Yield Stress Values Research Articles

Implementation of a New Smart-Lubricant Model Using Generalized Newtonian Approach in Soft Elastohydrodynamic Lubrication

Abstract This is an inceptive attempt to replace the classical Bingham fluid model with a continuous double Newtonian power-law-based constitutive equation for smart lubricants like magneto-rheological, electro-rheological, and ferro-fluids. The implementation of Bingham model in hydrodynamic (HD) and elastohydrodynamic (EHD) lubrication analyses is highly challenging and inconvenient due to its inherent discontinuity. Therefore, the present work demonstrates the use of an already existing rheological model with an appropriate set of parameters to describe the flow behavior of smart lubricants in a soft-EHD lubrication algorithm based on the generalized Newtonian approach. The formation of both floating and adherent cores validates the proposed model. An extensive parametric study is also performed to explore the effects of operating speed, load, and slide-to-roll ratio on the soft-EHL characteristics. The results are very promising, showing that it's possible to customize smart lubricants to match specific operating conditions. This is achieved by adjusting the yield stress value accordingly, allowing for the desired variation in lubrication characteristics.

Tensile Yield Strain of Human Cortical Bone from the Femoral Diaphysis Is Constant among Healthy Adults and across the Anatomical Quadrants.

The literature suggests that the yield strain of cortical bone is invariant to its stiffness (elastic modulus) and strength (yield stress). However, data about intra-individual variations, e.g., the influence of different collagen/mineral organisations observed in bone aspects withstanding different habitual loads, are lacking. The hypothesis that the yield strain of human cortical bone tissue, retrieved from femoral diaphyseal quadrants subjected to different habitual loads, is invariant was tested. Four flat dumbbell-shaped specimens were machined from each quadrant of the proximal femoral diaphysis of five adult donors for a total of 80 specimens. Two extensometers attached to the narrow specimen region were used to measure deformation during monotonic tensile testing. The elastic modulus (linear part of the stress-strain curve) and yield strain/stress at a 0.2% offset were obtained. Elastic modulus and yield stress values were, respectively, in the range of 12.2-20.5 GPa and 75.9-136.6 MPa and exhibited a positive linear correlation. All yield strain values were in the narrow range of 0.77-0.87%, regardless of the stiffness and strength of the tissue and the anatomical quadrant. In summary, the results corroborate the hypothesis that tensile yield strain in cortical bone is invariant, irrespective also of the anatomical quadrant. The mean yield strain value found in this study is similar to what was reported by inter-species and evolution studies but slightly higher than previous reports in humans, possibly because of the younger age of our subjects. Further investigations are needed to elucidate a possible dependence of yield strain on age.

The rheological behavior characterization and prediction of cement concrete containing magnetite (Fe3O4) and/or carbon fiber

The effect of magnetite and carbon fiber (CF) on the rheological properties of concrete was investigated to reflect and affect its engineering performance development. The rheological parameters of concrete were measured. Next, a prediction model was established to predict the change tendency in the rheological properties of concrete. Then, the correlation between rheological and mechanical properties was investigated to explore the mechanism of rheological behavior on its engineering performance. The results showed that magnetite and CF had a significant effect on the rheological behavior of concrete. When the magnetite and CF contents were 50 % and 0.5 wt%, the yield stress and plastic viscosity of concrete increased by 210.77 % and 35.88 %, respectively, compared to the control group. The physical properties of the materials, their interaction with the cement matrix and their effect on the volume fraction of the concrete system are the main factors affecting the rheological properties of concrete. Meanwhile, the prediction model established by using the nonlinear surface fitting function could effectively predict the influence of materials on the rheological behavior of concrete. The R2 between the predicted and measured values of yield stress could be up to 0.99. However, under the condition of large magnetite and CF content, the aggregation effect of the materials had a certain influence on the plastic viscosity of the concrete, resulting in a certain deviation between the predicted and measured values, but the R2 could still be up to 0.89. It indicated that the prediction model had favorable reliability and accuracy. A strong correlation existed between the rheological parameters and mechanical strength of concrete. The effect of magnetite and CF on rheological properties of concrete promoted the internal microstructure characteristics optimization of concrete to affect its mechanical properties.

The Effects of Organically Modified Lithium Magnesium Silicate on the Rheological Properties of Water-Based Drilling Fluids.

To address the problem of insufficient temperature and salt resistance of existing polymer viscosity enhancers, we designed an organic-inorganic hybrid composite as a viscosity enhancer for water-based drilling fluids, named LAZ, and it was prepared by combining a water-soluble monomer and lithium magnesium silicate (LMS) using an intercalation polymerization method. The composite LAZ was characterized using Fourier transform infrared spectroscopy, transformed target X-ray diffractometry, scanning electron microscopy, and thermogravimetric analysis. The rheological properties of the composite LAZ were evaluated. The composite LAZ was used as a water-based drilling fluid viscosity enhancer, and the temperature and salt resistance of the drilling fluid were evaluated. The results showed that the composite LAZ presented a complex reticulation structure in an aqueous solution. This reticulation structure intertwined with each other exhibited viscosity-enhancing properties, which can enhance the suspension properties of water-based drilling fluids. The aqueous solution of the composite LAZ has shear dilution properties. As shear rate increases, shear stress becomes larger. The yield stress value of the aqueous solution increases as the composite LAZ's concentration increases. The aqueous solution of the composite LAZ exhibits strong elastic characteristics with weak gel properties. The addition of the composite LAZ to 4% sodium bentonite-based slurry significantly increased the apparent viscosity and dynamic shear of the drilling fluid. The drilling fluids containing the composite LAZ had good temperature resistance at 150 °C and below. The rheological properties of brine drilling fluids containing the composite LAZ changed slightly before and after high-temperature aging at 150 °C.

Enhancing Cement Paste Properties with Biochar: Mechanical and Rheological Insights

Biochar, the solid sub-product of biomass pyrolysis, is widely considered an effective water retention material thanks to its porous microstructure and high specific surface area. This study investigates the possibility of improving both mechanical and rheological properties of cement pastes on a micro-scale. The results show that using biochar as a reinforcement at low percentages (1% to 5% by weight of cement) results in an increase in compressive strength of 13% and the flexural strength of 30%. A high fracture energy was demonstrated by the tortuous crack path of the sample at an early age of curing. A preliminary study on the rheological properties has indicated that the yield stress value is in line with that of self-compacting concrete.

An experimental investigation and flow-system simulation about the influencing of silica–magnesium oxide nano-mixture on enhancing the rheological properties of Iraqi crude oil

This study aims to investigate the effects of introducing a 50/50 mixture of silica and magnesium oxide nanoparticles (SNP + MgONP) to the viscosity of Al-Ahdab crude oil (Iraq) at varied concentrations and temperatures. It is observed that the viscosity value drops from 38.49 to 7.8 cP. The highest degree of viscosity reduction is measured to be 56.91% at the maximum temperature of 50 °C and the greatest concentration of 0.4 wt% SM4. The Bingham model can be used to classify the behavior of the crude oil before the Nano-mixture is added. The liquid behavior grew closer to Newtonian behavior once the Nano-mixture was added. Along with a rise in plastic and effective viscosity values, the yield stress value decreases as the concentration of the Nano-mixture increases. The numerical data demonstrate that when the volume proportion of nanoparticles increases, the pressure distribution decreases. Furthermore, as the nanoparticle volume fraction increases, the drag decrease would also increase. SM4 obtains a maximum drag reduction of 53.17%. It is discovered that the sample SM4 has a maximum flow rate increase of 2.408%. Because they reduce the viscosity of crude oil, nanoparticles also reduce the friction factor ratio.

Effect of Silica Fume Utilization on Structural Build-Up, Mechanical and Dimensional Stability Performance of Fiber-Reinforced 3D Printable Concrete.

It is known that 3D printable concrete mixtures can be costly because they contain high dosages of binder and that the drying-shrinkage performance may be adversely affected. Mineral additives and fibers are generally used to control these negative aspects. In this study, the use of silica fume, a natural viscosity modifying admixture, was investigated to improve the rheological and thixotropic behavior of 3D printable concrete mixtures reinforced with polypropylene fiber (FR-3DPC). The effect of increasing the silica fume utilization ratio in FR-3DPC on the compressive strength (CS), flexural strength (FS), and drying-shrinkage (DS) performance of the mixtures was also examined. A total of five FR-3DPC mixtures were produced using silica fume at the rate of 3, 6, 9, and 12% of the cement weight, in addition to the control mixture without silica fume. As a result of the tests, the dynamic yield stress value decreased with the addition of 3% silica fume to the control mixture. However, it was found that the dynamic yield stress and apparent viscosity values of the mixtures increased with the addition of 6, 9, and 12% silica fume. With the increase in the use of silica fume, the CS values of the mixtures were generally affected positively, while the FS and DS behavior were affected negatively.

Creep and recovery in dense suspensions of smooth and rough colloids

We report the effect of particle surface roughness on creep deformation and subsequent strain recovery in dense colloidal suspensions. The suspensions are composed of hard-spherelike poly(methyl methacrylate) smooth (S) and rough (R) colloids with particle volume fractions ϕS = 0.64 ± 0.01 and ϕR = 0.56 ± 0.01, corresponding to a distance of 3.0% and 3.4% based on their jamming volume fractions (ϕJS=0.66±0.01, ϕJR=0.58±0.01). The suspensions are subject to a range of shear stresses (0.01–0.07 Pa) above and below the yield stress values of the two suspensions (σyS=0.035Pa, σyR=0.02Pa). During creep, suspensions of rough colloids exhibit four to five times higher strain deformation compared to smooth colloids, irrespective of the applied stress. The interlocking of surface asperities in rough colloids is likely to generate a heterogeneous microstructure, favoring dynamic particle activity and percolation of strain heterogeneities, therefore resulting in higher magnitude of strain deformation and an earlier onset of steady flow. Strain recovery after the cessation of stress reveals a nonmonotonic recoverable strain for rough colloids, where the peak recoverable strain is observed near the yield stress, followed by a steep decline with increasing stress. This type of response suggests that frictional constraints between geometrically frustrated interlocking contacts can serve as particle bonds capable of higher elastic recovery but only near the yield stress. Understanding how particle roughness affects macroscopic creep and recovery is useful in designing yield stress fluids for additive manufacturing and product formulations.

Analisis Perbandingan Sifat Mekanik Sambungan Kampuh V Terhadap Kampuh U Hasil Pengelasan SMAW Menggunakan Posisi 3G pada Baja St 37

Selection of the type of support that is appropriate to the load will affect the mechanical and physical properties. Using a good type of support and in accordance with welding procedures can have an influence on the welding results (weldability properties). The comparison of the mechanical properties of V-joints to U-joints is that the maximum tensile stress value between V-joints and U-joints is a maximum of 477.17 N/mm2, while the maximum tensile stress value of V-joints is 453.12 N/mm2. The strain value between the V seam connection and the U seam connection is 20%, while the strain value for the V seam connection is 30%. The yield stress value between the V seam joint and the U seam joint is found in the U seam joint with a yield stress value of 356.05 N/mm2, while the yield stress value for the V seam joint is 337.6 N/mm2. The modulus of elasticity value between the V seam connection and the U seam connection is 2,518.09 N/mm2, while the modulus of elasticity value for the V seam connection is 1,529.43 N/mm2.

Enhancement of γ/γ’ Microstructured Cobalt Superalloys Produced from Atomized Powder by Creating a Harmonic Structure

A material’s properties must be continuously improved to meet the demands of extreme conditions in high-temperature applications. It is demonstrated that γ-γ’ Co-based superalloys could surpass the yield stress of Ni-based superalloys at high temperature due to the γ-γ’ structure. The powders were subjected to a harmonic modification in order to refine the grain structure on the surface and to activate the sintering process. This study examines how harmonic structure affects microstructure and mechanical properties at high temperatures. Spark Plasma Sintering (SPS) was used for consolidation to maintain the ultrafine grain size microstructure of the powder. Compression tests were conducted from room temperature (RT) to 750 °C to assess the mechanical properties of the material. Yield stress values obtained from harmonic structures are four times higher than those obtained from cast alloys.

Inelastic Deformation and Local Slenderness Requirements for Rectangular HSS Braces

Rectangular hollow structural sections (HSS) are commonly used as bracing in concentrically braced frames (CBFs) designed and detailed for seismic design requirements. As the primary yielding component in CBFs, braces are expected to sustain large inelastic axial deformation during earthquake loading. It is well known that their deformation capacity depends on the width-to-thickness ratio (local slenderness). Until 2013, HSS sections were produced to meet ASTM standard A500/A500M; after 2013, the ASTM 1085 specification was implemented, and since that time, HSS sections have also been produced to meet ASTM A1085/A1085M standards. Where the ASTM A500/A500M specification requires minimum yield and tensile stress values as well as a minimum elongation and tolerances on the wall thickness, the ASTM A1085/A1085M specification also requires a minimum Charpy V-notch (CVN) toughness, a maximum yield stress of the steel, and tighter tolerances on the wall thickness and radius of curvature of the corner. These requirements offer a more reliable brace for CBFs in seismic regions. Yet there has been limited research investigating the cyclic axial response of these members. A research study was undertaken to investigate the response of ASTM A1085/A1085M tubes using the response of ASTM A500C tubes as their reference. Forty-one brace specimens were tested under cyclic inelastic axial deformation. Comparison of the data shows that most of the ASTM A500/A500 M Grade C and ASTM A1085/1085M braces meet the respective requirements of their respective ASTM standard and that the differences between the performance of ASTM A500/A500M and ASTM A1085/1085M braces are not dramatic. In addition, the study investigated the impact of width-to-thickness ratio, global slenderness, and displacement history on the response of the braces. The data show that the current AISC 341-22 high-ductility slenderness limit for special concentrically braced frame (SCBF) braces is slightly conservative. However, the data suggest that the moderate ductility slenderness limit used for ordinary concentrically braced frame (OCBF) braces is significantly more conservative than required for consistent seismic safety. Further research is required to determine appropriate limits; this paper provides some initial recommendations based on this dataset.

Visualizing flow dynamics and restart of Carbopol gel solutions in tube and parallel-plates geometries with wall slip.

The present study examines the impact of slip in Carbopol solutions during the restart flow in pipelines utilizing in situ visualization techniques. Rheological tests were conducted using smooth and hatched parallel plate geometries to obtain the rheological characteristics of the solutions. The behavior of the solutions in the creep tests is compared with those in the experimental unit. Three flow regimes were identified through rheological and experimental setup tests: non-flow, slip, and yielded. The slip regime allowed the establishment of a slip static yield stress value, indicating significant deformation states, and a restart pressure decrease of about 61% when compared to the static yield stress. The flow dynamics under the wall slip effect is captured by velocity profiles, velocity contour maps and velocity gradient. Transient correlations of the scaling law type were determined, with wall slip in proportion to the velocity gradient and wall shear stress. Additionally, the concentration of viscoplastic material in the solution increased the scaling law index. This research seeks to provide valuable findings by quantifying the effects of apparent wall slip through in situ measurements. Such insights are crucial for designing and managing pipeline transport systems that handle yield stress fluids, applicable across various industries including cosmetics, food processing, and the production of waxy oils.

Testes de controle de qualidade de materiais frescos à base de cimento para impressão 3D

Abstract Three-dimensional concrete printing (3DCP) has emerged as a promising solution for the modernization of the construction sector. Additionally, design optimization allows for material reduction, promoting sustainable construction. Despite these advancements, there is still no standard for the assessment of the fresh state and quality control of 3DCP. This work discusses the results of quality control tests for fresh 3DCP. Specifically, seven samples with different mix designs were produced and subjected to rotational rheometry, slug tests, flow table tests, and buildability tests (i.e., the height supported prior to collapse). The results showed that the yield stress obtained from rheometry and the slug test did not match but fell within the same order of magnitude. The yield stress values obtained from rheometry were the closest to the gravity-induced stress in the buildability test. Regarding buildability prediction, the slug test exhibited the strongest correlation with the number of layers supported in buildability (R2 = 0.92); rotational rheometry also demonstrated a good correlation with that parameter (R2 = 0.80). In contrast, the results of the flow table test neither correlated with the yield stress obtained from any other tests nor proved efficient in predicting buildability. Finally, the paper presented a discussion on testing and printing challenges.

Showing the role of weakly-bound particles flocculation in the reversibility of thixotropic behavior for fresh cement paste

The thixotropic behavior of fresh cement-based materials has been found to be derived from the reversible breakage and agglomeration of flocculated cement grains. The existence of thixotropy can lead to significant variations in shear stress and apparent viscosity under the same shear rate, which brings great challenges for measuring rheological performance. This paper highlights the difference between strong and weak particles flocculation for the first time, and then reveals the intrinsic interactions of various thixotropic and rheological parameters. The thixotropic behavior and dynamic yield stress were evaluated for cement paste samples with different resting time and temperature conditions. It was found that the longer resting time, the higher temperature, and the larger solid volume fraction increased the difficulties for both the structural breakdown and the subsequent structural re-buildup processes, indicating the lower reversibility of thixotropic behavior; These factors also led to higher dynamic yield stress, more amount of strongly-bound flocs, but less weakly bound flocs. After removal of shear force, the microstructure reconstruction ability of fresh cement paste was highly correlated to the recovery of dispersed weak flocs, but with little regard to strong flocs. The dynamic yield stress value could be dependent on the breakage degree of flocculation, while the prolonged duration of last several steps in the descending portion of the rheometric procedure enhanced the dynamic yield stress due to structural re-buildup. The results will provide new in-depth insights into the roles of strong and weak flocs in the reversible thixotropic behavior of fresh cement-based materials.

Pressure-based analysis of rheological equilibrium distances of pumped self-consolidating concrete (SCC)

The influence of pumping on the rheological properties of self-consolidating concrete (SCC) is widely recognized, but there is still limited understanding of its behavior within the pipeline. In this study, we propose a novel approach using equilibrium distances to investigate the evolution of rheological properties along the pipeline. Full-scale horizontal pumping circuits spanning 328 m were established to assess the axial development of SCC's rheological properties. Thirteen mixtures, with water-to-cement (w/c) ratios ranging from 0.22 to 0.27, were pumped at discharge rates varying from 5.77 to 12.69 L/s. Our findings show that for pumping setups and material studied, both the w/c ratio of SCC and the discharge rate significantly affected the influence of rheological equilibrium distances on pressure loss gradient changes. In all tested samples, viscosity values required the entire length of the pipeline to reach post-pumping levels, while yield stress values rapidly achieved their fully developed state upon entering the pipeline. Importantly, the predicted pressure loss displayed a strong correlation with experimental measurements, with an accuracy of 89.42% across all tested mixtures. Our predictive model showed an average improvement of 4.6% in accuracy compared to the linear approach, with the most significant enhancement observed in samples with higher w/c ratios. This research sheds new light on the behavior of SCC during pumping and provides valuable insights for optimizing the pumping process.

Tailoring the rheological properties of biosynthesized Copper oxide nanoparticles decorated Carboxymethyl cellulose hydrogels for biomedical applications

Nanoparticle-decorated hydrogels have seized substantial momentum in recent years, exclusively in biomedical research. In this investigation, Copper oxide nanoparticles decorated carboxymethyl cellulose hydrogels were prepared in an eco-friendly approach without using toxic cross-linkers. Initially, Copper oxide nanoparticles were prepared by biosynthesis approach to diminish the harmful effects of chemicals and to improve the biological activities using the leaf extract of Justicia adhatoda. The prepared nanoparticles were incorporated into the Carboxymethyl solution and carbopol to form a hydrogel by non-covalent interactions. X-ray diffraction analysis of CuO nanoparticles revealed a monoclinic crystalline structure without impurity. Rheological investigation of the pure hydrogel and CuO-decorated hydrogels revealed that CuO contributed to the enhancement of the hydrogel's mechanical performance. All the hydrogels demonstrated shear thinning behavior and better flow behavior index with the addition of CuO nanoparticles. The yield stress of the hydrogels was improved and found to be in the range of 61–79 Pa, which matches the ideal yield stress values in transdermal drug delivery. Storage moduli of hydrogels as a function of frequency was doubled (14–47.5 Pa), endorsing the involvement of CuO nanoparticles in crosslinking the polymeric matrix. Temperature and time sweep measurements revealed that the stability of the hydrogels also improved with the addition of CuO nanoparticles. The antibacterial activity of the hydrogels was evaluated using biofilm inhibition and showed better inhibition of 70 ± 0.5%, 75 ± 0.9%, 86 ± 0.8%, and 83 ± 0.8% against Escherichia coli, Klebsiella pneumonia, Staphylococcus aureus, and Enterococcus faecalis, respectively with increased concentration of CuO nanoparticles. The cell viability of the CuO-decorated hydrogels against MCF-7 and A431 was found to be 39% and 42%, respectively. Therefore, the eco-friendly biosynthesized CuO nanoparticles decorated hydrogels with improved mechanical properties can be employed in injectable and transdermal drug delivery systems.

Adhesive and rheological properties of fresh mortar with manufactured sand as replacement of river sand

This paper investigates the adhesive properties of fresh mortar with manufactured sand (Msand) as replacement of river sand (Rsand). Adhesive properties were evaluated by normal force evolution curves from the tack test. Both static and dynamic yield stress were measured to elaborate the influence of Msand replacing Rsand on the adhesive properties. Results indicate that Msand increases the adhesive force, critical displacement, stiffness, and adhesive failure energy whereas shortens the debonding duration. Replacement of Rsand by Msand gradually promotes the transition of failure mode from cohesive rupture to adhesive rupture. The adhesive force of mixtures showing cohesive rupture is highly related to their static yield stress values.

Structural Integrity of Turbine Stator Blades Using Different Super Alloys with Internal Cooling at Fluid Temperature Range of 600 K – 700 K

The importance of turbines in power generation cannot be overstated. While the failure in stationary plants can lead to downtime and high repair costs, its failure in mobile plants like the jet engines can be catastrophic with attendant loss of lives. Hence, by all possible means, the prevention of turbine failure is a necessity, and a very good means of doing this is with the use of super-alloys. Super-alloys are tailored to withstand the demands of turbine operations especially stress and elevated temperature and pressure. The blades are thus, manufactured from super-alloys, and of prominence are the Nickel-based super-alloys. The performance of five different super-alloys: (DS) GTD 111, Ti-6Al-4V, Inconel 718, CMSX-4, and Nimonic 80A was simulated using COMSOL MultiPhysics 5.5 at cooling air temperature range of 600 K – 700 K. The mode of cooling employed in the study is only internal cooling. With the developed stress percentage of the yield stress value and the stator blade displacement at the operating conditions as the criteria of performance, super-alloy Ti-6Al-4V faired as the best material for the stator blade.

Laminar planar hydraulic jump during free surface flow of Bingham plastic liquid

The hydrodynamics of laminar planar hydraulic jump during free surface flow of Bingham plastic liquid is investigated through numerical simulation and shallow flow analysis, both validated against experimental results. The singularity of Bingham plastic model at the yield surface is addressed by adopting the Bingham plastic Papanastasiou regularized model with the value of regularization parameter as 1000 s in order to mimic ideal BP flow. The study reveals that an increase in both yield stress and plastic viscosity creates a jump closer to the inlet with a higher film thickness and jump strength. Interestingly, a higher Froude number shifts jump towards channel exit with increased strength while a higher Reynolds number forms a jump of lower strength closer to exit. The jump types noted from simulations are presented as phase diagrams in terms of inlet Reynolds and inlet Froude number for different yield stress values.

A method for determining the rheological properties of viscoplastic fluids using a rectangular die

This study introduces a method for determining the rheological parameters of viscoplastic fluids with the use of rectangular dies. The relationship between the wall shear rate and the wall shear stress is investigated for the Casson, Herschel-Bulkley, and Robertson-Stiff rheological models, using two geometric constants for non-circular dies with a regular cross-section. Then, the rheological behavior and parameters of a collagen material were examined by an analytical method and by the proposed approximate method, using experimental data obtained by a slit viscometer and a rectangular die. The yield stress value of the collagen was determined employing the pressure relaxation method. The values were 2940 (±209) Pa from the slit viscometer and 3100 Pa (± 200) Pa from the rectangular die. The rheological parameters of collagen were then obtained using the analytical method and the proposed approximate methods for Casson, Herschel-Bulkley, and Robertson-Stiff rheological models. It was shown that the wall shear rate and the wall shear stress values of the analytical method and the proposed method are in good agreement. It was found that the Herschel-Bulkley and Robertson-Stiff models successfully fitted the wall shear rate-wall shear stress curves with a coefficient of determination equal to or greater than 0.97, and the evaluated consistency values were 165 (±71) Pa.sn for the Herschel-Bulkley model and 947 (±225) Pa.sn for the Robertson-Stiff model, and the flow index values were found to be 0.50 (±0.06) for the Herschel-Bulkley model and 0.32 (±0.03) for the Robertson-Stiff model. However, it was shown that the Casson model is not suitable for describing the rheological characteristic of collagen material. Experimentally obtained parameters for the Herschel-Bulkley model were validated with the use of simulations, and it was found that the numerically and experimentally evaluated results showed good agreement. The maximum deviation was found to be less than 12%.