Download or read book Investigating the Degradation Resistance Improvement of the Polymeric Drag Reduction written by Esmail Abdullah Mohammed Basheer and published by . This book was released on 2013 with total page 69 pages. Available in PDF, EPUB and Kindle. Book excerpt: An important practical aspect in the application and study of drag reduction by polymer additives is the degradation of the polymer, for instance due to intense shearing, especially in circulatory flow systems. Such degradation leads to a marked loss of the drag-reducing capability of the polymer. Polymers-Surfactant complex efficacy in reducing the drag and improving the degradation resistance is a new subject in drag reduction research. Turbulent drag reduction (DR) efficacy of ionic Sodium Polystyrene Sulfonate (NaPSS) and sodium Alkylbenzene sulfonate, complexes systems regarding polymer-surfactant interaction was examined under a turbulent flow in a rotating disk apparatus, in which the DR efficacy indicates how the torque is being reduced with a tiny amount of additives under a turbulent flow at a fixed rotational speed. It was found that the addition of the surfactant to the ionic increased the polymer chain dimensions via a conformational structural change, thus enhancing the DR efficacy. Polymer-surfactant system also shows that there exists a critical polymer concentration at which the drag reduction becomes a maximum, and then above the critical concentration, the DR efficacy decreases more rapidly than that of pure polymeric systems. On the other hand, it was found that the addition of the surfactant to the ionic polymer enhance its ability to resist the degradation caused by the high shear stress in the eddy flow. The addition of sodium Alkylbenzene sulfonate to the ionic polymer was found to have higher improvement than the addition of DDAB in degradation resistance. The DR and degradation resistance efficacy induced by the polymer-surfactant mixture is found to be obvious higher than of pure polymer. In addition, the maximum of DR efficacy versus polymer concentration occurred at 700 ppm.

Download or read book Analytical and Experimental Study of Turbulent Flow Drag Reduction and Degradation with Polymer Additives written by Xin Zhang and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Flow friction reduction by polymers is widely applied in the oil and gas industry for flow enhancement or to save pumping energy. The huge benefit of this technology has attracted many researchers to investigate the phenomenon for 70 years, but its mechanism is still not clear. The objective of this thesis is to investigate flow drag reduction with polymer additives, develop predictive models for flow drag reduction and its degradation, and provide new insights into the drag reduction and degradation mechanism. The thesis starts with a semi-analytical solution for the drag reduction with polymer additives in a turbulent pipe flow. Based on the FENE-P model, the solution assumes complete laminarization and predicts the upper limitation of drag reduction in pipe flows. A new predictive model for this upper limit is developed considering viscosity ratios and the Weissenberg number - a dimensionless number related to the relaxation time of polymers. Next, a flow loop is designed and built for the experimental study of pipe flow drag reduction by polymers. Using a linear flexible polymer - polyethylene oxide (PEO) - in water, a series of turbulent flow experiments are conducted. Based on Zimm's theory and the experimental data, a correlation is developed for the drag reduction prediction from the Weissenberg number and polymer concentration in the flow. This correlation is thoroughly validated with data from the experiments and previous studies as well. To investigate the degradation of drag reduction with polymer additives, a rotational turbulent flow is first studied with a double-gap rheometer. Based on Brostow's assumption, i.e., the degradation rate of drag reduction is the same as that of the molecular weight decrease, a correlation of the degradation of drag reduction is established, along with the proposal of a new theory that the degradation is a first-order chemical reaction based on the polymer chain scission. Then, the accuracy of the Brostow's assumption is examined, and extensive experimental data indicate that it is not correct in many cases. The degradation of drag reduction with polymer additives is further analyzed from a molecular perspective. It is found that the issue with Brostow's theory is mainly because it does not consider the existence of polymer aggregates in the flow. Experimental results show that the molecular weight of the degraded polymer in the dilute solution becomes lower and the molecular weight distribution becomes narrower. An improved mechanism of drag reduction degradation considering polymer aggregate is proposed - the turbulent flow causes the chain scission of the aggregate and the degraded aggregate loses its drag-reducing ability. Finally, the mechanism of drag reduction and degradation is examined from the chemical thermodynamics and kinetics. The drag reduction phenomenon by linear flexible polymers is explained as a non-spontaneous irreversible flow-induced conformational-phase-change process that incorporates both free polymers and aggregates. The entire non-equilibrium process is due to the chain scission of polymers. This theory is shown to agree with drag reduction experimental results from a macroscopic view and polymer behaviours from microscopic views. The experimental data, predictive models, and theories developed in this thesis provide useful new insights into the design of flow drag reduction techniques and further research on this important physical phenomenon.

Download or read book Investigations of Polymeric Drag Reduction written by James P. Dickerson and published by . This book was released on 1993 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Manufacturing Science and Technology VI written by Liyanage C. de Silva and published by Trans Tech Publications Ltd. This book was released on 2015-09-02 with total page 1376 pages. Available in PDF, EPUB and Kindle. Book excerpt: Collection of selected, peer reviewed papers from the 2015 6th International Conference on Manufacturing Science and Technology (ICMST 2015), June 1-2, 2015, Bandar Seri Begawan, Brunei. The 224 papers are grouped as follows: Chapter 1: Materials and Technologies of Processing; Chapter 2: Researching and Designing of Machines and Mechanisms; Chapter 3: Applied Thermodynamics and Heat Transfer; Chapter 4: Instrumentation and Measurement Technologies, Monitoring and Fault Detection; Chapter 5: Designing and Development of Robots; Chapter 6: Mechatronics; Chapter 7: Theory and Practice of Control; Chapter 8: Civil Engineering; Chapter 9: Product Design, Product Quality and Rapid Prototyping; Chapter 10: Industrial Engineering

Download or read book Advances in Materials Sciences Energy Technology and Environmental Engineering written by Aragona Patty and published by CRC Press. This book was released on 2017-01-20 with total page 933 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 2016 International Conference on Materials Science, Energy Technology and Environmental Engineering (MSETEE 2016) took place May 28-29, 2016 in Zhuhai City, China. MSETEE 2016 brought together academics and industrial experts in the field of materials science, energy technology and environmental engineering. The primary goal of the conference was to promote research and developmental activities in these research areas and to promote scientific information interchange between researchers, developers, engineers, students, and practitioners working around the world. The conference will be held every year serving as platform for researchers to share views and experience in materials science, energy technology and environmental engineering and related areas.

Download or read book Drag Reduction and Degradation of Dilute Polymer Solutions in Turbulent Pipe Flows written by T. T. Huang and published by . This book was released on 1971 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: Drag reduction caused by dilute polyethylene oxide (POLYOX WSR-301) and anionic charged polyacrylimide (MAGNIFLOC 835A) polymer solutions was studied experimentally in 1.918- and 0.455-cm ID smooth pipes. The POLYOX solutions tested are superior in drag reduction but inferior in shear-degradation resistance compared to the MAGNIFLOC solutions at corresponding concentrations. A three-layer mean velocity profile model appears to be more consistent with current and other data than a traditional two-layer model. The onset of measured drag reduction depends upon solution concentration and is seriously affected by shear degradation. (Author).

Download or read book Rheological and Degradation Studies of Drag reducing Solutions written by Tony Moussa and published by . This book was released on 1992 with total page 706 pages. Available in PDF, EPUB and Kindle. Book excerpt: There are two main aims in this study : to carry out rheological study of drag reducing solutions, particularly the organic type at the ppm level, under different environments; to investigate the mechanisms of polymer degradation occurring at high Reynolds number turbulent pipe flow.

Download or read book Investigations on Drag Reduction by Interactions Between Polymer and Surfactant and Polymer and Polymer written by Jia Yang and published by . This book was released on 2015 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: A large amount of studies have been carried out on pipeline flow with several kinds of drag reducing agents, especially polymers and surfactants. Drag reducing agents, by definition, are additives which help suppress or eliminate turbulence in a pipeline. The mechanism and methodology of polymer only or surfactant only as drag reducing additives have been fully discovered. Whether mixed drag reducers such as polymer-surfactant or polymer-polymer systems would be effective is still not clear. In our study, polymer-surfactant and polymer-polymer mixed additives are used in order to explore the synergistic effects and interactions in pipeline flow loops. The experimental work was divided into two sections: bench-scale experiments and pilot-scale experiments. In bench-scale experiments, the properties of prepared fluids such as, surface tension, conductivity and shear viscosity were measured. Several comparison methods and calculations were applied to give better understandings of the properties resulting from mixing of polymer with surfactant and polymer with polymer. After analysis of the properties, several combinations of concentrations were selected and solutions were prepared in the main tank of pilot plant and pumped into the pipeline set-up to test the pipeline flow behaviors. Turbulence structure/Reynolds number, pipe diameter, polymer-surfactant concentration were all considered as influencing factors. Critical micelle concentration, critical aggregation concentration, polymer saturation point, the onset of drag reduction, and the interactions between the mixed additives were discussed. A comparison between pipeline results and the predictions of Blasius Equation or Dodge-Metzner Equation were also discussed.. For polymer-surfactant studies, a commonly used polymer additive - carboxylmethylcellulose (referred to as CMC which is anionic) was selected as the drag reducing agent. The performance of this polymer was investigated in the presence of six surfactants respectively - Alcohol ethoxylate (referred to as Alfonic 1412-9 and Alfonic 1412-3 which are nonionic), Aromox DMC (nonionic surfactant), Stepanol WA-100 and Stepwet DF-95 (which mainly consist sodium lauryl sulfates, anionic surfactant) and Amphosol (which is zwitterionic).The experiments were first conducted with pure CMC solution with different concentrations (100ppm, 500ppm, 700ppm and 1000ppm) as a standard. The 500ppm CMC solution was selected as the best polymer concentration with highest drag reduction efficiency. For polymer-surfactant combinations, CMC-Alfonic 1412-9, CMC-Alfonic1412-3, CMC-Stepanol and CMC-Stepwet systems were found to have significant interactions. High surfactant concentration resulted in reduction in %DR. The addition of Aromox increased the drag reduction ability and onset point when concentration was higher than the polymer saturation points. Also, both hydrophobic and electrostatic interactions were thought to have an effect on critical micelle concentration, which led to the fluctuations in the %DR. For polymer-polymer studies, PAM-PEO system at two different polymer concentrations were investigated. Overall, Pure PAM solution had much higher drag reduction ability than pure PEO solutions. Mixing them together, strong interactions occurred when PEO fraction was high (over 50%) which affected %DR and shear viscosity substantially. Power-law constants n and k were also taken into account and found to exhibit opposite trends with the increase of PEO fraction.

Download or read book Recent Advances in Material Manufacturing and Machine Learning written by Bjorn Schuller and published by CRC Press. This book was released on 2024-06-17 with total page 1016 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main aim of the 2nd international conference on recent advances in materials manufacturing and machine learning processes-2023 (RAMMML-23) is to bring together all interested academic researchers, scientists, engineers, and technocrats and provide a platform for continuous improvement of manufactur□ing, machine learning, design and materials engineering research. RAMMML 2023 received an overwhelm□ing response with more than 530 full paper submissions. After due and careful scrutiny, about 120 of them have been selected for presentation. The papers submitted have been reviewed by experts from renowned institutions, and subsequently, the authors have revised the papers, duly incorporating the suggestions of the reviewers. This has led to significant improvement in the quality of the contributions, Taylor & Francis publications, CRC Press have agreed to publish the selected proceedings of the conference in their book series of Advances in Mechanical Engineering and Interdisciplinary Sciences. This enables fast dissemina□tion of the papers worldwide and increases the scope of visibility for the research contributions of the authors.

Download or read book An Experimental Investigation of the Effect of Drag Reducing Polymer Additives on Surface Pressure Fluctuations of Bodies of Revolution with Rough Surfaces Moving Through Water written by Edward Silberman and published by . This book was released on 1978 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Turbulent Flow Drag Reduction and Degradation with Dilute Polymer Solutions written by Robert W. Paterson and published by . This book was released on 1969 with total page 197 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of the study was to attempt to find an explanation for the phenomenon first reported by Toms in 1948 in which the addition of a few grams of a long chain polymer to a million cubic centimeters of a Newtonian solvent caused a large decrease in the turbulent pipe flow pressure drop while causing only a small increase in the laminar flow viscosity. This phenomenon, which has been observed to occur for a number of different polymers and solvents, is commonly referred to as 'drag reduction with dilute polymer solutions' or 'the Toms phenomenon'. (Author).

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 548 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Drag Reduction in Pipeline by Polymer surfactant and Polymer polymer Mixtures written by Weicong Huang and published by . This book was released on 2015 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt: Extensive researches have been conducted to investigate into the drag reduction behavior of the polymer-surfactant mixture and the polymer-polymer mixture. The drag reduction effect of PAM (polyacrylamide), PEO (polyethylene oxide) and CMC (carboxymethyl cellulose) has already been studied respectively. However, the drag reduction effects of the combination of these polymers have not been studied before. It is interesting to investigate into these combinations because the synergy between different polymers can enhance the drag reduction effect under the right condition. SDS (sodium dodecyl sulfate) is a surfactant widely used in many commercially available detergents. When dissolved in water and circulated in the flow loop, the drag reduction effect of SDS has also been observed. Therefore, the combination of PAM and SDS is also worth exploring. The synergy between the polymer and the surfactant may strengthen the drag reduction effect. In this thesis, the drag reduction effects are investigated for the following combinations: the PAM-SDS system, the PAM-CMC system and the PEO-CMC system. The mixed solutions are circulated in the flow loop, where the pressure drop over a certain distance and the flow rate are recorded in order to plot the friction factor against the Reynolds number. In addition, the viscosity, conductivity and surface tension of the mixed solutions are studied at bench-scale to look for the synergy in the mixed system.

Download or read book Drag Reduction written by Robert H. J. Sellin and published by . This book was released on 1984 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Polymer Physics written by Leszek A. Utracki and published by John Wiley & Sons. This book was released on 2010-09-14 with total page 805 pages. Available in PDF, EPUB and Kindle. Book excerpt: Providing a comprehensive review of the state-of-the-art advanced research in the field, Polymer Physics explores the interrelationships among polymer structure, morphology, and physical and mechanical behavior. Featuring contributions from renowned experts, the book covers the basics of important areas in polymer physics while projecting into the future, making it a valuable resource for students and chemists, chemical engineers, materials scientists, and polymer scientists as well as professionals in related industries.

Download or read book Drag Reduction and Shear Degradation of Dilute Polymer Solutions as Measured by a Rotating Disk written by T. T. Huang and published by . This book was released on 1972 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: A saturated drag-reduction line for dilute polymer solutions is derived for a rotating disk from new velocity-similarity laws. Drag reduction measured by a rotating disk is found to have three domains--oversaturated, optimal and undersaturated. At a given boundary-layer thickness and wall-shear stress, the drag-reduction increases with increasing concentration in the undersaturated domain, and the drag reduction does not increase with increasing concentration in the oversaturated domain. The boundary between the two domains is the optimal drag reduction, which is determined by the type of polymer and its concentration and a Reynolds number based on shear velocity and disk radius or boundary-layer thickness. (Author).

Download or read book Turbulent Flow Drag reduction by Dilute Poly ethylene Oxide Solutions in Capillary Tubes written by Ira Michael Felsen and published by . This book was released on 1971 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study was initiated to investigate turbulent flow drag-reduction by dilute poly(ethylene oxide) solutions in capillary tubes and thereby elucidate the mechanism of drag-reduction through interpretation of the experimental results. Flow through capillary tubes was chosen as a means to (1) obtain a large ratio of solid surface area to fluid volume, and (2) obtain high shear stresses at low Reynolds numbers. This allowed investigation of surface effects and polymer degradation as a function of a number of variables which are known to influence drag-reduction. (Author).