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1
Content available Flow features of thermophoretic MHD viscous fluid flow past a converging channel with heat source and chemical reaction
Kalita B. K., Choudhury R.
International Journal of Applied Mechanics and Engineering
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2021
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Vol. 26, no. 3
72--83
EN
A boundary layer flow of an electrically conducting viscous fluid past a converging channel in the presence of thermophoresis, heat source, chemical reaction, viscous dissipation and simultaneous heat and mass transfer characteristics is studied in the paper. An external magnetic field of uniform strength is applied transversely to the channel. The similarity solution has been used to transform the partial differential equations that represent the problem into a boundary value problem of coupled ordinary differential equations, which in turn are solved numerically using MATLAB’s built in solver bvp4c. Numerical computations are carried out to solve the problem and graphical illustrations are made to get the physical insight of the same. The convergent channel flow problem of an incompressible electrically conducting viscous fluid in the presence of a magnetic field has a wide range of applicability in different areas of engineering, specially in industrial metal casting and control of molten metal flow.
2
Content available Effects of pressure work over a semi-infinite vertical oscillating cylinder
Sarojini A., Palani G.
International Journal of Applied Mechanics and Engineering
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2021
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Vol. 26, no. 1
215--225
EN
An arithmetical methodology is used to study natural convection with properties of pressure work over a semi-infinite vertical oscillating cylinder. The governing partial differential equations are set up and the resulting equations are changed into a non-dimensional form using the proper non-dimensional quantities. The set of non-dimensional partial differential equations is solved arithmetically using a well-organized method known as the Crank-Nicolson method. The velocity, as well as temperature profiles for different values of parameters are studied with the assistance of graphs.
3
Content available Static load test curve analysis based on soil field investigations
Siemaszko P., Meyer Z.
Bulletin of the Polish Academy of Sciences. Technical Sciences
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2019
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Vol. 67, nr 2
329--337
EN
This paper expands the M-K curve theory with examples of the most commonly mentioned pile-soil mechanics behaviours in the literature and their corresponding κ 2 variations. A brief introduction shows the history of the Meyer-Kowalow theory and its basic assumptions. This is followed by the relationship between in situ investigation CPT results, with parameters C1, C2, Ct used to approximate the load-settlement curve according to the M-K theory. The Meyer-Kowalow curve satisfies asymptotic behaviour for small loads, where linear theory applies, and for limit loads, when pile displacement is out of control. Essential in the description are constant parameters C, which refer to the aggregated Winklers modulus, Ngr limit loads and k, which is crucial for static load test results. For this reason, the authors sought to calculate the κ value based upon soil mechanics principles. This article shows methods for checking statistical mathematical calculations, published earlier by Meyer using CPT investigations. It presents real case calculations and directions for future planned research.
4
Content available Skin and toe resistance mobilisation of pile during laboratory static load test
Meyer Z., Żarkiewicz K.
Studia Geotechnica et Mechanica
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2018
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Vol. 40, nr 1
1--5
EN
This article shows the mathematical method to determine the lateral stress on the shaft and toe resistance of pile using the new approach. The method was originally invented by Meyer and Kowalow for the static load test. The approximation curve was used for the estimation of both settlement curve and toe resistance curve of the pile. The load applied at the head of the pile is balanced by the sum of two components: the resistance under the toe of the pile and the skin friction. Therefore, the settlement curve is compilation of two factors: the skin friction curve and the resistance under toe curve. The analysis was based on the verification of the methods using laboratory experiments, that is, static load tests. The results of the research allowed to determine the relationship between parameters of the Meyer-Kowalow curve. On the basis of the relationships, it was possible to determine the skin friction and the toe resistance of the pile. Mathematical analysis of curve parameters allowed to determine the influence of the toe resistance on the settlement.
5
Content available Laboratory research of toe resistance based on static pile load tests in different schemes
Żarkiewicz K.
Civil and Environmental Engineering Reports
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2018
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Vol. 28, no. 1
172--181
EN
Transfer of axial force from the head of a pile to the surrounding soil by skin friction and toe resistance is still uncertain. The results of the static pile load test are usually presented as settlement curve. This curve can be divided into two components: skin friction curve and toe resistance curve according to the settlement. Laboratory research of pile load test was carried out in two schemes: with skin friction and without skin friction. The study proved that the toe resistance with and without skin friction is not the same. Skin friction influence on toe resistance due to settlement. This phenomenon is not usually taken into account, but very often has a significant impact on axially applied load transfer. In the paper results of laboratory pile load tests id, different schemes were presented.
PL
Przekazywanie pionowej siły osiowej przyłożonej w głowicy pala na otaczające podłoże gruntowe jest zagadnieniem wciąż nierozwiązanym i w wielu przypadkach budzącym wiele wątpliwości. Wynik próbnego obciążenia statycznego są zwykle przedstawiane na wykresie w postaci krzywej osiadania pala. Krzywa osiadania może być podzielona na dwie składowe krzywe: krzywą oporu pobocznicy i krzywą oporu podstawy pala w stosunku do osiadania głowicy pala. Badania laboratoryjne próbnych obciążeń statycznych zostały przeprowadzone na palach modelowych, w dwóch schematach obciążenia: z udziałem pobocznicy i bez udziału pobocznicy w przekazywaniu obciążenia przyłożonego w głowicy pala. Wyniki badań wskazują, że opór podstawy pala jest różny w zależności od schematu. W związku z tym istnieje zależność oporu podstawy i pobocznicy pala. W artykule przedstawiono wyniki badań laboratoryjnych wraz z interpretacją.
6
Content available On diffusion of chemically reactive species in a convective flow past an inclined plate with variable surface temperature and variable mass diffusion
Kirubavathi J. D., Palani G.
International Journal of Applied Mechanics and Engineering
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2016
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Vol. 21, no. 4
905--922
EN
A numerical solution of a transient natural convection flow past a semi-infinite inclined plate under the combined buoyancy effects of heat and mass transfer along with chemical reaction is presented herewith. The governing boundary layer equations for the above flow problem for a first order homogeneous chemical reaction are set up and non-dimensionalised. An implicit finite difference method is employed to solve the unsteady, nonlinear, integro and coupled partial differential equation. Numerical results are presented for various parameters occurring in the problem. The unsteady velocity, temperature and concentration profiles, local and average skin friction, Nusselt number and Sherwood number are studied for both a generative and destructive reaction.
7
Content available Convective heat transfer in a micropolar fluid over an unsteady stretching surface
Prasad K. V., Vaidya H., Vajravelu K.
International Journal of Applied Mechanics and Engineering
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2016
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Vol. 21, no. 2
407--422
EN
An unsteady boundary layer free convective flow and heat transfer of a viscous incompressible, microploar fluid over a vertical stretching sheet is investigated. The stretching velocity is assumed to vary linearly with the distance along the sheet. Two equal and opposite forces are impulsively applied along the x-axis so that the sheet is stretched, keeping the origin fixed in the micropolar fluid. The transformed highly non-linear boundary layer equations are solved numerically by an implicit finite difference scheme for the transient, state from the initial to the final steady-state. To validate the numerical method, comparisons are made with the available results in the literature for some special cases and the results are found to be in good agreement. The obtained numerical results are analyzed graphically for the velocity, the microrotation, and the temperature distribution; whereas the skin friction, the couple stress coefficient and the Nusselt number are tabulated for different values of the pertinent parameters. Results exhibit a drag reduction and an increase in the surface heat transfer rate in the micropolar fluid flow compared to the Newtonian fluid flow.
8
Content available The importance of the law of the wall
Mandal B. C., Mazumdar H. P.
International Journal of Applied Mechanics and Engineering
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2015
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Vol. 20, no. 4
857--869
EN
This paper reports some results of turbulent boundary layer computation. The calculation is made assuming that law of the wall is valid throughout the boundary layer. Simple relations are proposed for friction for a smooth pipe and a flat plate at zero incidence. The results are compared with recent measurements. Encouraging results are obtained for both the cases of flows.
9
Content available Heat transfer of viscoelastic fluid flow due to nonlinear stretching sheet with internal heat source
Nandeppanavar M. M., Siddalingappa M. N., Jyoti H.
International Journal of Applied Mechanics and Engineering
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2013
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Vol. 18, no. 3
739--760
EN
In the present paper, a viscoelastic boundary layer flow and heat transfer over an exponentially stretching continuous sheet in the presence of a heat source/sink has been examined. Loss of energy due to viscous dissipation of the non-Newtonian fluid has been taken into account in this study. Approximate analytical local similar solutions of the highly non-linear momentum equation are obtained for velocity distribution by transforming the equation into Riccati-type and then solving this sequentially. Accuracy of the zero-order analytical solutions for the stream function and velocity are verified by numerical solutions obtained by employing the Runge-Kutta fourth order method involving shooting. Similarity solutions of the temperature equation for non-isothermal boundary conditions are obtained in the form of confluent hypergeometric functions. The effect of various physical parameters on the local skin-friction coefficient and heat transfer characteristics are discussed in detail. It is seen that the rate of heat transfer from the stretching sheet to the fluid can be controlled by suitably choosing the values of the Prandtl number Pr and local Eckert number E, local viscioelastic parameter k1 and local heat source/ sink parameter β.
10
Content available remote Time dependent MHD Couette flow due to ramped motion of one of the boundaries
Jha B. K., Jibril H. M.
International Journal of Applied Mechanics and Engineering
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2012
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Vol. 17, no. 2
383-399
EN
The effects of a transverse magnetic field on the Couette flow of an electrically conducting fluid between two infinite parallel plates have been discussed when one of the plates has been set into ramped motion. Under the assumption of a negligible induced magnetic field and applied magnetic field being fixed relative to the fluid or moving plate, the governing momentum equation has been solved exactly. The expressions for velocity field and skin-friction have been presented. The transient features of velocity and skin-friction have been discussed for different values of the Hartmann number. It is seen that the velocity field and skin-friction increases with an increase of the Hartman number when the magnetic field is fixed with respect to the moving plate while the result is just reverse when it is fixed with respect to the fluid.
11
Content available remote Effects of heat transfer on dusty gas flow past a semi-infinite vertical plate
Kulandaivel T.
International Journal of Applied Mechanics and Engineering
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2012
|
Vol. 17, no. 4
1339-1346
EN
Effects of heat transfer on dusty gas flow past a semi-infinite vertical plate with variable temperature is considered. The governing boundary layer equations for this problem are set up and non-dimensional governing equations are solved by an implicit finite difference scheme of Crank-Nicolson method, which is fast convergent and unconditionally stable. Gas velocity, dust particle velocity, temperature, skin-friction and Nusselt numbers are calculated numerically for various parameters and are shown graphically. It is observed that an increase in the mass concentration of dust causes a fall in the dusty gas velocity but an increase in the skin-friction.
12
Content available remote Analytical investigation of the hydromagnetic flow in a porous medium due to periodically heated oscillating plate
Sharma B. K., Sharma P. K., Chand T., Chaudhary R. C.
International Journal of Applied Mechanics and Engineering
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2012
|
Vol. 17, no. 4
1367-1375
EN
The Stokes second problem in the presence of a magnetic field in a porous medium is considered. The flow is due to an oscillating plate at the bottom of the porous medium of finite thickness and fully saturated with the viscous incompressible liquid. The plate is kept at oscillating temperature and a transverse uniform magnetic field is applied normal to the plate. It is assumed that the flow in the porous medium is governed by the Brinkman equations. The flows at the interface (porous medium-clear fluid boundary) are matched by the conditions suggested by Ochao-Tapia and Whittaker. Approximate solutions for velocity, temperature field, skin-friction and rate of heat transfer are calculated and effects of various parameters upon them are examined
13
Content available remote MHD natural convection flow past an impulsively moving vertical plate with ramped wall temperature in the presence of thermal diffusion with heat absorption
Seth G. S., Ansari Md. S.
International Journal of Applied Mechanics and Engineering
|
2010
|
Vol. 15, no 1
199-215
EN
Hydromagnetic natural convection flow of a viscous incompressible electrically conducting and heat-absorbing fluid past an impulsively moving vertical plate with ramped wall temperature in a porous medium, in the presence of thermal diffusion, is studied. The exact solution of momentum and energy equations, under the Boussinesq approximation, is obtained in closed form by the Laplace transform technique. The expressions for the skin friction and Nusselt number are also derived. The variations in fluid velocity and temperature are shown graphically whereas numerical values of skin friction and the Nusselt number are presented in tabular form for various values of pertinent flow parameters. The natural convection flow near a ramped temperature plate is also compared with the flow near an isothermal plate.
14
Content available remote Hydromagnetic flow due to ramped motion of the boundary
Jha B. K., Jibril H. M.
International Journal of Applied Mechanics and Engineering
|
2010
|
Vol. 15, no 4
1101-1109
EN
The unsteady flow of a viscous, incompressible and electrically conducting fluid subject to a uniform transverse magnetic field near a horizontal plate having ramped motion is considered. A unified closed form analytical solutions have been obtained for the velocity field and the skin-friction corresponding to the cases of a magnetic field fixed relative to the fluid or the moving boundary. Under the assumption of a negligible induced magnetic field, the governing momentum equation has been solved exactly by using the Laplace-transform technique. The flow formation near ramped motion of the plate has also been compared with the flow formation near a plate having constant motion (impulsive motion). It is observed that velocity of the fluid in the case of ramped motion of the plate is always less than that of the flow induced by impulsive motion of the plate.
15
Content available remote Numerical study of non-Darcy forced convective heat transfer in a power law fluid over a stretching sheet
Prasad K. V., Datti P. S.
International Journal of Applied Mechanics and Engineering
|
2009
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Vol. 14, no 2
473-488
EN
An analysis has been carried out to study the non-Darcy flow behavior and heat transfer characteristics of a non-Newtonian power law fluid over a non-isothermal stretching sheet with variable thermal conductivity and internal heat generation/absorption. Thermal conductivity is assumed to vary as a linear function of temperature. The partial differential equations governing the flow and heat transfer are converted into ordinary differential equations by a similarity transformation. The presence of non-Darcy forced convection and power law index leads to coupling and non-linearity in the boundary value problem. Because of the coupling and non-linearity, the problem has been solved numerically by the Keller box method. The computed values of horizontal velocity and temperature, boundary layer thickness are shown graphically in tables and figures. Several reported works on the problem are obtained as limiting cases of the present study. The results of the study have implications in extrusion processes and in other applications with porous media.
16
Content available remote Transient unsteady natural convection MHD flow past a semi-infinite verticaI plate with constant heat flux
Palani G., Ganesan P.
International Journal of Applied Mechanics and Engineering
|
2007
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Vol. 12, no 1
125-134
EN
A numerical analysis is performed to study the MHD flow of an electrically conducting, incompressible, viscous fluid past a semi-infinite vertical plate with constant heat flux, subjected to a transversely applied magnetic field. The heat due to viscous dissipation and the induced magnetic field are assumed to be negligible. The dimensionless goveming equations are unsteady, two-dimensional, coupled, and non-linear. A most accurate, unconditionally stable and fast converging implicit finite difference scheme is used to solve the non-dimensional goveming equations. Velocity and temperature of the flow have been presented graphically for various parameters. The local and average skin friction and Nusselt number are also presented graphically.
17
Content available remote Boundary layer MHD flow of a viscoelastic fluid over a porous quadratic stretching sheet
Khan S. K.
International Journal of Applied Mechanics and Engineering
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2005
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Vol. 10, no 2
267-279
EN
A mathematical analysis on the boundary layer MHD flow of a viscoelastic fluid over a porous stretching sheet has been presented in this paper. A typical choice of quadratic stretching of the boundary, which generates a quadratic part in velocity parallel to the boundary sheet and a linear mass flux part in the velocity normal to the stretching sheet, has been assumed. Streamline patterns and skin friction coefficients are discussed for various values of nondimensional physical parameters. The result of the analysis reveals that the combined effect of the non-dimensional viscoelastic parameter and Hartmann number is to increase significantly the values of skin friction coefficient, whereas, the combined effect of the nondimensional constant mass flux parameter and modified linear mass flux parameter is to reduce largely the values of skin friction coefficient. For positive values of the linear mass flux parameter the stream functions attain a positive slope away from the origin while they attain a negative slope everywhere for zero value. The limiting cases of our results yield the results of Andersson (1992) and Kumaran and Ramanaiah (1996).
18
Content available remote Unsteady free convection flow of a dusty gas past a semi-infinite inclined plate with constant heat flux
Ganesan P., Palani G.
International Journal of Applied Mechanics and Engineering
|
2004
|
Vol. 9, no 3
483-492
EN
A numerical solution for the flow of fluid with dusty particles past a semi-infinite inclined plate with a constant heat flux is obtained by an implicit finite difference method, which is unconditionally stable. Gas-velocity, dust-velocity, temperature, skin friction and Nusselt number are shown graphically. It is observed that the velocity of the dusty-gas decreases with decreasing the inclination angle 'phi' to the horizontal. An increase in the mass concentration of dust also causes a fall in the gas-velocity.
19
Content available remote Viscoelastic boundary layer MHD flow through a porous medium over a porous quadratic stretching sheet
Kumar Khan S., Sanjayanand E.
Archives of Mechanics
|
2004
|
Vol. 56, nr 3
191-204
EN
Boundary layer MHD flow of a viscoelastic fluid in a porous medium over a porous stretching sheet has been presented in this article. A typical choice of quadratic stretching of the boundary, having a quadratic part in velocity parallel to the boundary sheet and a linear mass flux in the velocity normal to the stretching sheet, constitutes the boundary conditions of the problem. The effect of various values of nondimensional physical parameters on streamline patterns and skin friction coefficient are discussed. Some of the important findings of the article are: (a) the flow is enhanced by the positive values of linear mass flux parameter and suppressed by the negative values of linear mass flux parameter; (b) the effect of permeability parameter is not significant when linear mass flux parameter takes zero or negative values; (c) the combined effect of reduction of the values of permeability parameter, Hartmann number and linear mass flux parameter is expected to reduce largely the values of skin friction coefficient.
20
Content available remote Transient free convection flow of dissipative fluid past an infinite vertical porous plate
Soundalgekar V. M., Uplekar A. G., Jaiswal B. S.
Archives of Mechanics
|
2004
|
Vol. 56, nr 1
7-17
EN
A finite-difference analysis of transient free convection flow of a dissipative fluid past an infinite vertical porous plate is presented here. Velocity, temperature, skin-friction and Nusselt number are shown graphically and the effects of different parameters on the flow field are discussed.
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