Radial–Axial Transient Heat Conduction in a Region Bounded Internally by a Circular Cylinder of Finite Length and Appreciable Heat Capacity

1973 ◽  
Vol 51 (11) ◽  
pp. 1182-1186 ◽  
Author(s):  
W. T. Kierkus ◽  
N. Mani ◽  
J. E. S. Venart
Keyword(s):  
Heat Capacity ◽  
Heat Conduction ◽  
Circular Cylinder ◽  
Finite Length ◽  
Transient Heat Conduction ◽  
Zero Temperature ◽  
Transient Hot Wire ◽  
Hot Wire ◽  
Wire Method ◽  
Long Cylinder

The problem of two-dimensional transient heat conduction from a circular cylinder of finite length and appreciable heat capacity has been solved using a Laplace transformation with respect to time and a finite Fourier sine transformation with respect to the axial variable. A case of constant surface heat flux with the ends of the cylinder maintained at zero temperature is considered. The solution, valid for all values of time, is compared with that of Jaeger for the infinitely long cylinder. The results are of use in the evaluation of heat losses for the transient hot-wire method of determining the thermal conductivity of fluids.

Study on the Thermoconductivity Properties and Mechanism of Boron-Containing Slag

2010 ◽  
Vol 160-162 ◽  
pp. 1399-1404 ◽  
Author(s):  
Hong Ren Zhan ◽  
Zhan Guo Fan ◽  
Xiao Fen Jiang ◽  
Jie Li ◽  
Tao Jiang
Keyword(s):  
Heat Conduction ◽  
Transient Hot Wire ◽  
Hot Wire ◽  
Temperature Zone ◽  
Silicate System ◽  
Transient Hot Wire Method ◽  
Wire Method ◽  
Conduction Theory ◽  
Integrated Utilization ◽  
Relationship Of

. In the range of 1200°C to 1500°C, the transient hot-wire method was applied to measure the thermoconductivity of boron-containing slag, and the characteristics relationship of thermoconductivity with temperature was obtained. The thermoconductivity decreased rapidly with the elevation of temperature in the concerned temperature zone. The effect of thermoconductivity from compositions was obtained in the concerned temperature zone. The thermoconductivity increased with the increase of component of SiO2 and MgO. This is in favor of realization of quick cooling and increasing efficiencies of extraction of boron. This study not only provides an important properties parameter for the integrated utilization of boron-containing slag and helps to understand the conductivity mechanism of boron-containing slag, but also has a reference significance and practical value about the development of heat conduction theory in silicate system.

scholarly journals Apparatus for routine measurements of the thermal conductivity of ice cores

1999 ◽  
Vol 29 ◽  
pp. 151-154 ◽  
Author(s):  
Crescenzo Festa ◽  
Aristide Rossi
Keyword(s):  
Thermal Conductivity ◽  
Ice Cores ◽  
Maximum Temperature ◽  
Transient Hot Wire ◽  
Hot Wire ◽  
Standard Samples ◽  
Experimental Conditions ◽  
Heating Source ◽  
Central Segment ◽  
Wire Method

AbstractAn apparatus is described for measuring the thermal conductivity of ice by the transient hot-wire method. Thermal conductivity A, is determined by tracking the thermal pulse induced in the sample by a heating source consisting of a platinum resistor. A central segment of the same platinum heating resistor acts also as a thermal sensor. A heat pulse transferred to the ice for a period of 40s gives a maximum temperature increment of about 7-14°C. In good experimental conditions, the expected reproducibility of the measurements is within ±3%. The accuracy of the method depends on whether the instrument has been calibrated by reliable standard samples, certified by absolute methods.

Clathrate and other solid phases in the tetrahydrofuran–water system: thermal conductivity and heat capacity under pressure

1982 ◽  
Vol 60 (7) ◽  
pp. 881-892 ◽  
Author(s):  
Russell G. Ross ◽  
Per Andersson
Keyword(s):  
Thermal Conductivity ◽  
Heat Capacity ◽  
Water System ◽  
Clathrate Hydrate ◽  
Transient Hot Wire ◽  
Guest Molecules ◽  
Hydrate Phase ◽  
Wire Method ◽  
Solid Phases ◽  
Thermal Conductivity Λ

Solid phases in the tetrahydrofuran–water (THF–H2O) system were investigated in the temperature range 100–260 K and at pressures up to 1.5 GPa. Thermal conductivity, λ, and heat capacity per unit volume, ρcp, were measured, using the transient hot-wire method. We made measurements on solid phases having nominal compositions THF•17H2O, THF•7•1H2O, and THF•4•6H2O, which we refer to as phases α, β, and γ, respectively. Phase α is known to be a structure II clathrate hydrate, and λ for this phase was found to be similar to other crystalline solids which are glass-like in relation to their thermal properties. Low-energy excitations are known to be relevant to the properties of glass-like solids, and, in the case of phase α, were probably rotational vibrations of the THF guest molecules. Phase β was similar, and we inferred that it was probably a structure I clathrate hydrate. Phase γ behaved nearly like a normal crystal phase at low temperatures, but λ became almost independent of temperature near melting. At 1.1 GPa and 130 K, we found evidence that phase α transformed, on pressurization, to a metastable modification which may be a new high-density form of clathrate hydrate. The astrophysical implications of our results were mentioned briefly.

scholarly journals Application and testing of a new simple experimental set-up for thermal conductivity measurements of liquids

2017 ◽  
Vol 21 (3) ◽  
pp. 1195-1202 ◽  
Author(s):  
Andrej Stanimirovic ◽  
Emila Zivkovic ◽  
Nenad Milosevic ◽  
Mirjana Kijevcanin
Keyword(s):  
Thermal Conductivity ◽  
Measurement Uncertainty ◽  
Thermophysical Properties ◽  
Deionized Water ◽  
Conductivity Measurements ◽  
Transient Hot Wire ◽  
Hot Wire ◽  
New Apparatus ◽  
Wire Method ◽  
Set Up

Transient hot wire method is considered a reliable and precise technique for measuring the thermal conductivity of liquids. The present paper describes a new transient hot wire experimental set-up and its initial testing. The new apparatus was tested by performing thermal conductivity measurements on substances whose reference thermophysical properties data existed in literature, namely on pure toluene and double distilled deionized water. The values of thermal conductivity measured in the temperature range 25 to 45 ?C deviated +2.2% to +3% from the literature data, while the expanded measurement uncertainty was estimated to be ?4%.

Analysis of the Transient Hot-Wire Method to Measure Thermal Conductivity of Silica Aerogel: Influence of Wire Length, and Radiation Properties

2014 ◽  
Vol 136 (4) ◽  
Author(s):  
Ellann Cohen ◽  
Leon Glicksman
Keyword(s):  
Thermal Conductivity ◽  
Silica Aerogel ◽  
Test Method ◽  
Wire Radius ◽  
Wire Length ◽  
Transient Hot Wire ◽  
Hot Wire ◽  
End Effects ◽  
Transient Hot Wire Method ◽  
Wire Method

When the transient hot-wire method is used to measure the thermal conductivity of very low thermal conductivity silica aerogel (in the range of 10 mW/m·K at 1 atm) end effects due to the finite wire size and radiation corrections must be considered. An approximate method is presented to account for end effects with realistic boundary conditions. The method was applied to small experimental samples of the aerogel using different wire lengths. Initial conductivity results varied with wire length. This variation was eliminated by the use of the end effect correction. The test method was validated with the NIST (National Institute of Standards and Technology) Standard Reference Material 1459, fumed silica board to within 1 mW/m·K. The aerogel is semitransparent. Due to the small wire radius and short transient, radiation heat transfer may not be fully accounted for. In a full size aerogel panel radiation will augment the phonon conduction by a larger amount.

Effect of Insulation Coating on Start Time of Linear Region for Transient Hot-wire Method

2013 ◽  
Vol 37 (12) ◽  
pp. 1147-1152
Author(s):  
Seung-Hyun Lee ◽  
Hyun Jin Kim ◽  
Kyu Han Kim ◽  
Yong-Jun Park ◽  
Seok Pil Jang
Keyword(s):  
Transient Hot Wire ◽  
Hot Wire ◽  
Start Time ◽  
Linear Region ◽  
Transient Hot Wire Method ◽  
Insulation Coating ◽  
Wire Method
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