expressions for the displacement component, force stress, temperature distribution and microelongation. The effect of the internal heat source on the displacement component, force stress, temperature distribution and microelongation has been depicted graphically for Green-Lindsay (GL) theory of thermoelasticity.

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Analysis of the Effect of Anode Porosity on Temperature Distribution on Planar Radial Type SOFC

E3S Web of Conferences ◽

10.1051/e3sconf/20187301010 ◽

2018 ◽

Vol 73 ◽

pp. 01010

Author(s):

Alif Widiyanto ◽

Sulistyo ◽

MSK Tony Suryo Utomo

Keyword(s):

Temperature Distribution ◽

Gas Flow ◽

Hydrogen Gas ◽

Cfd Modeling ◽

Dynamics Modeling ◽

Waste Products ◽

Geometry Model ◽

Electrolyte Surface ◽

Fluent Software ◽

Object Of Study

Solid Oxide Fuel Cell (SOFC) is an electrochemical equipment that converts gas into electricity directly. The waste products resulting from SOFC are water vapor and heat when using hydrogen gas. The electrode of the SOFC is the anode, electrolyte and cathode. The performance of SOFC is influenced porosity of the electrode. This study explained the relationship between porosity of the anode and temperature distribution using computational fluid dynamics modeling approach (CFD). In this study, CFD modeling was done by using Fluent software. The geometry model of computational modeling is a planar radial-type SOFC. The assumptions of some boundary conditions used from the study of literature and the object of study. The standard deviation and the different of temperature of the anode-electrolyte surface used to analyse the result. Non-homogenous temperature distribution rise if the anode porosity and gas flow rate is increasing. This indicates the gradient of temperature is bigger in the higher porosity, which may cause thermal stress and degrades the materials of electrode.

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