STUDY OF RHEOLOGICAL PROPERTIES OF PARAFFIN OIL MIXTURE

Abstract

In experiments on cavitation effect on oil, rheological properties (density, dynamic viscosity coefficient, oil composition, freezing point and shear stress on the wall) of  high-viscosity, low-freezing oils from the Kalamkas and Karazhanbas fields, as well as high freezing paraffinic oils from the Uzen and Zhetybay fields were studied. The ratio of oils in this case is: Zhetybay-Uzen - 65%, Karazhanbas-Kalamkas – 35%. From a ready mixture of oils in the volume of 10 liters, in accordance with the sampling method according to GOST 2517-85, a sample of oil in the amount of 0.5 liters is taken for the initial analysis of the mixture of oils according to the measured values. Then the ready mixture of oils, heated to the required 
temperature, is loaded into the receiving tank of the unit and mixed with a mixer to obtain a homogeneous mixture. The mixed oil mixture is pumped by a gear pump and fed to the cavitation unit. In this case, the movable rod regulates the oil pressure at the inlet to the confuser and changes the cavitation mode. After the oil passes through the diffuser, a sample of oil is taken for analysis using a special device. The processed oil is again fed to the receiving tank and then sent for secondary processing using a gear pump. The ultimate shear stress of oils before and after cavitation at different temperatures was determined. It was found that at temperatures 
below 30 oC and above, oils are Newtonian fluids. Pseudoplastic fluids have rheological characteristics that do not depend on time, and for such fluids, the yield point is not detected.