The shear viscosity tensor of a superfluid Fermi gas in a p-wave state with weak interactions was investigated using the Boltzmann equation at low temperatures. Therefore, transition probabilities of the binary collision, decay, and coalescence processes were considered for this purpose. Theoretically, the dominant processes at low temperatures find to be the binary ones, whereas the elements of the shear viscosity (i.e., ) report to be proportional to . Moreover, behaved as , and  was proportional to .

Gas viscosity is one of the most important parameters in petroleum engineering affecting fluid flow in porous media, well, and pipelines. Therefore, it is important to use an accurate value in any ranges of operational pressure and temperature. Gas viscosity is measurable in laboratories but it is costly and time consuming. Also, in Iran, there is no apparatus to measure gas viscosity accurately in laboratories; thus engineers rely on empirical correlations to estimate gas viscosity. In this study, a novel method is used to predict hydrocarbon gas viscosity. This new gas viscosity correlation is developed using artificial neural network, statistical techniques, and a non-linear optimization. Moreover, the validation of this correlation has been approved. The results show that this model has more accuracy compared to other ones for a massive data set.

In this paper the application of centrifugal type gas separator as a part of submersible electric screw pumping unit is considered. A number of bench tests have been carried out to study the centrifugal gas separator on viscous gas-liquid mixture. Calculation of the dependence of delivery on the developed pressure of a single screw pump at the angular speed of rotation of the rotor 225 rpm for different gas content has been made. Also, characteristic curves of gas separators of groups 5 and 5A at different gas contents and different viscosity of gas-liquid mixture are obtained. A methodology for bench testing of gas separators has been developed, which takes into account the influence of gas-liquid mixture properties, changes in the angular speed of the electric motor shaft rotation, and natural separation parameters. The operating parameters of a gas separator of group 5A were determined experimentally, taking into account a residual gas content of 50%, in the range of angular speeds of 252 – 1000 rpm (4.2 – 16.7 Hz).

Compressibility factor and viscosity of natural gasses are of great importance in petroleum and chemical engineering. To calculate the natural gas properties in the pipelines, storage systems and reservoirs, the exact values of gas compressibility factor and viscosity are required. A new method that allows accurate determination of compressibility factor and gas viscosity for all types of: sweet, sour, condensate and acid gases in a wide range of pressure and temperature conditions are presented here. The sizable data base of experimental Z factor and experimental gas viscosity measurements is collected from the available related literature. This newly developed method is tested by implementation of combined fuzzy inference system and Genetic Algorithm. The natural gas compressibility factor and viscosity as a function of gas composition, pressure, temperature and molecular weight of C7+ can be predicted through this model. The accuracy of this proposed model is compared with some commonly applied empirical correlations. The average absolute relative error here is 1.28 % and 0.57% for Z factor and gas viscosity, respectively.

During the operation of the floating ring gas film seal, a certain amount of heat is generated inside the seal gap, giving rise to thermal deformation of the seal rings, and further leading to operation unstable and increased leakage rate. Based on the gas lubrication theory, the control equations of gas pressure and gas film thickness of the floating ring gas film seal are obtained. And the energy and temperature-viscosity equation are also introduced. The above equations were solved by the finite difference method and their correctness was verified by experiments. The variation of opening force, leakage rate, friction force, and gas film temperature rise with rotating speed, inlet pressure, and eccentricity were analyzed. The results reveal that, for leakage rate, the difference between the modeled and tested values is only 2. 94% at high speeds, taking into account the influence of the temperature-viscosity effect. The experiment substantiates that the temperature-viscosity effect model is scientifically valid. Operation parameters also have different effects on sealing performance. Compared with isothermal flow, the pressure distribution in the gas film flow field will change significantly with increasing gas temperature, which means that the temperature-viscosity effect cannot be neglected in the flow field calculation. These results provide grounds for further study of the thermoelastic effect of air film seal of floating ring and have important engineering significance.

In this paper the effects of flow viscosity on the property of fluid flow through gas turbine blading in two dimensional modes and for a sample of blade was investigated. The fluid used in this research is air which is considered as ideal gas for steady state flow condition. This analysis is done by a computer program which is developed for this purpose. This program has two arithmetic stages, so that at first step the inviscid part is computed then obtained data is used to compute the Viscose part one. This analysis is done for two cases separately and comparison results are shown as tables and graphs. The discussed properties in this paper are: Mach number, Pressure and Temperature.