Effects of optimal concentrations of asphalt-tar substances and wax on the rheological characteristics of high-viscosity petroleum during transport in large pipelines

One of the methods of influence on rheological properties of heavy high-viscosity crude oils is ultrasonic treatment. Ultrasonic treatment allows reducing the viscosity of crude oil and, therefore, reducing the costs of its production and transportation. In this paper, the influence of ultrasonic treatment on the rheological characteristics of crude oil (sample No. 1 API = 29.1, sample No. 2 API = 15.9) was investigated. An experimental method was developed. Experimental studies were carried out using the Physica MCR 102 rheometer. The influence of the intensity and duration of ultrasonic treatment on the viscosity of the initial crude oils was studied for 24 h. In addition, the rheological characteristics of the treated oil were investigated after its natural cooling to 293 K. The results are compared with similar results for thermal heating.

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The Assessment of the Rheological Characteristics of Various Polyborosiloxane/Grit Mixtures as Utilized in the Abrasive Flow Machining Process

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1243/pime_proc_1995_209_171_02 ◽

1995 ◽

Vol 209 (6) ◽

pp. 409-418 ◽

Cited By ~ 31

Author(s):

P J Davies ◽

A J Fletcher

Keyword(s):

Pressure Drop ◽

Mesh Size ◽

High Viscosity ◽

Important Variable ◽

Machining Process ◽

Complex Nature ◽

Machining Parameters ◽

Rheological Characteristics ◽

Abrasive Flow Machining ◽

Low Viscosity

Abrasive flow machining (AFM) is a non-traditional machining process used since the mid-1960s, which utilizes a mixture of polyborosiloxane and abrasive grit additions extruded across surfaces and edges and through component cavities. The machining mechanism of this process is still only partially understood due to its complex nature, and the present work undertook to investigate the relationship between the rheological characteristics of several mixtures and their associated machining parameters. This paper addresses those rheological characteristics of the various mixtures used in the present work. Experiments were conducted using low viscosity (LV), medium viscosity (MV) and high viscosity (HV) polyborosiloxane base media, in conjunction with silicon carbide abrasive grit of 60 and 100 mesh size, the ratios of the grit to base polymer used being 0, 1 and 2. The test pieces used were mild steel dies and the equipment used to conduct the experiments was an Extrude Hone mark 7 A machine. The results have shown that progression from low to high viscosity base medium produces a reduction in the temperature rise (for example from 32 to 10°C over 30 cycles) as well as an increase in both the average pressure drop across the die (for example from 1700 to 2674 kPa over 30 cycles) and the processing time (for example from 28 to 406 s over 30 cycles). In addition, the temperature of the medium is seen to be an important variable in the AFM process due to its effects on viscosity. Furthermore, as the usage of a medium increases the viscosity and pressure drop across the die increase.

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TECHNOLOGICAL PIPELINES CALCUCATION FEATURES FOR HIGH-VISION OIL PRODUCTS TRANSPORTATION

Metallurgicheskaya i gornorudnaya promyshlennost ◽

10.33101/s064567890 ◽

2018 ◽

pp. 49-56

Author(s):

Ye.V. Semenenko ◽

Ye.S. Lapshin ◽

M.M. Liah ◽

S.V. Dziuba

Keyword(s):

Tangential Stress ◽

Newtonian Fluid ◽

High Viscosity ◽

Rheological Characteristics ◽

Main Pipelines ◽

Transportation Modes ◽

Modern Methods ◽

Operation Parameters ◽

Newtonian Liquids ◽

Technological Calculation

Purpose. Scientific basis substantiation for the technological calculation of main pipelines. Which are pumping high viscosity non-Newtonian liquids, taking into account the peculiarities behavior of the full Buckingham equation solution in various intervals of the values included in it. Methodology. The modern methods analysis for calculating rational parameters of the high viscosity non-Newtonian fluid viscosity transportation modes which made it possible to substantiate the specificity of the rheological characteristics of these liquids, taking into account the possibility of controlling their rheological properties by introducing surface-active reagents or a heterogeneous medium of lower viscosity. Findings. The scientific and methodological support for the calculation of the rational parameters of high viscosity non-Newtonian liquids transportation modes for main pipelines is substantiated, in order to ensure an increase in the efficiency of their operation. At the same time, the dependencies proposed in the work take into account the possibility of evaluating changes in the main pipelines operation parameters and modes with forced regulation by the rheological parameters of the pumped medium. Originality. Based on the modern methods of technological calculations of the main pipelines operation parameters analysis, the hydrodynamic feature of the high viscosity non-Newtonian fluids is determined, which is that the dependence of the hydraulic slope on the initial tangential stress and costs are expressed by a linear superposition of the terms containing these values, and the proportional coefficients are independent from the rheological characteristics of the environment, the properties of the transported and the pipeline diameter. Practical value. It consists in improved methods for calculating rational parameters for the transportation of slurries, slurries and high viscosity liquids in main pipelines. These methods allow to determine the pipeline diameter value, the choice of pumps indicators, taking into account the effective viscosity, as well as the initial tangential stress of high viscosity non-Newtonian fluid in order to reduce the energy intensity of transportation, save resources and improve the environmental safety of industrial areas. Key words: high viscosity non-Newtonian fluid, rheological characteristics, main pipeline, technological calculation

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Synthesis and rheological characteristics of high viscosity linear polysiloxane carrier fluid-based magnetorheological fluids

Smart Materials and Structures ◽

10.1088/1361-665x/ac3da1 ◽

2021 ◽

Author(s):

Lei Xie ◽

Young-Tai Choi ◽

Changrong Liao ◽

Zhi Zeng ◽

Norman M Wereley

Keyword(s):

Shear Rate ◽

Rheological Properties ◽

Particle Concentration ◽

High Viscosity ◽

Magnetorheological Fluids ◽

Test Method ◽

Fluid Viscosity ◽

Rheological Characteristics ◽

Carrier Fluid ◽

Field Dependent

Abstract This study addresses the synthesis and field-dependent rheological characteristics of novel magnetorheological fluids (MRFs) using high viscosity linear polysiloxanes (HVLPs) as a carrier fluid. First of all, the components and preparation of novel HVLP-based MRFs (HVLP MRFs) were explained in detail and the microscopic images of each component were taken by using scanning electron microscope (SEM). Four HVLP MRF samples with different particle volume fractions of 10, 15, 20, and 26 vol% in the same HVLP carrier fluid viscosity of 800 Pa·s were synthesized to investigate the particle concentration effect on their field-dependent rheological properties. In order to understand the effect of the carrier fluid viscosity, two more HVLP MRF samples with different HVLP viscosities of 140 and 440 Pa·s in the same particle concentration of 26 vol% were also fabricated. In addition, the temperature effect on HVLP MRFs was studied by using the sample with 26 vol% in particle concentration and 140 Pa·s in HVLP viscosity under different operating temperatures of 25, 40, 55 and 70℃. The flow curve measurements of shear stress versus shear rate in the magnetic fields were conducted by using controlled shear rate (CSR) test method with a commercial parallel-plate type rotational rheometer. From the flow curves, the field-dependent rheological properties of HVLP MRFs including static and dynamic yield stresses and the dynamic range (ratio of field on to field off yield stress) were obtained. These material characteristics were then examined as a function of varying particle concentration, varying carrier fluid viscosity, and varying temperature. A conventional commercial MRF (i.e., Lord MRF-126CD) was adopted for comparison study and its rheological properties under different temperatures were also measured and compared with those of HVLP MRFs. Using HVLP carrier fluids, it was demonstrated that the HVLP MRFs exhibited much greater suspension stability than the conventional commercial MRF.

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