Thermal conductivities of aqueous

The thermal conductivity of aqueous electrolyte solutions is typically described at room temperature by the following empirical equation ... 

This is confirmed by the work of Christiansen and Craig [11], Oliver and Jenson [12], and Yoo [13]. These investigators found that the thermal conductivities of dilute aqueous solutions of Carbopol-934, carboxymethyl cellulose (CMC), polyethylene oxide, and polyacrylamide are no more than 5 percent lower than those of pure water at corresponding temperature. However, Bellet et al. [14] observed substantial decreases in the thermal conductivity measurements for much higher concentrations of aqueous solutions of Carbopol-960 and CMC (i.e., beyond 10 to 15 percent by weight). Lee and Irvine [15] reported that the thermal conductivity of aqueous polyacrylamide solutions was dependent on the shear rate. 

Lee et al. [16] measured thermal conductivities of various nonnewtonian fluids at four different temperatures using a conventional thermal conductivity cell. These results, shown in Table 10.2, support the common practice of assuming that the thermal conductivity of aqueous polymer solution is equal to that of pure water of a corresponding temperature if the concentration of the polymer is less than 10,000 wppm (that is, 1 percent by weight). 

Table 7.30 Thermal Conductivity of Aqueous Propylene Glycol Solutions at Various Temperatures (19)...

THERMAL CONDUCTIVITY OF AQUEOUS SOLUTIONS OF ORGANIC LIQUIDS. 

THERMAL CONDUCTIVITY OF AQUEOUS SOLUTIONS OF ORGANIC LIQUIDS. //ENGLISH TRANSLATION OF ZH. FIZ. KHIM. 40... 

THERMAL CONDUCTIVITY OF AQUEOUS AND NONAQUEOUS SOLUTIONS OF ORGANIC ACIDS. 

Riedel L. (1950) "Thermal conductivity of aqueous caustic soda solutions". Chem. Ing. Tech. 22 p54. 

A literature survey revealed that the number of measurements reported for the thermal conductivity of such aqueous systems rmder pressure and at high temperature (above 200 °C), is rather limited. Fmihermore, the scatter of the reported data is quite large (up to 6%) and exceeds the quoted mutual rmcertainties of the authors (about 1-2%). This chapter aims to provide the readers with a review of the available experimental data sets on the thermal conductivity of aqueous systems at high temperatures (above 200 °C) and high pressures, to present a critical analysis of the estimation, correlation, and prediction methods, to select the most reliable data sets and to propose preliminary recommendations. 

In Table 5.1, it can be seen that 48 out of 103 data sets of thermal conductivity of aqueous solutions at high temperatures, were derived with the parallel-plate technique. This technique for the measurement of the thermal conductivity has been in use for almost a century (Todd, 1909), and it has in feet been considerably improved over the years (Sengers, 1962 Michels et al, 1962, 1963 Sirota et al, 1974 Amirkhanov and Adamov, 1963 Amirkhanov et al, 1974 Guseynov, 1987, 1989 Moster et al, 1989 and... 

After a careful analysis of the uncertainties all of the quantities (Abdulagatov et al, 2004a) entering Equation (5.17), it is estimated that the combined relative uncertainty in the thermal conductivity measurements was 2%. This thermal conductivity apparatus has also been successfully employed by Akhundov et al. (1994), Akhmedova et al (1995), and Azizov (1999), to study the thermal conductivity of aqueous Li2S04, Zn(N03)2, Ca(NOs)2, and Mg(NOs)2 solutions at temperatures up to 590 K and pressures up to 40 MPa. 

Only two investigators (DiGuilio et ah, 1990 Bleazard et al, 1994 and Bleazard and Teja, 1995) employed the transient hot-wire technique for the measurement of the thermal conductivity of aqueous solutions above 200 °C. Hence this technique will only be briefly described here. 

In this section the different techniques (parallel-plate, coaxial-cyUnder, and transient hot-wire) employed to measiue the thermal conductivity of aqueous solutions at high temperatures were discussed. In general, the uncertainty of all the available experimental thermal conductivity data derived with the first two methods should be within 1... 

Based on the aforementioned discussion, DiGuilio et al. (1990), DiGuilio and Teja (1992), Bleazard et al. (1994), and Bleazard and Teja (1995), proposed a simple scheme for the prediction of the thermal conductivity of aqueous solutions at high pressures. According to this scheme, the thermal conductivity of the aqueous solution at a high pressure is obtained by the equivalent one at atmospheric pressure by multiplying it with the ratio of the thermal conductivity of water at that high pressure over its value at atmospheric pressure. This idea produced values that deviated by up to 2% from the experimental data. 

Chiquillo (1967) proposed the following equation for the concentration dependence of the thermal conductivity of aqueous solutions... 

Chiquillo, A. (1967) Measurements of the Relative Thermal Conductivity of Aqueous Salt Solutions with a Transient Hot-Wire Method. Juris Druck-tVerlag Zurich. 

Thermal Conductivities of Aqueous Solutions of Citric Acid... 

Thermal conductivities of aqueous solutions of citric acid X T-,m) are only known from the Averbukh et al. [80] investigation, for 0.10increase with increasing temperature T and decrease with increasing concentration w. The change inl(7 ffz) values in dilute solutions is significant considering high values of thermal conductivity of pure water [179]... 

Ramires, M. L. V., Nieto de Castro, C. A., Fareleira, J. Wakeham, W. A. (1994). Thermal-conductivity of aqueous sodium-chloiide solutions. Journal of Chemical and... 

Thermal conductimties of aqueous glycol solutions Thermal conductivities of aqueous glycol solutions are presented in Figure 5.5A-C [3],... 

Figure 5.5A Thermal conductivities of aqueous ethylene glycol solutions. (Courtesy Gas Processing Supplier Association.)...

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