Heat Capacity, Conductivity, and the Thermal Coefficient of Expansion

The problem of dephosphorization of iron-carbon alloys is relevant for the metallurgical industry, since a high concentration of phosphorus contributes to the appearance of a number of extremely undesirable phenomena. A lot of experimental work has been devoted to solving this problem, but it has still not been completely possible to cope with it. Any field experiments aimed at studying the process of phosphorus removal, require considerable material and time costs, but at the same time do not guarantee getting the desired result. Therefore, to search for new approaches to solving this problem, it is much more rational to use numerical simulation methods involving the computational capabilities of modern computers. At present, computer experiments are the same recognized research method as theoretical research and real experiment. To study the behavior of phosphorus atoms in iron using a numerical experiment, it is necessary to build a computational model and test it by calculating various characteristics whose values are known in advance. In this paper, the method of molecular dynamics was chosen as the method of computer simulation. Using this method, one can conduct experiments with given atomic velocities and describe dynamics of the studied processes. To describe the interparticle interaction, we used the potential calculated in the framework of the immersed atom method. The study was conducted on a computational cell simulating α-iron crystal with phosphorus substitution atoms. The constructed model demonstrated satisfactory results when calculating the known characteristics of the simulated system. Dependences of changes in such characteristics as temperature coefficient of linear expansion, melting point, latent heat of melting and heat capacity on the concentration of phosphorus atoms, as well as in some cases on magnitude of the applied external pressure were established. Calculations showed that, for example, the phosphorus concentration of 0.5 % leads to an increase in the average thermal coefficient of linear expansion by 9 %, a decrease in temperature and latent heat of fusion by 5 % and a heat capacity by 7 %.

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HEAT CAPACITY MEASUREMENTS ON THE DILUTED ISING SYSTEM Cs3CopZn1-pCl5

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19711359 ◽

1971 ◽

Vol 32 (C1) ◽

pp. C1-1008-C1-1009 ◽

Cited By ~ 3

Author(s):

E. LAGENDIJK ◽

W. J. HUISKAMP ◽

P. F. BONGERS

Keyword(s):

Heat Capacity ◽

Ising System ◽

Heat Capacity Measurements

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HEAT CAPACITY OF NEODYMIUM BELOW 10 K

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19786354 ◽

1978 ◽

Vol 39 (C6) ◽

pp. C6-794-C6-795 ◽

Cited By ~ 1

Author(s):

E. M. Forgan ◽

C. M. Muirhead

Keyword(s):

Heat Capacity

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TEMPERATURE-LINEAR TERM OF HEAT CAPACITY OF La-Ba-Cu-O AND La-Sr-Cu-O SYSTEMS

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19888954 ◽

1988 ◽

Vol 49 (C8) ◽

pp. C8-2133-C8-2134

Author(s):

K. Kumagai ◽

Y. Nakamura ◽

I. Watanabe ◽

Y. Nakamichi ◽

H. Nakajima

Keyword(s):

Heat Capacity ◽

Linear Term

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THE MECHANISM OF RAISING AND QUANTIFICATION OF SPECIFIC HEAT FLUX AT BOILING OF NANOFLUIDS IN FREE CONVECTION CONDITIONS

Energy Technologies & Resource Saving ◽

10.33070/etars.3.2017.03 ◽

2017 ◽

pp. 25-34

Author(s):

V.N. Moraru

Keyword(s):

Heat Transfer ◽

Heat Flux ◽

Heat Capacity ◽

Specific Heat ◽

Chemical Properties ◽

Heating Surface ◽

Physical Models ◽

Superheated Liquid ◽

Two Phase ◽

Boiling Process

The results of our work and a number of foreign studies indicate that the sharp increase in the heat transfer parameters (specific heat flux q and heat transfer coefficient _) at the boiling of nanofluids as compared to the base liquid (water) is due not only and not so much to the increase of the thermal conductivity of the nanofluids, but an intensification of the boiling process caused by a change in the state of the heating surface, its topological and chemical properties (porosity, roughness, wettability). The latter leads to a change in the internal characteristics of the boiling process and the average temperature of the superheated liquid layer. This circumstance makes it possible, on the basis of physical models of the liquids boiling and taking into account the parameters of the surface state (temperature, pressure) and properties of the coolant (the density and heat capacity of the liquid, the specific heat of vaporization and the heat capacity of the vapor), and also the internal characteristics of the boiling of liquids, to calculate the value of specific heat flux q. In this paper, the difference in the mechanisms of heat transfer during the boiling of single-phase (water) and two-phase nanofluids has been studied and a quantitative estimate of the q values for the boiling of the nanofluid is carried out based on the internal characteristics of the boiling process. The satisfactory agreement of the calculated values with the experimental data is a confirmation that the key factor in the growth of the heat transfer intensity at the boiling of nanofluids is indeed a change in the nature and microrelief of the heating surface. Bibl. 20, Fig. 9, Tab. 2.

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ABOUT HEAT CAPACITY OF TITANIUM CARBIDE TiCx

Alternative Energy and Ecology (ISJAEE) ◽

10.15518/isjaee.2019.01-03.056-066 ◽

2019 ◽

pp. 56-66

Author(s):

I. Khidirov ◽

V. V. Getmanskiy ◽

A. S. Parpiev ◽

Sh. A. Makhmudov

Keyword(s):

Heat Capacity ◽

High Temperature ◽

Titanium Carbide ◽

Temperature Dependence ◽

Carbon Concentration ◽

Room Temperature ◽

Thermodynamic Characteristics ◽

Liquid Nitrogen Temperature ◽

Analysis Data ◽

Thermal Excitation

This work relates to the field of thermophysical parameters of refractory interstitial alloys. The isochoric heat capacity of cubic titanium carbide TiCx has been calculated within the Debye approximation in the carbon concentration range x = 0.70–0.97 at room temperature (300 K) and at liquid nitrogen temperature (80 K) through the Debye temperature established on the basis of neutron diffraction analysis data. It has been found out that at room temperature with decrease of carbon concentration the heat capacity significantly increases from 29.40 J/mol·K to 34.20 J/mol·K, and at T = 80 K – from 3.08 J/mol·K to 8.20 J/mol·K. The work analyzes the literature data and gives the results of the evaluation of the high-temperature dependence of the heat capacity СV of the cubic titanium carbide TiC0.97 based on the data of neutron structural analysis. It has been proposed to amend in the Neumann–Kopp formula to describe the high-temperature dependence of the titanium carbide heat capacity. After the amendment, the Neumann–Kopp formula describes the results of well-known experiments on the high-temperature dependence of the heat capacity of the titanium carbide TiCx. The proposed formula takes into account the degree of thermal excitation (a quantized number) that increases in steps with increasing temperature.The results allow us to predict the thermodynamic characteristics of titanium carbide in the temperature range of 300–3000 K and can be useful for materials scientists.

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Heat capacity by the radiant energy absorption technique

10.2514/6.1967-303 ◽

1967 ◽

Cited By ~ 2

Author(s):

O. MAKAROUNIS

Keyword(s):

Heat Capacity ◽

Energy Absorption ◽

Radiant Energy ◽

Absorption Technique

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Ideal–Gas Thermochemical Properties for Alkanolamine and Related Species Involved in Carbon Capture Applications

10.26434/chemrxiv.12743552 ◽

2020 ◽

Author(s):

Nayyereh hatefi ◽

William Smith

Keyword(s):

Heat Capacity ◽

Electronic Structure ◽

Co2 Capture ◽

Carbon Capture ◽

Ideal Gas ◽

Thermochemical Properties ◽

Temperature Range ◽

Comparison Results ◽

Electronic Structure Methods ◽

Protonated Forms

<div>Ideal{gas thermochemical properties (enthalpy, entropy, Gibbs energy, and heat capacity, Cp) of 49 alkanolamines potentially suitable for CO2 capture applications and their carbamate and protonated forms were calculated using two high{order electronic structure methods, G4 and G3B3 (or G3//B3LYP). We also calculate for comparison results from the commonly used B3LYP/aug-cc-pVTZ method. This data is useful for the construction of molecular{based thermodynamic models of CO2 capture processes involving these species. The Cp data for each species over the temperature range 200 K{1500 K is presented as functions of temperature in the form of NASA seven-term polynomial expressions, permitting the set of thermochemical properties to be calculated over this temperature range. The accuracy of the G3B3 and G4 results is estimated to be 1 kcal/mol and the B3LYP/aug-cc-pVTZ results are of nferior quality..</div>

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