Optimization and solution of the temperature curve of the furnace

Multicanonical molecular dynamics simulations are applied, for the first time, to study the liquid-solid and solid-solid transitions in Lennard-Jones (LJ) clusters. The transition temperatures are estimated based on the peak position in the heat capacity versus temperature curve. For LJ31, LJ58 and LJ98, our results on the solid-solid transition temperature are in good agreement with previous ones. For LJ309, the predicted liquid-solid transition temperature is also in agreement with previous result.

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Theoretical Effect of Temperature on Threshold in the Hodgkin-Huxley Nerve Model

The Journal of General Physiology ◽

10.1085/jgp.49.5.989 ◽

1966 ◽

Vol 49 (5) ◽

pp. 989-1005 ◽

Cited By ~ 39

Author(s):

Richard Fitzhugh

Keyword(s):

Relaxation Time ◽

Relaxation Times ◽

Giant Axon ◽

Temperature Curve ◽

Effect Of Temperature ◽

Threshold Temperature ◽

Ionic Conductances ◽

And Shifts ◽

The Right ◽

Increasing Temperature

In the squid giant axon, Sjodin and Mullins (1958), using 1 msec duration pulses, found a decrease of threshold with increasing temperature, while Guttman (1962), using 100 msec pulses, found an increase. Both results are qualitatively predicted by the Hodgkin-Huxley model. The threshold vs. temperature curve varies so much with the assumptions made regarding the temperature-dependence of the membrane ionic conductances that quantitative comparison between theory and experiment is not yet possible. For very short pulses, increasing temperature has two effects. (1) At lower temperatures the decrease of relaxation time of Na activation (m) relative to the electrical (RC) relaxation time favors excitation and decreases threshold. (2) For higher temperatures, effect (1) saturates, but the decreasing relaxation times of Na inactivation (h) and K activation (n) factor accommodation and increased threshold. The result is a U-shaped threshold temperature curve. R. Guttman has obtained such U-shaped curves for 50 µsec pulses. Assuming higher ionic conductances decreases the electrical relaxation time and shifts the curve to the right along the temperature axis. Making the conductances increase with temperature flattens the curve. Using very long pulses favors effect (2) over (1) and makes threshold increase monotonically with temperature.

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Optimization Model Design for Temperature Curve of Reflow Furnace

Journal of Physics Conference Series ◽

10.1088/1742-6596/1802/2/022020 ◽

2021 ◽

Vol 1802 (2) ◽

pp. 022020

Author(s):

Xindi Luo ◽

Zeshu Wang ◽

Wenhao Deng

Keyword(s):

Optimization Model ◽

Temperature Curve ◽

Model Design

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Finite Element Study of Container Structure under Normal and High Temperature

Mathematical Problems in Engineering ◽

10.1155/2016/2652149 ◽

2016 ◽

Vol 2016 ◽

pp. 1-15 ◽

Cited By ~ 5

Author(s):

Xiaoxiong Zha ◽

Yang Zuo

Keyword(s):

Finite Element ◽

High Temperature ◽

Research Result ◽

Temperature Curve ◽

Temperature Fields ◽

Wind Loading ◽

Coupled Analysis ◽

Fire Dynamics ◽

Standard Temperature ◽

Actual Temperature

This paper does some research on the mechanical property of multilayer container structure under high temperature and gives some suggestions on how to make fire protection based on the performance-based fire design. Firstly, using the software of FDS (Fire Dynamics Simulator), the fire background and fire heating release curve are determined. Through the simulation, the actual temperature curves (of the top and bottom temperature curves of the middle, door, and corner position in the container) are obtained and compared with the standard temperature curve of ISO-834. Secondly, using the software of Abaqus, a full scale finite element model of multilayer container structure is established. Two temperature fields under the standard temperature curve of ISO-834 and the actual temperature curve (of the most unfavorable curve of the top temperature curve of the middle position in the container) are obtained, respectively. Thirdly, the thermal-mechanical coupled analysis is carried out for the container structure under the wind loading and temperature field. The research result can be feasible in design and construction of container buildings and provides some references to corresponding specification preparation.

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Tensile Properties of Low Nickel Austenitic Stainless Steel at Elevated Temperatures

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.159.346 ◽

2012 ◽

Vol 159 ◽

pp. 346-350

Author(s):

Shu Min Liu ◽

Jian Bin Zhang

Keyword(s):

Tensile Strength ◽

Stainless Steel ◽

Elevated Temperatures ◽

Peak Stress ◽

Temperature Curve ◽

Delta Ferrite ◽

Cross Sectional ◽

Different Temperatures ◽

Increasing Temperature ◽

Reduction Percentage

The elevated temperature short-time tensile test with the sample of casting low nickel stainless steel was conducted on SHIMADZU AG-10 at ten temperatures 300, 500, 600, 700, 800, 950, 1000, 1050, 1100, and 1250°C, respectively. The stress-strain curves with the thermal deformation at the different temperatures, the peak stress intensity-temperature curve, and the reduction percentage of cross sectional area-temperature curve were obtained. Metallographic test samples were prepared and the morphology of deforming zone was observed by optical microscopy. The experimental results show that the tensile strength of the test samples decreases with increasing temperature. From 300 to 800°C, the work harding occurred and the tensile strength increases with increasing strain. The work softening occurred and the tensile strength decreases with increasing strain at temperatures of 800 to 1250°C. The minimum value of reduction percentage was measured at 800 °C. The austenite and delta-ferrite are the main phase in the tested samples. When the tensile temperatures are increased to 1200°C, the delta-ferrite became thinner and broke down to be spheroidized.

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Effect of Sintering Temperature and Time in Nickel Wick for Loop Heat Pipe with Flat Evaporator

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.602-605.528 ◽

2014 ◽

Vol 602-605 ◽

pp. 528-532

Author(s):

Shen Chun Wu ◽

Chang Yu Wu ◽

Weie Jhih Lin ◽

Jia Ruei Chen ◽

Yau Ming Chen

Keyword(s):

Heat Pipe ◽

Constant Temperature ◽

Heat Load ◽

Sintering Temperature ◽

Performance Testing ◽

Effective Porosity ◽

Temperature Curve ◽

Loop Heat Pipe ◽

Maximum Heat ◽

Load Increase

This paper specifically addresses the effect of changing the constant temperature region of the sintering temperature curve in manufacturing nickel powder capillary structure (wick) on the performance of a flat loop heat pipe (FLHP). The sintering temperature curve is composed of three regions: a region of increasing temperature, a region of constant temperature, and a region of decreasing temperature, with the sintering time and temperature in the region of constant temperature having significant effect on the permeability of the wick. In this study, for wick manufacturing the temperatures in this region tested range from 550°C to 650°C and the time from 30 minutes to 60 minutes. The properties and internal parameters of the wick are measured, and the wick is placed into FLHP for performance testing. Experimental results show that at sintering temperature of 550°C and lasting about 45 minutes, maximum heat load is 200W, minimum thermal resistance is 0.32°C/W, permeability is , porosity is 66%, effective porosity is 3.8and heat flux is around 21W/cm2; related literatures have only reported maximum heat load increase of 25%.

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