Abstract
Flow and heat distribution over a convergent or divergent channel plays a major role in aeronautical, pharmaceutical, dynamic, civil, climatic, and biomechanical engineering, as well as heat transfer through a porous medium, has piqued the interest of researchers due to its numerous aerospace and automotive manufacturing, including waste disposal, raw petroleum products, grain collection, porous coating, petroleum lagoons, groundwater pollution, packed-bed power plants etc. Further, addition of nanoparticles to base liquid will improve the thermal distribution. Based on the above affordable application the present study will focus on heat transfer enhancement in ternary nanofluids flows induced by stretched convergent or divergent channels. The mobility of ternary nanoparticles occurs in the porous zone. The uniform energy absorption and generation influence is included in the energy expression. Through the use of comparable variables, the flow expressions are transformed into a system of non-linear ODEs (ordinary differential equations). To tackle the problem, the Runge-Kutta-Fehlberg fourth and fifth order (RKF-45) scheme with shooting procedure is adopted. The nature of imposing limitations on physically significant quantities is explored and carried out. The augmentation in solid volume-fraction of both stretched/shrinked channels resulted a reduction in temperature. Furthermore, it is found that the increasing heat sink or source factor and Eckert number augmented the rate of energy transport in the diverging channel, but reverse nature is found in the converging channel. It is also noticed that the ternary nanofluid has a greater impact than the hybrid and mano-nanofluid.
Keywords
Introduction
In recent days, the thermal transportation of nanofluids and nanomaterials play a critical role in the development of modern products. Oils, ethyl glycol, and water are poor heat transfer liquids; however, by dipping these liquids into nano-sized materials, the thermal conductivity of these liquids can be improved significantly. Choi and Eastman 1 experimented the idea of nano liquid for the first time in 1995. They found that the thermal efficiency is enhanced significantly when compared to the base liquid. Later, Kang et al. 2 experimentally checked these results. Khanafer et al. 3 had examined the thermal distribution concert inside the closed cage containing nano liquid immersed in solid particles. Nanofluids have emerged as one of the significant pillar in the industrial revolution. Nanoliquids have wide range of applications in the field of physical sciences, biological sciences, electronics, transportation, nuclear controlling, environment as well as the security of the nation. Recently, Madhukesh et al. 4 investigated the Bio-Marangoni convection flow of Casson nano liquid via a porous media with chemically reactive activation energy. Abbasi et al. 5 deliberated the effectiveness of various temperature dependent nanoparticles along with Joule heating and mixed convection. Upreti et al. 6 made a numerical investigation on flow of Sisko nanoliquid over a stretched surface in Darcy-Forchheimer porous medium with heat radiation. Wakif et al. 7 conducted a meta-analysis on the thermal-migration of nano/tiny-sized particles in the movement of various fluids. As the industries demand more thermal distribution, existing nanoliquids are mixed with another diverse type of particles, which resulted new type of nanofluid called as hybrid nano liquid. These types of fluids exhibit more thermal conductivity when compared to normal nanoliquids. These fluids were later on replaced by nano liquid in large-scale industries. Ramesh 8 reported the shape factor influences on hybrid nanofluid through viscous heating. Madhukesh et al. 9 addressed the thermophoresis and convective heating condition influences on the hybrid nanomaterials flows induced by the movement of thin needle. Akbar et al. 10 executed the ion-slip and Hall current aspects in hydromagnetized biologically inspired hybrid nanomaterial flows. Joshi et al. 11 explored into the heat and mass distribution investigation of magneto hybrid nanofluid motion with volumetric thermal production. In the 21st century, some researchers shown interest in enhancing the thermal distribution, for this another nanoparticle is being added to the hybrid type nanofluid called as modified nanofluid. Basically, it is a mixture of three distinct nanoparticles in the base liquid. Nadeem and Abbas 12 studied the modified nanofluid flow over a stretching sheet in the presence of porous medium. Abbas et al. 13 investigated the modified nanofluid under time-dependent viscosity induced by the Riga plate.
Many researchers paid attention to address the heat source or sink effect because it maintained the thermal distribution of the system. Thermal performance of the liquids is controlled with the help of heat source or sink during the liquid motion. This physical effect is widely used in the manufacturing of plastic as well as rubber sheets, removal of waste material contains radioactive nature. Recently, the evaluation of heat sink and source influences on versatile fluid flow problems is executed by distinct investigators. The nanofluid flow and thermal distribution in converging and diverging walls under energy source or sink effects is addressed by Dogonchi and Ganji. 14 Pandey and Kumar 15 examined the MHD flow over stretched and shrinked channels under heat source-sink by using cu-water nanoliquid. Ramesh et al. 16 deliberated the heat transmission analysis of aluminum alloys and magnetic graphene oxide nanoparticles. Ramesh and Madhukesh 17 analyzed the activation energy mechanism in hybrid carbon nanotubes with heat source/sink. Upreti et al. 18 investigated the Ohmic heating and non-uniform heat sink/source roles on 3D Darcy-Forchheimer CNTs nanofluids flows. Singh et al. 19 examined the slip micropolar liquid flow through a permeable wedge.
Porous medium plays one of the major roles in the branches of medical and industrial sciences. In biological area, transportation process in the human kidneys and lungs, stone present in the glad bladder, arteries clogging and even in the blood vessels. We can also observe porous medium naturally in our nature for example wood, limestone, leakage of water in the river buds. From the above point of view, enormous application in the scientific, metallurgy and earth science researchers studied the porous medium. Kumar et al. 20 studied the oscillatory hydromagnetic convected energy transfer in converging/diverging channel immersed in porous medium. Akinshilo 21 studied the nanofluid porous medium in converging/diverging channel using Akbari Ganji method. Ahmad et al. 22 deliberated the time-dependent Walter-B nanoliquid flow in the presence of porous space and heat generation. Pandey and Kumar 23 investigated the effects of natural convection and heat radiation on nano liquid mobility in a porous media with viscous dissipation over stretching cylinder. Singh et al. 24 used the Keller-Box approach to study the micropolar fluid flow with melting heat transportation and chemical reaction.
Nowadays, growing technologies and industries require devices contain long life duration, better functioning and exact performance. The study over a converging and diverging wall has wide range of application due to its industrial, biological and physical implications. The converging-diverging channel has been widely used in flows over river, cannel, and streams. One of the amazing ways in the human body is the flow of blood through capillaries that are connected to arteries. Rashid et al. 25 studied the shape effect of nanoparticles over converging/ diverging channel. The Darcy-Forchheimer model of hybrid nanomaterial flow over stretched convergent-divergent channels is simulated by Ramesh et al.. 26 Saifi et al. 27 analysed the thermal distribution in converging-diverging channel through Adomian decomposition scheme. Adnanet al. 28 examined the analytical and numerical calculation of thermal radiation effects over a stretchable converging-diverging channel. Dogonchi and Ganji 29 deliberated the MHD nanofluids flows over stretchable/shrinkable thermally radiated convergent-divergent channel. Mishra et al. 30 studied the nanoparticle role and energy generation/absorption on stretching shrinking nanofluid in the presence of nanoliquid.
The present work status is compared with the previously conducted works and it is shown in the above table. Based on the above-served literature, even though many researchers conducted work on convergent divergent channels in the presence of mano and hybrid nanofluids but no one studied the influence of modified nanofluid in the presence of the porous medium, heat source, or sink and stretching/shrinking effect. This is the first work conducted on modified nanofluid.
Mathematical modeling of the problem
Consider a steady, incompressible, two-dimensional flow of a modified nanofluid containing copper

Geometry of the mathematical model.
Conservation of mass equation
The following similarity variables are introduced:
The effective thermophysical properties of modified nanofluid are given by (see Usman et al..33)
The following equations are obtained when substituting similarity variables (6) into (1) to (5) and by the elimination of pressure term,
In this paper we studied four cases, namely
The important engineering coefficients are given by
Numerical procedure with code validation
The reduced ODEs (8) and (9) with conditions (10)arenumerically solved with the help of well-known mathematical computing software Maple. RKF45method via shooting process is implemented.Since, the derived problem is two-point boundary value and higher order. The problem is firstly reframed into and initial value and first order problem.
The above initial value problem is numerically simplified by guessing the missing value by implementing shooting technique by assigning parameters value. The error tolerance is taken as
The algorithm for RKF-45 order is given as (see35–37)
Runge -Kutta technique 4th order
For numerical computations, the flow parameter values are constrained, such as
Results and discussion
The graphical results of the physical parameters on velocity and temperature fields are elaborated in this section. Figure 2 established the comparison between nanofluid, hybrid nanofluid and ternary nanofluid for the velocity field and temperature field. The velocity curve for the nanofluid is slightly higher than the velocity curve of hybrid and ternary nanofluids. Because of the presence of nanoparticles, the thickness of the boundary layer will be increased. The accumulation of several nanoparticles gradually reduces the velocity profile but thermal distribution increases. Moreover, hybrid nanofluid and ternary nanofluid have similar influence on velocity. A significant rise in temperature for nanofluid is observed against the temperature curves of hybrid and ternary nanofluids. Furthermore, the temperature curve of hybrid nanofluid is higher than the ternary nanofluid temperature curve. Figure 3 illustrated the importance of

Comparison between nanofluid, hybrid nanofluid and ternary nanofluid on (a) velocity (b) temperature.

Velocity curve for various

Temperature curve for various

Velocity curve for various S in divergent and convergent channel cases.
Validation of the present numerical method with the published method when
Figure 6 is reported to discuss the shrinking parameter influence onto temperature field against two different scenarios of convergent and divergent channel. Due to increase in the wall shrinking rate, the temperature field is reduced for both cases of convergent channel

Temperature curve for various S in divergent and convergent channel cases.

(a) velocity (b) temperature curves for various
Supplementary Fig. 8 represents the effect of Reynolds number on velocity and temperature fields for shrinking convergent and divergent channel scenarios. Similar kind of behavior of Reynolds number on velocity and temperature curves is observed for Supplementary Fig. 8 as in case of Figure 7. The significance of porous medium is characterized in supplementary Fig. 9 for divergent and convergent stretching channel. The porous medium offers larger resistance to the fluid movement. As a result, the velocity and temperature fields are enhanced when stretchable channel walls approaching and diverging from each other. However, the velocity and temperature curves for convergent channel case are larger as compared with the divergent channel. Supplementary Fig. 10 explains the porosity parameter influence on f and g for convergent and divergent channel with shrinking walls. Similar kind of observations for the curves (f and g) against
Supplementary Fig. 11 portrays the importance of
Supplementary Fig. 13 is elaborated the implementation of Eckert number on temperature field for convergent and divergent channel. In supplementary Fig. 13(a), the temperature field for stretchable channel (convergent and divergent) case is modified against the Eckert number. For converging channel walls, the temperature curves are higher than those obtained for the divergent channel. In supplementary Fig. 13(b), same behavior in temperature profiles is noticed for convergent and divergent channel with shrinking wall case. However, the temperature curves attained against shrinking walls are larger form the temperature curves obtained for the stretchable channel. The Eckert number is used to describe the influence of self-heating in a fluid as a result of dissipation effects. At high flow velocities, the temperature profile in a fluidic system is dominated not only by the temperature gradients existing in the system, but also by the effects of dissipation owing to fluid internal friction. This will cause self-heating and, as a result, a shift in the temperature profile.
The heat source/sink parameter influence onto the temperature field in convergent and divergent channel is illustrated through supplementary Fig. 14. In supplementary Fig. 14(a), the channel walls are stretchable while in supplementary Fig. 14(b), the walls of the channel are shrinkable. Here,
Supplementary Fig. 15 is plotted in order to estimate the skin-friction co-efficient and local Nusselt number against mano nanofluid, hybrid nanofluid and ternary nanofluid for different values of
Table 1 presents the validation of numerical technique under limiting case with.
27
Shear stresses are calculated for stretching and shrinking channel with the channel walls approaching and moving away from each other. Excellent agreement of the values
Table 2 presents the computational values of skin-friction co-efficient
Numerical computational values of
Conclusions
The distribution of flow and heat through a convergent or divergent channel is important in aeronautical, pharmaceutical, dynamic, civil, climatic, and biomechanical engineering. The thermal phenomena of ternary nanomaterials in stretchable/shrinkable convergent and divergent channels was included in the current work. The movement of the ternary nanofluids is characterized by the porous zone. The impact of the energy source/sink was involved in the energy equation. RKF-45 provides a numerical solution to the flow issue as well as a shooting process. The primary consequences are as follows:
The temperature field is lowered in the case of a stretchy convergent channel, but the reverse behavior is observed in the case of a stretchable divergent channel. The thermal phenomenon is declined for both cases of shrinkable convergent and divergent channel. For the stretching/shrinking convergent and divergent channels, the temperature curves are changed against the porosity parameter and lowered through the Reynolds number. The Eckert number increases the thermal field for convergent/divergent stretching and shrinking channels. For the stretching/shrinking channel, the porosity parameter reduces skin friction Local Nusselt number is increased in the case of a divergent channel and decreased in the case of a convergent channel against the heat source/sink parameter. Ternary nanofluid shows significant impact than hybrid and mano fluids in surface drag force and rate of heat transfer phenomenon.
Supplemental Material
sj-docx-1-pie-10.1177_09544089221081344 - Supplemental material for Ternary nanofluid with heat source/sink and porous medium effects in stretchable convergent/divergent channel
Supplemental material, sj-docx-1-pie-10.1177_09544089221081344 for Ternary nanofluid with heat source/sink and porous medium effects in stretchable convergent/divergent channel by G.K. Ramesh, J.K. Madhukesh, S.A. Shehzad and A. Rauf in Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering
Footnotes
Declaration of conflicting interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The author(s) received no financial support for the research, authorship and/or publication of this article.
Supplemental material
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References
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