Static Rheological Study of Ocimum basilicum Seed Gum

2015 ◽  
Vol 11 (1) ◽  
pp. 97-103 ◽  
Author(s):  
Fakhreddin Salehi ◽  
Mahdi Kashaninejad
Keyword(s):  
Power Law ◽  
Flow Behavior ◽  
Shear Thinning ◽  
Power Law Model ◽  
Rotational Viscometer ◽  
Flow Behavior Index ◽  
Consistency Coefficient ◽  
Salt Addition ◽  
Seed Gum ◽  
Behavior Index

Abstract A rotational viscometer was used to investigate the effect of different sugars (sucrose, glucose, fructose and lactose, 1–4% w/w) and salts (NaCl and CaCl2, 0.1–1% w/w), on rheological properties of Basil seed gum (BSG). The viscosity was dependent on type of sugar and salt addition. Interactions between BSG gum and sugars improved the viscosity of solutions, whereas the viscosity of the BSG solutions decreased in the presence of salts. Power law model well-described non-Newtonian shear thinning behavior of BSG. The consistency index was influenced by the sugars and salts content. Addition of sucrose, glucose, lactose and salts to BSG led to increases in flow behavior index (less shear thinning solutions), whereas fructose increased shear thinning of solutions. Flow behavior index values of the power law model vary as follows: 0.43–0.49, 0.53–0.64, 0.21–0.26, and 0.57–0.67 for sucrose, glucose, fructose and lactose, respectively. The consistency coefficient (k) of BSG was affected by sugars and salts. It decreased from 0.14 to 0.09 Pa.sn with increasing CaCl2 from 0 to 4% w/w (20°C, 0.2% w/w BSG). The consistency coefficient values vary as follows: 0.094–0.119, 0.075–0.098, 0.257–0.484, and 0.056–0.074 for sucrose, glucose, fructose and lactose, respectively.

Rheological Characterization and Sensory Evaluation of a Typical Soft Ice Cream Made with Selected Food Hydrocolloids

2010 ◽  
Vol 16 (1) ◽  
pp. 79-88 ◽  
Author(s):  
M. BahramParvar ◽  
S.M.A. Razavi ◽  
M.H.H. Khodaparast
Keyword(s):  
Quality Evaluation ◽  
Flow Behavior ◽  
Ice Cream ◽  
Rheological Characteristics ◽  
Power Law Model ◽  
Rheological Characterization ◽  
Flow Behavior Index ◽  
Consistency Coefficient ◽  
Seed Gum ◽  
Behavior Index

The effect of two novel hydrocolloids known as Balangu seed gum (BSG) and palmate-tuber salep (PTS) with carboxymethylcellulose (CMC) on the rheological characteristics of a typical soft ice cream was studied. The power law model well described the flow behavior of mixes with a high correlation coefficient (r). The flow behavior index was in the range of 0.450-1.154, while the consistency coefficient varied from 0.051 to 6.822 Pa sn. All mixes showed a pseudoplastic behavior except the mix containing 0.3% PTS, which was found to have a slightly dilatant characteristic. An increase in the concentration was accompanied by an increase in the pseudoplasticity and consistency coefficient. The effect of selected gums on some sensory properties of a soft ice cream such as viscosity, coldness, firmness, degree of smoothness (coarseness), liquefying rate, body and texture and total acceptance has also been investigated in this work. The correlation between the apparent viscosity and sensory attributes has been determined because of the importance of viscosity in the quality evaluation of an ice cream. Taking into account the commercial ice cream properties, a 0.4% BSG gum concentration may be recommended.

Electroosmotic Flow of Power-Law Fluids in a Slit Microchannel

2009 ◽  
Author(s):  
Cunlu Zhao ◽  
Chun Yang
Keyword(s):  
Shear Stress ◽  
Double Layer ◽  
Power Law ◽  
Dynamic Viscosity ◽  
Electroosmotic Flow ◽  
Flow Behavior ◽  
Flow Behavior Index ◽  
Power Law Fluids ◽  
Hyperbolic Cosine ◽  
Behavior Index

Electroosmotic flow of power-law fluids in a slit channel is analyzed. The governing equations including the linearized Poisson–Boltzmann equation, the Cauchy momentum equation and the continuity equation are solved to seek analytical expressions for the shear stress, dynamic viscosity and velocity distributions. Specifically, exact solutions of the velocity distributions are explicitly found for several special values of the flow behavior index. Furthermore, with the implementation of an approximate scheme for the hyperbolic cosine function, approximate solutions of the velocity distributions are obtained. In addition, a mathematical expression for the average electroosmotic velocity is derived for large values of the dimensionless electrokinetic parameter, κH, in a fashion similar to the Smoluchowski equation. Hence, a generalized Smoluchowski velocity is introduced by taking into account contributions due to the finite thickness of the electric double layer and the flow behavior index of power-law fluids. Finally, calculations are performed to examine the effects of κH, flow behavior index, double layer thickness, and applied electric field on the shear stress, dynamic viscosity, velocity distribution, and average velocity/flow rate of the electroosmotic flow of power-law fluids.

Non-Newtonian Fluid Flow and Heat Transfer in a Semicircular Microtube Induced by Electroosmosis and Pressure Gradient

2018 ◽  
Vol 140 (12) ◽  
Author(s):  
Mehdi Karabi ◽  
Ali Jabari Moghadam
Keyword(s):  
Nusselt Number ◽  
Pressure Gradient ◽  
Flow Behavior ◽  
Velocity Ratio ◽  
Shear Thinning ◽  
Fluid Viscosity ◽  
Flow Behavior Index ◽  
Shear Thinning Fluids ◽  
Power Law Fluids ◽  
Behavior Index

The hydrodynamic and thermal characteristics of electroosmotic and pressure-driven flows of power-law fluids are examined in a semicircular microchannel under the constant wall heat flux condition. For sufficiently large values of the electrokinetic radius, the Debye length is thin; the active flow within the electric double layer (EDL) drags the rest of the liquid due to frictional forces arising from the fluid viscosity, and consequently a plug-like velocity profile is attained. The velocity ratio can affect the pure electrokinetic flow as well as the flow rate depending on the applied pressure gradient direction. Since the effective viscosity of shear-thinning fluids near the wall is quite small compared to the shear-thickening fluids, the former exhibits higher dimensionless velocities than the later close to the wall; the reverse is true at the middle section. Poiseuille number increases with increasing the flow behavior index and/or the electrokinetic radius. Due to the comparatively stronger axial advection and radial diffusion in shear-thinning fluids, better temperature uniformity is achieved in the channel. Reduction of Nusselt number continues as far as the fully developed region where it remains unchanged; as the electrokinetic radius tends to infinity, Nusselt number approaches a particular value (not depending on the flow behavior index).

scholarly journals Uncertainties quantification and modelling of different rheological models in estimation of pressure losses during drilling operation

2018 ◽  
Vol 7 (2) ◽  
pp. 694 ◽  
Author(s):  
Anawe P. A. L ◽  
Folayan J. Adewale
Keyword(s):  
Power Law ◽  
Averaging Method ◽  
Graphical Method ◽  
Flow Behavior ◽  
Drilling Fluids ◽  
Flow Behavior Index ◽  
Rheological Models ◽  
Pressure Losses ◽  
Pump Pressure ◽  
Behavior Index

The determination of pressure losses in the drill pipe and annulus with a very high degree of precision and accuracy is sacrosanct for proper pump operating conditions and correct bit nozzle sizes for maximum jet impact and forestalling of possible kicks and eventual blow outs during drilling operation. The two major uncertainties in pump pressure estimation that are being addressed in this research work are the flow behavior index (n) and the consistency index factor (k). It is in this light that the accuracy of various rheological models in predicting pump pressure losses as well as the uncertainties associated with each model was investigated. In order to come by with a decisive conclusion, two synthetic based drilling fluids were used to form synthetic muds known as sample A and B respectively. Inference from results shows that the Newtonian model underestimated the pump pressure by 78.27% for sample A and 82.961% by for sample B. While the Bingham plastic model overestimated the total pump pressure by 100.70% for sample A and 48.17% for sample B. Three different power law rheological model approaches were used to obtain the flow behavior index and consistency factor of the drilling fluids. For the power law rheological model approaches, an underestimation error of 23.5743% was encountered for the Formular method for sample A while the proposed consistency index averaging method reduces the error to 14.9306%. The Graphical method showed a reasonable degree of accuracy with underestimation error of 5.6435%. Sample B showed an underestimation error of 47.8234% by using the power law formula method while the Consistency averaging method reduced the error to 20.7508. The graphical method showed an underestimation error of 0.4318%.

Physicochemical and Rheological Properties of Salmon Protein Powders

2006 ◽  
Vol 2 (2) ◽  
Author(s):  
Subramaniam Sathivel ◽  
Peter J Bechtel ◽  
Witoon Prinyawiwatkul
Keyword(s):  
Parallel Plate ◽  
Emulsion Stability ◽  
Nitrogen Solubility ◽  
Loss Modulus ◽  
Flow Behavior ◽  
Power Law Model ◽  
Flow Behavior Index ◽  
K Value ◽  
Viscoelastic Characteristics ◽  
Behavior Index

This study demonstrated feasibility of producing soluble protein powders from pink (PSP) and red (RSP) salmon heads. Differences were observed between physicochemical properties of the two protein powders, including nitrogen solubility, emulsion stability, and fat adsorption capacity. The flow and viscoelastic properties of the emulsions prepared with PSP and RSP were investigated using a parallel plate rheometer. The power law model and the Casson model were used to determine the flow behavior index (n), and consistency index (K) and yield stress. The emulsion containing PSP (PSPE) had a higher K value (8 Pa.s) than that (4.2 Pa.s) of the emulsion containing RSP (RSPE). Both PSPE and RSPE emulsions exhibited pseudoplastic behavior and viscoelastic characteristics. The G’ (an elastic or storage modulus) and G” (a viscous or loss modulus) values for PSPE were higher than RSPE.

Flow Resistance and Mass Transfer in Slow Non-Newtonian Flow Through Multiparticle Systems

1992 ◽  
Vol 59 (2) ◽  
pp. 431-437 ◽  
Author(s):  
M. G. Satish ◽  
J. Zhu
Keyword(s):  
Mass Transfer ◽  
Fluid Flow ◽  
Power Law ◽  
Cell Model ◽  
Flow Behavior ◽  
Solid Sphere ◽  
Power Law Fluid ◽  
Flow Behavior Index ◽  
Flow Through ◽  
Behavior Index

Finite difference solutions for a power-law fluid flow through an assemblage of solid particles at low Reynolds numbers are obtained using both the free-surface cell model and the zero-vorticity cell model. It is shown that, unlike in the case of power-law fluid flow past a single solid sphere, the flow drag decreases with decrease of flow behavior index, and that the degree of this reduction is more significant at low voidage. The results from this study are found to be in good agreement with the approximate solutions at slight pseudoplastic anomaly and the available experimental data. The results are presented in closed form and compare favorably with the variational bounds and the modified Blake-Kozeny equations. Numerical results show that a decrease in the flow behavior index leads to a slight increase in the mass transfer rate for an assemblage of solid spheres, but this increase is found to be small compared with that for a single solid sphere.

Rheological investigations of water-soluble polysaccharides extracted from Moroccan seaweed Cystoseira myriophylloides algae

2020 ◽  
Vol 11 (3-4) ◽  
pp. 49-63
Author(s):  
Soumia Zaim ◽  
Omar Cherkaoui ◽  
Halima Rchid ◽  
Rachid Nmila ◽  
Reddad El Moznine
Keyword(s):  
Rheological Properties ◽  
Power Law ◽  
Flow Behavior ◽  
Viscoelastic Behavior ◽  
Shear Thinning ◽  
Water Soluble ◽  
Flow Behavior Index ◽  
Dynamic Rheological Properties ◽  
Different Temperatures ◽  
Tan Δ

The rheological properties and spectrum infrared of polysaccharides extracted from Cystoseira myriophylloides algae were investigated in the concentrations range from 3 to 9% (w/v) and at different temperatures. Results of rheological characteristics in a steady shear rate showed pseudoplastic properties and the dynamic rheological properties showed a fluid-like viscoelastic behavior. The flow and viscoelastic characteristics of polysaccharides were described using the power-law (the Ostwald model). The values of flow behavior index of the sample were close to unity (0.91) for 3% and it decreased up to 0.71 for 9% revealing the shear-thinning (pseudoplastic) nature of these polysaccharides. Moreover, the consistency coefficient increased non-linearly with concentration and it was described by a power law. The flow behavior as a function of temperature was satisfactorily described using the Arrhenius law and the activation energy values were extracted. It decreased from 15.68 and 17.21 kJ/mol when the concentration increased from 5 to 9% (w/v). Additionally, in dynamic rheological measurements, tan δ > 1 and G″ > G′ reveling a shear-thinning behavior. Finally, the analysis of the FTIR spectra of these polysaccharides showed the presence of uronic acid groups. This behavior would suggest that polysaccharides extracted from Cystoseira myriophylloides could be an interesting additive as thickeners.

Lubrication of a Cylinder on a Plane With a Non-Newtonian Fluid Considering Cavitation

1982 ◽  
Vol 104 (2) ◽  
pp. 168-172 ◽  
Author(s):  
Prawal Sinha ◽  
Chandan Singh
Keyword(s):  
Theoretical Analysis ◽  
Load Capacity ◽  
Flow Behavior ◽  
Rolling Contact ◽  
Maximum Pressure ◽  
Power Law Model ◽  
Flow Behavior Index ◽  
Joint Lubrication ◽  
Human Joint ◽  
Behavior Index

This paper presents a theoretical analysis of lubrication of rolling contact bearings considering cavitation with a non-Newtonian lubricant, obeying the power law model. Piezo-viscous and deformation effects are neglected. The analysis reveals, that as the flow behavior index increases, the load capacity increases and the point of cavitation as well as the point of maximum pressure is shifted towards the center of contact. It is also indicated that the present analysis may be considered as providing an approximation to human joint lubrication problem.

A Comparative Analysis of Mixing Performance of Power-Law Fluid in Cylindrical Microchannels With Sudden Contraction/Expansion

2020 ◽  
Vol 142 (6) ◽  
Author(s):  
A. Banerjee ◽  
A. K. Nayak ◽  
B. Weigand
Keyword(s):  
Pressure Drop ◽  
Power Law ◽  
Flow Behavior ◽  
Geometric Parameters ◽  
Mixing Efficiency ◽  
Flow Behavior Index ◽  
Mixing Performance ◽  
Geometric Configurations ◽  
Wide Range ◽  
Behavior Index

Abstract This paper focuses on the comparative electrokinetic micromixing of non-Newtonian fluid in cylindrical microchannels with surface potential heterogeneity due to sudden constriction/expansion. In numerical simulations, the rheology of the aqueous solution is considered to follow power-law characteristic. Based on the Poisson–Nernst–Planck model, the simulations are performed to investigate the mixing efficiency and pressure drop for constricted and expanded configurations over a wide range of the flow behavior index, potential patch strength, and geometric parameters. The results show that, irrespective of geometric configurations, the mixing efficiency can be improved significantly by increasing the flow behavior index, geometric parameters, and the overpotential patch strength. In addition, it is also revealed that the constricted geometry yields better mixing as compared to the other configuration, but the average pressure drop shows reverse characteristics. Thus, a parametric relationship is tried to be established between mixing efficiency and pressure drop for both these configurations to propose an effective and efficient micromixer, which can produce maximum possible mixing efficiency with minimum pressure drop.

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