Corresponding author: Igor A. Chusov (igrch@mail.ru)
Academic editor: Boris Balakin
The paper presents recommended correlations for calculating the thermodynamic and transport properties of
The eutectic leadbismuth alloy has relatively recently begun to be used as a coolant mainly in transportable nuclear power plants (
A generalized systematic analysis of the experimental results related to the transport and thermodynamic properties of
There are foreign publications summarizing the results obtained by various authors (
The emergence of new data resulted in the need to clarify and correct existing correlations. A calculation analysis was performed for the following parameters: density, dynamic viscosity, specific heat, thermal conductivity, surface tension, specific electrical resistance, and speed of sound in the alloy.
Since 2020, the correlations proposed in this work have been recommended by the Rosatom State Atomic Energy Corporation for calculating the thermodynamic properties of
The thermodynamic and transport properties of the leadbismuth eutectic alloy were evaluated on the basis of experimental data presented in 39 works. The authors of this work had information about 1103 experimental points. A direct assessment was performed on 1076 points. Table
Data on sources and temperature ranges.
Parameter  Number of works*  Period, yrs  Temperature range, K  Total number of points  Number of evaluated points 

Density  12  1952–2015  400–1225  594  594 
Dynamic viscosity  8  1954–2015  400–1300  155  137 
Specific heat  3  1954–1973  400–950  19  11 
Thermal conductivity  9  1923–2008  400–1000  122  121 
Surface tension  10  1951–2008  400–1250  77  77 
Specific electrical resistance  3  1954–2008  400–1050  24  24 
Speed of sound  4  1975–2009  400–1400  112  112 
* The number of works based on which the analysis was performed
To determine the comparative accuracy of the calculated properties according to the recommended correlations, calculations were performed using the formulas from the reference book published by the Nuclear Energy Agency (
Relative errors of regression equations (1)–(7) for the leadbismuth eutectic parameters in comparison with the data from (
Parameter  This paper  Kirillov ( 


Density  0.25  0.33  0.29 
Dynamic viscosity  3.22  24.0  4.95 
Specific heat  1.83  2.07  37.86 
Thermal conductivity  5.3  –  3.87 
Surface tension  1.21  1.17  1.4 
Specific electrical resistance  2.43  3.99  2.5 
Local speed of sound  0.4  –  0.8 
The recommended correlation for the density of
ρ = 1.1·10^{4} – 1.223·
where
Temperaturedensity dependence of
µ = 8.65×10^{–4} + 1.77·10^{–2}×exp(–
where µ is the dynamic viscosity, Pa×s. Relation (2) is applicable in the temperature range of 400–1300 K.
The calculation results for relation (2) are graphically presented in Fig.
Temperaturedynamic viscosity dependence of
The applicability range is 400–950 K. The experimental data are shown in Fig.
Temperaturespecific heat dependence of
It should be especially noted that obtaining experimental data on the specific heat of
Currently, there is no unambiguous theory of thermal conductivity. In the most general case, thermal conductivity depends on temperature, chemical composition, etc.
λ = 3.615 + 0.0172
where λ is the thermal conductivity, W/(m×K). The correlation is applicable in the range of 400–1000 K. As a whole, 122 experimental points were obtained in the above studies. The calculated estimation was performed on 121 experimental points.
The graph for equation (4) is shown in Fig.
Temperaturethermal conductivity dependence of
It should be noted that the experimental data presented in this figure diverge on average by 25%. This spread is apparently caused by a high content of impurities in bismuth. Unfortunately, in the majority of the experimental studies, there is no information on the percentage of impurities in the initial experimental material. The authors of this work could only assume their presence. Based on this, the fundamental arguments in selecting data for the assessment were the facts of the deviation of the trend of the experimental data presented in a particular work from the general trend and the explicit “loss” of individual points from the general data array.
σ = (441.1 – 0.0711·
where σ is the surface tension coefficient, N/m. The temperature range is 400–1370 K.
The graph for equation (5) and experimental data are shown in Fig.
Temperaturesurface tension dependence of
where
The graph for equation (6) and experimental data are shown in Fig.
Temperatureelectrical resistance dependence of
where
The calculation results for relation (7) are presented in Fig.
Temperaturespeed of sound dependence of
The values of relative errors for relations (1)–(7) and the errors given in (
The paper presents semiempirical dependences for calculating several transport and thermodynamic properties of
* Russian text published: Izvestiya vuzov. Yadernaya Energetika (ISSN 02043327), 2020, n. 1, pp. 107–120.