Pub Date : 2018-10-03DOI: 10.5772/INTECHOPEN.75977
Ş. Celasun
In this study, the settling of small particles in a non-Newtonian fluid medium is consid- ered. The simulation of this problem according to the fluid mechanics principles may be realized by the flow of a non-Newtonian fluid around a sphere falling along the centerline of a cylindrical tube. The knowledge of the rate of settling of particles in practice is particularly significant in determining the shelf life of materials such as foodstuffs, cleaning materials and many others. Thus, this problem has great importance in many natural and physical processes and in a large number of industrial applications such as chemical, genetic and biomedical engineering operations. The majority of the theoretical, experimental and numerical studies available in the literature deal with Newtonian fluids. Conversely, for non-Newtonian fluids the problem is considerably more complex. It is well-recognized that extensional behaviour in non-Newtonian fluids plays a major role in complex flows. Most non-Newtonian fluids such as polymeric solutions and melts exhibit shear-thinning behaviour. In this study it is aimed to determine the equations governing this process and some important conclusions about the properties of polymeric liquids related to their viscoelastic constitution are drawn. Effectively, it is found that for poly- meric liquids, the elastic behaviour characterized by the normal stress coefficients, implies relatively increased normal stresses with respect to the generalized Newtonian fluids, whereas the shear stresses tend to decrease, thus changing somewhat the category of the flow from shear-flow into extensional flow in a small rate. Hence, the viscoelastic property of the polymeric liquids must be stressed by their constitutive equation choice, which led us to the CEF model.
{"title":"Particle Settling in a Non-Newtonian Fluid Medium Processed by Using the CEF Model","authors":"Ş. Celasun","doi":"10.5772/INTECHOPEN.75977","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.75977","url":null,"abstract":"In this study, the settling of small particles in a non-Newtonian fluid medium is consid- ered. The simulation of this problem according to the fluid mechanics principles may be realized by the flow of a non-Newtonian fluid around a sphere falling along the centerline of a cylindrical tube. The knowledge of the rate of settling of particles in practice is particularly significant in determining the shelf life of materials such as foodstuffs, cleaning materials and many others. Thus, this problem has great importance in many natural and physical processes and in a large number of industrial applications such as chemical, genetic and biomedical engineering operations. The majority of the theoretical, experimental and numerical studies available in the literature deal with Newtonian fluids. Conversely, for non-Newtonian fluids the problem is considerably more complex. It is well-recognized that extensional behaviour in non-Newtonian fluids plays a major role in complex flows. Most non-Newtonian fluids such as polymeric solutions and melts exhibit shear-thinning behaviour. In this study it is aimed to determine the equations governing this process and some important conclusions about the properties of polymeric liquids related to their viscoelastic constitution are drawn. Effectively, it is found that for poly- meric liquids, the elastic behaviour characterized by the normal stress coefficients, implies relatively increased normal stresses with respect to the generalized Newtonian fluids, whereas the shear stresses tend to decrease, thus changing somewhat the category of the flow from shear-flow into extensional flow in a small rate. Hence, the viscoelastic property of the polymeric liquids must be stressed by their constitutive equation choice, which led us to the CEF model.","PeriodicalId":287617,"journal":{"name":"Polymer Rheology","volume":"358 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133303790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-10-03DOI: 10.5772/INTECHOPEN.75768
S. Vshivkov, E. Rusinova
The results of researches of a magnetic field effect on rheological properties of both paramagnetic, and diamagnetic polymer systems are described. Influence of intensity and the direction of power lines of the magnetic field on the viscosity of magnetic liquids and magnetorheological suspensions is analyzed. Results of theoretical researches of the magnetic field effect on the diamagnetic macromolecule orientation in solutions are discussed. The data on the influence of the magnetic field on rheological parameters of cellulose ether solutions are generalized and analyzed. The rheological parameters are compared with a change of studied system structure under magnetic field. The concentration dependences of viscosity and the sizes of supramolecular particles in solutions are compared. The rheological behavior of systems in a region of phase transitions is considered. Concentration dependences of the viscosity are described by curves with a maxi- mum which concentration corresponds to a phase transition concentration.
{"title":"Magnetorheology of Polymer Systems","authors":"S. Vshivkov, E. Rusinova","doi":"10.5772/INTECHOPEN.75768","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.75768","url":null,"abstract":"The results of researches of a magnetic field effect on rheological properties of both paramagnetic, and diamagnetic polymer systems are described. Influence of intensity and the direction of power lines of the magnetic field on the viscosity of magnetic liquids and magnetorheological suspensions is analyzed. Results of theoretical researches of the magnetic field effect on the diamagnetic macromolecule orientation in solutions are discussed. The data on the influence of the magnetic field on rheological parameters of cellulose ether solutions are generalized and analyzed. The rheological parameters are compared with a change of studied system structure under magnetic field. The concentration dependences of viscosity and the sizes of supramolecular particles in solutions are compared. The rheological behavior of systems in a region of phase transitions is considered. Concentration dependences of the viscosity are described by curves with a maxi- mum which concentration corresponds to a phase transition concentration.","PeriodicalId":287617,"journal":{"name":"Polymer Rheology","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129137719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-10-03DOI: 10.5772/INTECHOPEN.75656
C. Kukla, I. Duretek, J. Gonzalez-Gutierrez, C. Holzer
In many applications and/or manufacturing processes, highly filled polymers are necessary. One of these fields is powder metallurgy, where polymers or polymer mixtures are used to enable the shaping process within the production of the parts. Metal and also ceramic powders are mixed with different polymeric substances with a powder content of more than 50 vol%. Within the production, this mixture, called feedstock, has to flow into the final shape. Thus, for a proper understanding of the production processes, fundamental knowledge on the flow behavior of the feedstocks is required. For the rheology of polymers, several techniques together with the proper equipment are available. In the case of high viscosities, rotational and high-pressure capillary rheometers (HPCRs) are used. To gain reliable data, a proper measurement procedure is essential, which means that the operator has to have a deeper physical understanding of the material and the effects arising during the measurements. Therefore, this chapter gives an insight into rotational and high-pressure capillary rheometry with special emphasis on the behavior of polymers highly filled with stiff particles. Based thereon important remarks on the measurement equipment, procedure and evaluation of the measured data are provided.
{"title":"Rheology of Highly Filled Polymers","authors":"C. Kukla, I. Duretek, J. Gonzalez-Gutierrez, C. Holzer","doi":"10.5772/INTECHOPEN.75656","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.75656","url":null,"abstract":"In many applications and/or manufacturing processes, highly filled polymers are necessary. One of these fields is powder metallurgy, where polymers or polymer mixtures are used to enable the shaping process within the production of the parts. Metal and also ceramic powders are mixed with different polymeric substances with a powder content of more than 50 vol%. Within the production, this mixture, called feedstock, has to flow into the final shape. Thus, for a proper understanding of the production processes, fundamental knowledge on the flow behavior of the feedstocks is required. For the rheology of polymers, several techniques together with the proper equipment are available. In the case of high viscosities, rotational and high-pressure capillary rheometers (HPCRs) are used. To gain reliable data, a proper measurement procedure is essential, which means that the operator has to have a deeper physical understanding of the material and the effects arising during the measurements. Therefore, this chapter gives an insight into rotational and high-pressure capillary rheometry with special emphasis on the behavior of polymers highly filled with stiff particles. Based thereon important remarks on the measurement equipment, procedure and evaluation of the measured data are provided.","PeriodicalId":287617,"journal":{"name":"Polymer Rheology","volume":"167 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122287237","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-10-03DOI: 10.5772/INTECHOPEN.77277
L. Romero-Zerón, Saran Banthong
Supramolecular polymer networks are built up by combining multiple noncovalent interactions among macromolecules, resulting in the formation of materials with versa-tile functionality. This chapter describes an exploratory research focused on the formula- tion of a supramolecular polymer network based on reversible interactions among the main- and side chains of a mixture of xanthan gum, partly hydrolyzed polyacrylamide (HPAM), and a hydrophobically modified polyacrylamide (HMPAM) in brine solutions relevant for applications in enhanced oil recovery (EOR). The formation and charac- terization of the supramolecular network system was carried out through oscillatory rheology.
{"title":"Viscoelasticity of a Supramolecular Polymer Network and its Relevance for Enhanced Oil Recovery","authors":"L. Romero-Zerón, Saran Banthong","doi":"10.5772/INTECHOPEN.77277","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.77277","url":null,"abstract":"Supramolecular polymer networks are built up by combining multiple noncovalent interactions among macromolecules, resulting in the formation of materials with versa-tile functionality. This chapter describes an exploratory research focused on the formula- tion of a supramolecular polymer network based on reversible interactions among the main- and side chains of a mixture of xanthan gum, partly hydrolyzed polyacrylamide (HPAM), and a hydrophobically modified polyacrylamide (HMPAM) in brine solutions relevant for applications in enhanced oil recovery (EOR). The formation and charac- terization of the supramolecular network system was carried out through oscillatory rheology.","PeriodicalId":287617,"journal":{"name":"Polymer Rheology","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124034298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-10-03DOI: 10.5772/INTECHOPEN.75758
D. E. Jimenez-Sánchez, M. Calderón‐Santoyo, L. Picart-Palmade, Pedro Ulises Bautista Rosales, Julio CesarBarros-Castillo, J. A. Ragazzo‐Sánchez
Agave fructans have thermal protective and encapsulating properties as well as techno- logical functions as stabilizers. The effect of the combination of maltodextrin 10% [w/v] and native agave fructans in concentrations of 0, 2, and 4% [w/v] on the rheological prop - erties and microstructure, of spray-dried chayote, carrot, mango and pineapple powders was evaluated. The flow behavior was analyzed in a simple shear flow and low-cutting speed in the range of 5–200 s −1 . The experimental data of fresh or reconstituted juices were fitted to different flow models such as Newtonian, Bingham, and Ostwald-de-Waele. The flow behavior of all juices can be described by the Bingham model with low plastic vis -cosities; the addition of fructans and the step of spray drying had no significant influence on the plastic viscosity of juices as compared to fresh juices.
{"title":"Effect of Maltodextrin Reduction and Native Agave Fructans Addition on the Rheological Behavior of Spray-Dried Juices","authors":"D. E. Jimenez-Sánchez, M. Calderón‐Santoyo, L. Picart-Palmade, Pedro Ulises Bautista Rosales, Julio CesarBarros-Castillo, J. A. Ragazzo‐Sánchez","doi":"10.5772/INTECHOPEN.75758","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.75758","url":null,"abstract":"Agave fructans have thermal protective and encapsulating properties as well as techno- logical functions as stabilizers. The effect of the combination of maltodextrin 10% [w/v] and native agave fructans in concentrations of 0, 2, and 4% [w/v] on the rheological prop - erties and microstructure, of spray-dried chayote, carrot, mango and pineapple powders was evaluated. The flow behavior was analyzed in a simple shear flow and low-cutting speed in the range of 5–200 s −1 . The experimental data of fresh or reconstituted juices were fitted to different flow models such as Newtonian, Bingham, and Ostwald-de-Waele. The flow behavior of all juices can be described by the Bingham model with low plastic vis -cosities; the addition of fructans and the step of spray drying had no significant influence on the plastic viscosity of juices as compared to fresh juices.","PeriodicalId":287617,"journal":{"name":"Polymer Rheology","volume":"122 5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129486987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-10-03DOI: 10.5772/INTECHOPEN.77074
M. Elbadawi
Additive manufacturing techniques have recently seen an explosive growth across a myriad of fields, partly galvanised by their advantages over traditional fabrication tech niques. As with most fabrication processes, maximising efficiency is a requisite, par - ticularly if commercialisation is sought-after. Understanding how the material behaves during additive manufacturing is necessary to accomplishing said task. Accordingly, the chapter herein collates examples of where rheology is applicable in polymer-based addi tive manufacturing techniques, thereby demonstrating the necessity and utility thereto. The main focus herein will be fused deposition modelling and stereolithography additive manufacturing techniques, with examples of how both capillary and rotational rheom - eters can be utilised.
{"title":"Polymeric Additive Manufacturing: The Necessity and Utility of Rheology","authors":"M. Elbadawi","doi":"10.5772/INTECHOPEN.77074","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.77074","url":null,"abstract":"Additive manufacturing techniques have recently seen an explosive growth across a myriad of fields, partly galvanised by their advantages over traditional fabrication tech niques. As with most fabrication processes, maximising efficiency is a requisite, par - ticularly if commercialisation is sought-after. Understanding how the material behaves during additive manufacturing is necessary to accomplishing said task. Accordingly, the chapter herein collates examples of where rheology is applicable in polymer-based addi tive manufacturing techniques, thereby demonstrating the necessity and utility thereto. The main focus herein will be fused deposition modelling and stereolithography additive manufacturing techniques, with examples of how both capillary and rotational rheom - eters can be utilised.","PeriodicalId":287617,"journal":{"name":"Polymer Rheology","volume":"97 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115982985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-04-03DOI: 10.5772/INTECHOPEN.76122
I. Pérez-Reyes, René Osvaldo Vargas-Aguilar, S. Perez‐Vega, A. Ortiz-Perez
Rayleigh and Marangoni convection and rheology are linked in the thermal convection of viscoelastic fluids to some recent technological applications. Such technology developments as the ones presented here undoubtedly shall be based on interdisciplinary projects involving not only rheology or fluid mechanics but several other disciplines. Three practical applications which use Rayleigh or Marangoni convection in their working principle are presented along with some technical details. This contribution focus mainly on the physical mechanism and the involved hydrodynamics of some lab and industrial applica- tions. Finally, a short discussion on the role play by the convective mechanisms is given in order to provide integration of the exposed ideas.
{"title":"Applications of Viscoelastic Fluids Involving Hydrodynamic Stability and Heat Transfer","authors":"I. Pérez-Reyes, René Osvaldo Vargas-Aguilar, S. Perez‐Vega, A. Ortiz-Perez","doi":"10.5772/INTECHOPEN.76122","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.76122","url":null,"abstract":"Rayleigh and Marangoni convection and rheology are linked in the thermal convection of viscoelastic fluids to some recent technological applications. Such technology developments as the ones presented here undoubtedly shall be based on interdisciplinary projects involving not only rheology or fluid mechanics but several other disciplines. Three practical applications which use Rayleigh or Marangoni convection in their working principle are presented along with some technical details. This contribution focus mainly on the physical mechanism and the involved hydrodynamics of some lab and industrial applica- tions. Finally, a short discussion on the role play by the convective mechanisms is given in order to provide integration of the exposed ideas.","PeriodicalId":287617,"journal":{"name":"Polymer Rheology","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123764398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-03-14DOI: 10.5772/INTECHOPEN.75207
N. Laufer, H. Hansmann, C. Boss, Stefan Ofe
Viscosity functions of particle-filled polymer melts are shifted to higher values in com - parison with those of the unfilled polymer melts. This increase is affected by a number of factors such as the volume content, size, size distribution and the aspect ratio of the suspended particles. If interparticle interactions occur, which include the formation and breaking of agglomerates as well as the migration and rotation of particles during flow, the extent of the viscosity increase of suspensions also depends on the applied shear stress. Filler with a high aspect ratio, such as fibrous and plate-like particles, exhibits a strong tendency for interparticle interactions even at low volumetric concentrations. However, depending on the polymer matrix, spherical particles can exhibit a range of negligible interparticle interactions at low filler volume concentrations. Non-negligible interactions occur at higher filler concentrations. On the basis of the generalized interaction function , which considers the transition from negligibly interparticle interactions to the domain of non-negligibly interactions, the flow behavior of particle-filled polymer melts can be estimated. The subject of this chapter is the application of the generalized interaction function for the characterization of the flow behavior of particle-filled polyolefin melts.
{"title":"Interparticle Interaction Effects in Polymer Suspensions","authors":"N. Laufer, H. Hansmann, C. Boss, Stefan Ofe","doi":"10.5772/INTECHOPEN.75207","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.75207","url":null,"abstract":"Viscosity functions of particle-filled polymer melts are shifted to higher values in com - parison with those of the unfilled polymer melts. This increase is affected by a number of factors such as the volume content, size, size distribution and the aspect ratio of the suspended particles. If interparticle interactions occur, which include the formation and breaking of agglomerates as well as the migration and rotation of particles during flow, the extent of the viscosity increase of suspensions also depends on the applied shear stress. Filler with a high aspect ratio, such as fibrous and plate-like particles, exhibits a strong tendency for interparticle interactions even at low volumetric concentrations. However, depending on the polymer matrix, spherical particles can exhibit a range of negligible interparticle interactions at low filler volume concentrations. Non-negligible interactions occur at higher filler concentrations. On the basis of the generalized interaction function , which considers the transition from negligibly interparticle interactions to the domain of non-negligibly interactions, the flow behavior of particle-filled polymer melts can be estimated. The subject of this chapter is the application of the generalized interaction function for the characterization of the flow behavior of particle-filled polyolefin melts.","PeriodicalId":287617,"journal":{"name":"Polymer Rheology","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129426578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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