Effect Of Friction Factor Research Articles

Effects of friction factor on mechanical performance of the AA5182 clinched joint

Effects of friction factor on mechanical performance of the AA5182 clinched joint

An experimental analysis on nanoparticles role in drilling fluids

The study around nanotechnology has increased in the last decade or so, with rise in applications in many industries. There are now many nanotechnology-based products available like in healthcare, defense, coating industries etc. It has seen rise in usage in oil and gas industry as well. Application of nano particles in water based muds results in reduction of fluid loss and hence increases the wellbore stability and drilling efficiency. In this study, we have examined the fluid loss on water-based mud by adding graphene nanoparticles as additive and estimated the optimum value of nanoparticle composition for having less fluid loss. The results of experimental analysis for filtration loss from water-based mud with addition of graphite nanoparticles was studied and effect of friction factor was analyzed. The nanoparticles concentration added in fluid ranges from 1 to 5 lb/bbl and the size of the particles was observed to be 30–80 nm. Variation of fluid loss volume and friction coefficient under different nanoparticle composition was established.

Prediction of heat transfer enhancement of delta-wing tape inserts using artificial neural network

This work adopts the artificial neural network (ANN) for predicting the efficiency of a double-pipe heat exchanger which employs T-W tape inserts with different wing-width ratios (w/W) of 0.31, 0.47, and 0.63. The effects of friction factor (f), Nusselt number (Nu), and thermal performance (η) are predicted using the established multi-layer ANN. Different scenarios are examined using two parameters as inputs to the ANN: Reynolds number (Re) and w/W. The results prove that the developed ANN model is able to accurately predict the experimental data. The obtained mean square error has a value of less than 0.7 as compared to the experimental values. Furthermore, the proposed ANN-based approach is also effective to predict the thermal parameters, with the least variance and high precision. In addition, a multiple linear regression is employed to check the efficiency of the proposed model from which it is demonstrated that the suggested neural network method provides useful guidance for accurately predicting the thermal parameters with the least variance. The configuration of 2–10-1 is found to be the best for the current model, with a mean absolute error of 0.546896.

Experimental studies of helical coils in laminar regime for mechanically agitated vessel

The aim of this experimental study is to determine the heat transfer coefficients in laminar regime of mechanically agitated vessel for Newtonian (water) and non-Newtonian fluids, i.e. CMC (carboxy methyl cellulose) solutions in mechanically agitated vessel. It is found that Dean number and Prandtl number play an important role with Nusselt number while determining heat transfer coefficients. Modified Wilson plot is used to find heat transfer. The effect of friction factor on Reynolds number is also studied. The laminar flow heat transfer results have been successfully correlated in the following form with 15% standard deviation and this equation is suitable for the correlation for both Newtonian and non-Newtonian fluids to find heat transfer coefficients in helical coils in mechanically agitated stirred vessel.

A forming load analysis for extrusion process of AZ31 magnesium

Abstract The effect of extrusion parameters on the extrusion load for AZ31 magnesium alloy was investigated with the support of numerical methods. With this regard, the process temperature, extrusion ratio, friction factor and punch velocity were selected as main parameters for the experiments. Besides, the experimental results were analyzed by using the finite element method (FEM) and artificial neural network (ANN) method to build a numerical model for predicting the forming load. All the experimental and numerical results were compared to each other and it was concluded from the results that the effect of friction factor on the extrusion load is more dominant at lower extrusion temperature for all given extrusion ratios and punch velocities. Besides this, higher extrusion ratios require higher process temperatures to obtain the lower extrusion load. Also, it was observed that the increase in the extrusion speed causes a significant increase in the forming load for all extrusion ratios and extrusion temperatures.

Friction factor, Load and Displacement Studies of AA6063 in forward Extrusion process with Equal Channel Angular Pressing (ECAP) Preprocess

Abstract Friction between the die and work piece plays a major role in metal forming process. The Effect of Friction factor, Load and Displacement were studied and analyzed in forward extrusion of AA6063. The Effect of grain size on friction factor during forward extrusion process were also studied and compared. Friction factor values vary much in high area reduction when compared with minimum area reduction . In this work AA6063 Specimens were extruded for a reduction ratio of 4:2. Specimens are also processed through Equal Channel Angular pressing (ECAP) process before extrusion and results are compared without ECAP Processing. Specimens are heated in a muffle furnace with 350°C. Friction factor between the die and work piece was calculated. Extruded specimen, microstructure was also compared with and without ECAP preprocessing.

Simulation and experimental investigation of fluid flow in porous and non-porous solar air heaters

The porous absorber in the solar air heater gives considerable temperature increment which is shown by computational fluid dynamic simulation and verified experimentally. Experimental analysis on porous (wire screen) and non-porous solar air heaters were carried out to study the heat transfer and friction factor characteristics. The analysis encompasses the investigation on effect of mass flow rate on air temperature increment, thermal efficiency and pressure drop across the test section. The heat transfer parameter is established in terms of Colburn (Jh) factor for porous bed solar air heaters. The effect of friction factor on different geometries for a range of operating Reynolds number (194–591) is presented. Two wire screen matrix (WSM) solar air heater WSM-I and WSM-II were investigated which has different diameter, pitch and porosity. Thermal efficiency increased on introducing the packed wire-screen matrix diagonally in the air flow path. The increase in thermal efficiency for WSM-I and WSM-II were found to be 5–17% and 5–20% respectively with the mass flow rate ranging from 0.01 kg/s to 0.055 kg/s. The collector heat removal factor was found to be 0.95 ± 0.021 for wire mesh absorber and 0.72 ± 0.0073 for conventional type. The pressure drop across the length of the duct was studied to be in the range of 15 ± 0.28 Pa to 17 ± 0.28 Pa and 7 ± 0.16 Pa to 11 ± 0.28 Pa for WSM-I and WSM-II respectively and for conventional type it was between 5 ± 0.20 Pa and 10 ± 0.28 Pa.

A loading fractal prediction model developed for dry-friction rough joint surfaces considering elastic–plastic contact

In the microscopic view, the contact between two solid surfaces is reckoned to be the contact among asperities indeed. These asperities loaded which contact with each other are to experience three stages of deformation in succession: elastic deformation, elastic–plastic deformation, and plastic deformation, not the direct transition from elastic deformation to plastic deformation. In addition, these asperities should be distributed on the three-dimensional surface topography, and the corresponding fractal dimension is $$2<D<3$$ . In this study, firstly, based on the fractal theory and Hertz contact theory, the loading fractal model of rough dry-friction joint surfaces is established in consideration of elastic–plastic deformation of asperities and three-dimensional surface topography. Secondly, two important fractal parameters, fractal dimension D and fractal roughness G, can be calculated according to sampled surface topography of 45 steel and power spectrum density function method. Then, the effects of friction factor $$\mu $$ , fractal dimension D, and fractal roughness G on the loading fractal model are analyzed by numerical simulation. Finally, the present model is compared with experimental data and other models, which indicates that their trends are the same. The elastic–plastic loading modeling provides a certain theoretical reference for the accurate solution of contact among rough surfaces.

Experimental and numerical investigation of the cylindrical blade tube inserts effect on the heat transfer enhancement in the horizontal pipe exchangers

In this experimental and numerical study an attempt to enhance the heat transfer rate by cylindrical blade that form turbulence flow inside the exchanger pipe is carried out. The effects of the blade geometry are also examined to investigate heat transfer rate in experimented tube inserts. Experiments are performed in different blade spacing (Sy1,2,3 = 101–216–340 mm) and various blade angles (α1,2,3 = 0°–45°–90°). The water flow rate inside the tube is adjusted in three different ranges to approach intended Reynolds numbers (Re1,2,3 = 6000–11,000–17,000). Nusselt number, Reynolds number and effect of friction factor are investigated separately. For all experiments, the increase in Nu number due to used tube inserts is recorded and compared to each other and plain tube in the related profiles. It is concluded that installed tube inserts in the heat exchanger tube, led to a significant increase in Nu number and energy saving. Among different experimented cases, using mean value in various Re numbers, the highest Nusselt number was obtained at Sy1 = 101 mm which was 24% more than that of plain tube. This value was 18.7 and 8.3% for Sy2 = 216 and Sy3 = 340 mm respectively. By this way, according results for friction factor were 0.30, 0.19 and 0.14. The presented study has been simulated by ANSYS Fluent 16 software to analyze flow behavior and heat transfer characteristics.

Experimental Analysis of Heat Transfer and Fluid Flow in Micro-Channel Heat Sink

In this paper heat transfer in single phase through micro-channels was studied. The validation of classical correlations of conventional channels to micro-channels is explored. It is found that classical approach is in good agreement with the experimental results of heat transfer in micro-channels .The material used for micro-channel heat sink (MCHS) is copper, experiments were conducted using water as cooling agent in this study. Micro-channels are made with the help of EDM machine on the upper surface of MCHS. Variation of heat transfer rates, effect of friction factor, effect of pressure drop and variation in temperature distribution is investigated in this study. It is observed in the study that with decrease in velocity flow friction also decreases.

Effects of friction factors on flat bottom self-pierce riveting joints of AZ31 magnesium alloy

Flat bottom self-pierce riveting is a novel metal sheet joining process because it does not need mold design of self-pierce riveting. Joints have flat bottom and high strength, so that flat bottom self-pierce riveting has wide development prospects. With the help of the DEFORM-2D software, this paper studied the effects of friction factors between AZ31 magnesium alloy sheets were studied, and then special simulations were carried out to investigate their effects on joints. The analysis indicates that the appropriate friction factor among blank holder, rivet, sheets and bottom plate is 0.1–0.5 and the friction factors have obvious effects on the quality of joints. The final results may provide the further research with essential guidance.

Experimental and Simulation of Friction Effects in an Open-Die Microforging/Extrusion Process

Friction effects during a progressive microforming process for production of micropins of various diameters were experimentally investigated and were analytically modeled, using a hybrid friction model. The response surface method and ANOVA analysis were used to generalize the findings for various pin diameters. Besides, it was shown that to get an accurate result in simulation, the friction model must be considered locally instead of a global friction model for the whole process. The effect of friction factor on the final micropart dimensions (the effect on the instantaneous location of the neutral plane) and the forming pressure were investigated. The results showed a reduction in the friction factor as die diameter increased. Following that, the optimum frictional condition to obtain the highest micropart aspect ratio was defined as the maximum friction on the interface between the die upper surface and the punch surface, together with a minimum friction inside the die orifice.

Finite Element Analysis for Gear Contact Based on UG and ABAQUS

According to the cutting theory of involute tooth profile, established an exact three-dimensional parametric model by UG. Used ABAQUS to crate finite element model for gear meshing. After simulated the meshing process, discussed the periodicity of the tooth surface contact stress. Based on the result of finite element analysis, made a comparison of the maximum contact stress between finite element solution and Hertz theoretical solution, analyzed the contact stress distribution on tooth width, and researched the effect of friction factor on contact stress. All that provided some theoretical basis for gear contact strength design.

Finite element simulation on press forging of magnesium alloy AZ31 sheets

Press forging of rectangular box of magnesium alloy AZ31 sheets was investigated at elevated temperatures. The characteristics of metal flow were analyzed on the basis of finite element method(FEM) and experiments. Effects of friction factor and sidewall thickness on metal flow and boss forming were investigated by FEM. The results indicate that the bosses and the sidewall of the rectangular box are formed unevenly due to the uneven flow of the metal. The increase in friction factor at die/sheet interface improves the metal flow pattern and the efficiency of boss forming, but reduces the sidewall uniformity. Decrease in sidewall thickness enhances boss forming efficiency, whereas the punch load increases in this case. The present work can provide reasonable parameters and design guideline for the practical press forging process of magnesium alloy sheets.

Effect of friction factor on barrelling in elliptical shaped billets during cold upset forging

This work deals with the effect of friction factor of different lubricants on barrelling in elliptical shaped billets during cold upset forging. Experiments were carried out to generate data on cold upset forging of commercially pure aluminium solid of elliptical billets with different lubricants applied on both sides in order to evaluate the effects of friction factor on the forming behavior of barrelling phenomenon under plane stress state condition. The radius of curvature of both major and minor bulge measured conformed to the calculated one using experimental data and the calculations were made with the assumption that the curvature of the bulge followed the form of a circular arc. Three different b/a ratios (ratio of minor to major diameter) namely, 0.6, 0.7 and 0.8 and aspect ratio (ratio of height to diameter) of 0.75 were prepared and cold upset forged. The relationship was also established between the various bulge parameters like the hoop strain, the axial strain, the new geometric shape factor, the stress ratio parameters, the major and minor radius of curvature of the bulge and the friction factor ‘m’ of different lubricants.

Comparisons of rotordynamic coefficients in stepped labyrinth seals by using Colebrook-White friction factor model

The objective of this work is to observe the effects of friction factors for the stepped labyrinth seals. The gas flow through the seals creates net pressure and shear forces acting on the rotor. It is necessary to predict these forces for reliably operating turbomachinery. So we investigated the effect of shear forces on the calculation of rotordynamic coefficients by comparing the results in the case shear forces are considered and in the case they are neglected. We also compared our results, obtained with the Colebrook–White friction factor model, with some reference experimental and computational results.

Deformation and densification laws of powder cold forging

The deformation and densification laws of preform upsetting and closed-die forging were researched based on experimental results of cold forging of deoxidized Fe powder sintering porous material under different initial conditions such as friction factor, ratio between height and diameter and relative density. The fracture limit criterion for powder cold-forging upsetting and the limit strain curve were achieved. The effect of friction factor, ratio between height and diameter and relative density on fracture strain limitation was emphatically analyzed. The limit process parameter curves for the deformation of upsetting were also confirmed. Laws of deformation, densification and density distribution for closed-die forging of powder perform during cold-forging were further analyzed and discussed with the help of experimental phase analysis. As a result, this experiment established theoretical foundations for the design of preform and die as well as optimization of technological process parameters.

Deformation inhomogeneity in flattened copper wire

The deformation inhomogeneity in flattened wire produced by the wire flat rolling process is studied. Utilizing the combined Finite and Slab Element Method (FSEM), the effective strain fields in the flattened wire are calculated at different reductions in height and frictional conditions and compared with experiment. The calculated and experimental results exhibit that the deformation is inhomogeneous and macroscopic shear bands are appeared in the cross section of flattened wire. Using the results of the analysis, it is shown that the deformation inhomogeneity, introduced by an Inhomogeneity Factor (IF), is different on the x-axis and y-axis in the cross section of the flattened wire. By decreasing the reduction in height of wire and increasing the friction factor, the deformation inhomogeneity is increased and the effect of friction factor is more pronounced at large reduction in height. The variation in IF with the reduction in height is presented by a fourth order polynomial.

A Study on Rotating Compression Forming of Ring Based on the Upper Bound Method

In this paper, an upper bound approach of rotating compression forming of ring is established. Using the upper bound approach, the effects of friction factor, reduction, aspect ratio etc upon compression force, radius of neutral surface, internal radius, spiral lead etc are investigated systematically. The experiment of rotating compression forming of ring made of aluminum alloy A6061 was carried out. Comparisons between the analytical results and the experiment are used to verify the validity of present upper bound approach. The analytical results are in good agreement with the experiment.

A comparison of orthogonal cutting data from experiments with three different finite element models

The aim of this study is to compare various simulation models of orthogonal cutting process with each other as well as with the results of various experiments. Commercial implicit finite element codes MSC.Marc, Deform2D and the explicit code Thirdwave AdvantEdge have been used. In simulations, a rigid tool is advanced incrementally into the deformable workpiece which is remeshed whenever needed. In simulations with MSC.Marc and Thirdwave AdvantEdge, there is no separation criterion defined since chip formation is assumed to be due to plastic flow, therefore, the chip is formed by continuously remeshing the workpiece. However, in simulations with Deform2D, the Cockroft–Latham damage criterion is used and elements, which exceed the predefined damage value, are erased via remeshing. Besides this different modeling of separation, the three codes also apply different friction models and material data extrapolation schemes. Estimated cutting and thrust forces, shear angles, chip thicknesses and contact lengths on the rake face by three codes are compared with experiments performed in this study and with experimental results supplied in literature. In addition, effects of friction factor, different remeshing criteria, and threshold tool penetration value on the results are examined. As a result, it has been found that although individual parameters may match with experimental results, all models failed to achieve a satisfactory correlation with all measured process parameters. It is suggested that this is due to the poor modeling of separation.