Thermophysical properties of liquids

Liquid viscosity is one of the most difficult properties to calculate with accuracy, yet it has an important role in the calculation of heat transfer coefficients and pressure drop. No single method is satisfactory for all temperature and viscosity ranges. We will distinguish three cases for pure hydrocarbons and petroleum fractions  

Chapter 4. METHODS FOR THE CALCULATION OF HYDROCARBON PHYSICAL PROPERTIES 127 

As a liquid approaches its critical conditions, its density decreases and consequently the distance between molecules increases resulting in a rapid decrease in viscosity. 

Viscosity can be expressed as a function of reduced density to which the viscosity of the ideal gas must by added. We will use the formulation proposed by Dean and Stiel in 1965  

The coefficient can be modified to include an experimental vTscdsIly af a reduced temperature between 0.85 and 0.95. This method applies only if the reduced density is less than 2.5 and the reduced temperature is greater than 0.85. Its average accuracy is about 30%. 

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For the deformation of droplets of normal liquids at low impact velocities on a horizontal plane surface without phase change, Tan et al)513 developed a physical-mathematical model with a droplet falling from a certain height under the influence of gravity. They derived quantitative relations for the dimensions of the deformed droplet, including the effects of initial droplet diameter, height of fall, and thermophysical properties of liquid. In this model, the behavior of droplet deformation was assumed to be governed by... 

It should be noted that it is difficult to obtain models that can accurately predict thermal contact resistance and rapid solidification parameters, in addition to the difficulties in obtaining thermophysical properties of liquid metals/alloys, especially refractory metals/al-loys. These make the precise numerical modeling of flattening processes of molten metal droplets extremely difficult. Therefore, experimental studies are required. However, the scaling of the experimental results for millimeter-sized droplets to micrometer-sized droplets under rapid solidification conditions seems to be questionable if not impossible,13901 while experimental studies of micrometer-sized droplets under rapid solidification conditions are very difficult, and only inconclusive, sparse and scattered data are available. 

Vargaflik, N. B., TABLES ON THE THERMOPHYSICAL PROPERTIES OF LIQUIDS AND GASES. 2nd ed., English translation. Hemisphere Publishing Corporation, New York, NY (1975, 1983). 

N. B. Vargaftik Tables on the Thermophysical Properties of Liquids and Gases , John Wiley, New York 1975. 

Calculated from values of pressure, volume (or density), and temperature in Vasserman, Kazavchinskll, and Rabinovich, Thermaphysical Prtypertws of Air and Air Components, Moscow, Nauka, 1966, and NBS-NSF Trans. TT 70-50095,1971 and Vasserman and Rabinovich, Thermophysical Properties of Liquid Air and Its Components, Moscow, 1968, and NBS-NSF Trans. 69-55092,1970. 

Converted from tables in Vargaftik, Tables of the Thermophysical Properties of Liquids and Gases, Nauka, Moscow, 1972, and Hemisphere, Washington, 1975. m = melting point. The notation 1.78.-13 signifies 1.78 x 10". ... 

Gold PI, Ogle GJ. Estimating thermophysical properties of liquids Part 4. Boiling, freezing and triple-point temperatures. Chem Eng 1969 76. 

Not much is known about the thermophysical properties of liquid metals, especially the transport properties such as chemical and thermal diffusivities. The existing data are sparse and the scatter makes it difficult to make an accurate determination of the temperature dependency of these properties. This situation was the motivation for Froberg s experiment on Space-lab-1 in which he measured the temperature dependence of the self-diffusion of Sn from 240°C to 1250°C. He found that the diffusion coefficients were 30-50% lower than the accepted values and seemed to follow a 7 dependence as opposed to the Arrhenius behavior observed in solid state diffusion. ... 

Vargaftik NB (1975) Tables on the thermophysical properties of liquids and gases, 2nd in., Wiley, New York... 

Skripov, V. P., Sinitsyn, E. N., Pavlov, P. A., Ermakov, G. V., Muratov, G. N., Bulanov, N. V., Baidakov, V. G. (1988) Thermophysical Properties of Liquids in the Metastable (Superheated) State. Gordon and Breach Science Publishers New York, London, Paris, Montreux, Tokyo, Melbourne)... 

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