1. Introduction
The Eyring-Powell fluid model is a significant non-Newtonian fluid model developed to address the limitations of classical Newtonian and non-Newtonian models in representing real fluid behavior. Based on statistical mechanics and inspired by the Eyring theory of reaction rates, it provides a more accurate description of viscosity variations with shear rate changes. This model is particularly useful in applications involving shear-thinning behavior without the singularity issues of power-law fluids. Unlike the Casson model, the Eyring-Powell model does not require a yield stress to initiate flow. This model is used widely in industries that involve lubricants, polymer processing, and biological fluids, including blood flow in larger arteries. The effects of DuFour and Soret on boundary layer flow of Eyring-Powell nanofluid over a cylinder with viscous dissipation effects were analyzed [
1]. They used non-similarity solution with bvp4c MATLAB R2017b built in function to evaluate numerically solution of the considered problem. The effects of thermal radiation and thermal conductivity variation on chemically reactive, free convective Powell-Eyring nanofluid flow around a cylinder were analyzed theoretically [
2]. Furthermore, heat transfer in Eyring-Powell fluids has been explored in different settings, including MHD systems with viscous dissipation [
3], fluid flow inside a pipe [
4], oscillatory flow in a porous channel with energy-dependent viscosity [
5], and radiative and chemically reactive flows incorporating non-Fourier heat flux and non-Fick mass flux theories [
6].
Gaffar et. al. [
7] investigated numerical solution of MHD boundary layer flow of tangent hyperbolic fluid over a cylinder using implicit finite difference scheme known as Keller Box method. The effects of ternary nanoparticles i.e., titanium oxide, silicon oxide and aluminum oxide (
TiO2–SiO
2–
Al2O3) on boundary layer flow of non-Newtonian model was examined by Turabi et al. [
8]. They investigated that the increasing nature of viscous dissipation effects results in the improvement of thermal boundary layer. According to their investigation, thermal boundary layer improves as viscous dissipation effects upsurge. Convective heat transport analysis of non-Newtonian nanofluid with two-layer viscous dissipative effects in a channel was studied by Amin et al. [
9]. Das et al. [
10] investigated dynamical behavior of MHD boundary layer flow of hybrid nanofluid in a gyrating channel. The hydrodynamic nature of MHD gyrating stream of hybrid nanofluid flow of non-Newtonian model were addressed in a vertical plate [
11]. They concluded that presence of Coriolis and Lorentz forces with Hall currents significantly alters the fluid motion. Das et al. [
12] scrutinized hydro-thermal dynamics of magnetized rotational non-Newtonian hybrid nanofluid. There is a lot of literature is available to explore the fascinating phenomena of hybrid nanoparticles and non-Newtonian fluid [
13,
14,
15,
16,
17]. Saeed et al. [
18] explored the effects of hybrid nanoparticles on MHD boundary layer flow with couple stress. Shoaib and Javed [
19] examined sensitivity of convective boundary layer flow nanofluid with non-isothermal condition. Amin et al. [
20] inspected MHD impact on boundary layer flow of nanofluid in a two-layer vertical channel and they concluded that momentum and thermal boundary layer increases against the raising value of magnetic field. The consequences of non-linear thermal radiation (
) and chemical reaction (
) on unsteady boundary layer flow of hybrid nanofluid was addressed by Qayyum et al. [
21]. Amin et al. [
22] addressed a comparative analysis of MHD boundary layer flow of hybrid nanofluid. The study of Peristaltic transportation of blood flow through a ciliated micro-vessel wall was addressed [
23]. Khan et al. [
24] examined flow stability of non-Newtonian fluid over a wedge flow and they computed eigenvalues with perturbation scheme. Prasad et al. [
25] explored numerical investigation of non-Newtonian Jeffery nanofluid within flow of horizontal cylinder in a non-Darcy porous media. The importance of non-similar boundary layer flow is elaborated and addressed by many scholars due to their wide range of applications [
26,
27,
28,
29,
30]. Chu et al. [
31] examined radiative thermal analysis of hybrid nanoparticles with Keller-box approach an implicit finite-difference scheme numerically. There is a wide range of literature is available [
32,
33,
34,
35].
Cylinder is a critical topic in the study of boundary layer flows, especially in fluid dynamics and aerodynamics. To comprehend drag, heat transmission and separation phenomena in boundary layer flows, one must examine the fluid’s behavior close to a surface. The properties of the boundary layer may be drastically altered by cylinder. Aerodynamic surfaces, such as wings and turbine blades, may benefit from cylinder in boundary layer flows to improve efficiency and performance via management of the boundary layer. Cylindrical surfaces are also used to speed up the movement of heat in heat exchanges and cooling systems. Therefore, author apply the supervised machine learning technique based on artificial neural network simulation to examine the heat transfer phenomena through a circular cylinder.
2. Mathematical Formulation
Considered 2-D, incompressible, and steady MHD boundary layer flow of non-Newtonian hybrid nanofluid over a horizontal, permeable circular cylinder that is embedded in a porous medium with heat source/sink and viscous dissipation A non-Newtonian Eyring-Powell hybrid nanofluid is considered in this investigation. The well-known Tiwari-Das model [
32] is incorporated in this study to examine the effects of hybrid nanoparticles i.e., titanium oxide and Copper oxide (
,
) on momentum and thermal boundary layer. The
-axis is used for horizontal cylinder’s circumference, while
-axis is used for normal to surface. Here, ‘
’ stands for horizontal cylinder’s radius.
, is a y-axis angle as
. Additionally, cylinder’s radial direction receives application of uniform magnetic field’s intensity
. Gravity is represented as “
”. The boussineq approximations are assumed to be valid. Let the hybrid nano fluid’s constant temperature ‘
’ and its ambient temperature ‘
’. The governing equations for momentum and thermal boundary layer are defined as follows [
36]:
where
Figure 1 is the physical representation for investigated model,
Table 1 and
Table 2 displays thermophysical properties of the base fluid and hybrid nanoparticles. To solve the flow problem, following boundary conditions are incorporated as;
Defined stream function is
. Since continuity equation is satisfied,
is specified by
and
. We now express dimensionless quantities as follows:
We substitute Equation (7) into Equations (2) and (3). Then following dimensionless PDEs are obtained:
The dimensionless boundary conditions are transformed:
The parameters which appear in Equations (8) and (9) are magnetic parameter is define as
,
shows Prandl number (
), Darcy parameter is presented as
, where
[
36], thermal radiation parameter
, Ecart number
, Richardson number
,
is a heat source sink, Reynold number
, Eyring-powell fluid parameter
, and concentration grashof number
. The coefficient of skin friction and Nusselt number are defined as follow;
where
and
are given as
After applying a non-similar transformation Equation (11) become
where
and
.
5. Results and Discussion
The main goal of this study is to investigate the flow of a non-Newtonian Eyring-Powell Hybrid Nanofluid (EPHNF) model past a horizontal cylinder immersed in a porous medium with viscous dissipation and heat source sink effects. The Tiwari-Das model is used to develop flow problem for hybrid nanoparticles over a horizontal cylinder [
35]. The Local Non-Similarity solution technique is used to numerically solve boundary layer flow of a Eyring-Powell Hybrid Nanofluid (EPHNF) across a cylinder up to a third level of truncation Equations (21)–(27). In local non-Similarity solution technique, all values on the right side of the equation that take the form of
will be eliminated at first level of truncation. In second truncation level, we define a new function
and replace the old function in the form of
by these new functions. Similarly, for third level of truncation, a new function was defined and the equation was solved.
The pertinent parameters (i.e.,
,
,
,
, and
) of interest are shown in
Table 3.
Table 4 displays the gradient, Mu, and MSE tabulated values for boundary layer flow of non-Newtonian hybrid nanofluid for scenario 1 of cases 1 to 3. In
Table 4, performance is [
and
] is attain against iterations [517, 68, and 37], however
is noted to be
and 1.00
. ANN defines an error or cost function that quantifies the difference between actual and predicted results with MLP-ANN. One simple method for measuring error is to use Mean Squared Error (MSE). The training outcomes of the suggested ANN techniques are displayed in
Figure 4a for scenario 1 of cases 1–3. It is clear that MSE valuations, which were high in the early training parts, decline as the number of epochs diminishes. MSE values are decreased at each epoch in accordance with the function of MLP model, and ANN schemes’ training session concludes when the smallest MSE values are acquired since maximum accuracy has been attained. These low MSE values show that the developed ANN algorithms’ training phase effectively employed very minimal error levels.
Figure 4b displays the training setting for ANN methods. Network parameter optimization is made possible via gradient descent, which moves in the opposite direction of the gradient of the loss function. As epoch values fall, the gradient increases, as shown in
Figure 4b. Consequently, the verification tests have no value. Error histogram displays the error between actual and predicted values during ANN training. These error show how the actual and predicted outcomes differ.
Figure 4c displays the error histogram between estimated and actual values of numerical data of the proposed non-Newtonian Eyring-Powell hybrid nanofluid past a horizontal cylinder. It is detected that the error plots reveal that error rates attained for each data point close to zero error-line. The current state of the data used for testing, training, and validating ANN schemes is shown in
Figure 4d. Function curve is plotted in
Figure 4d to show that the output
satisfy the boundary condition. The plots show the target data on
-axis and outputs of ANN schemes on
-axis. The proximity of the data points to the zero-error line indicates that error between target data and ANN’s predicted value is low, while the fitted line is close to zero line, indicating that the average error is also significantly reduced.
values that are nearly equal to one are strongly associated with improving accuracy of ANN algorithm. Furthermore, it should be noted that each step’s calculated
values are nearly equal to 1.
Figure 4d makes it clear that ANN algorithm is developed in order to produce a predicted value. In ANN, a function fit plot is basically a visual representation of how the model’s outputs match actual outputs during the training or testing phase.
Figure 4e provides a visual evaluation of ANN model’s performance. The ANN model vanished at about
error-line, according to graphs, and expected and actual outputs of model roughly match.
Table 5 displays the gradient, Mu, and MSE tabulated values for scenarios 2 case 1–3. The numerical value of gradient as
Mu as
and MLP-ANN performance as
, and
against the epochs 10,11, and 10.
Figure 5a provides a visual representation of MSE for scenario 2.
Figure 5a demonstrated the convergence of the proposed MLP-ANN model, and it is shown that the accuracy was reached at
.
Figure 5b displayed the gradient’s graphical representation for scenario 2.
Figure 5b shows that the convergence rata is
while moving in opposite direction as the gradient of the loss function. The error histogram between predicted and actual values of the proposed fluid model beyond a horizontal cylinder is displayed in
Figure 5c. The linear regression and correlation index for scenario 2 are shown in
Figure 5d. When the correlation index value is close to 1, the best-fitting model is shown. According to
Figure 5d,
.
Figure 5e displays the ideal curve fitness function for scenario 2.
Table 6,
Table 7,
Table 8 and
Table 9 displays computed results for the gradient, Mu, and MSE for cases 1–3 of scenarios 3–6. The MLP-ANN most effective Gradient value for case 1 of scenario 3–6 is at [
],
], [
] and [
] against epoch [10, 10, 9], [48, 19, 15], [119, 217, 19], and [145, 146, 25] respectively. The calculated values of Mu and performance for case 1–3 of scenarios 3–6 are [
and
and
,
],
respectively. In
Figure 6a,
Figure 7a,
Figure 8a and
Figure 9a, MSE for scenarios 3–6 is displayed graphically. According to
Figure 6a,
Figure 7a,
Figure 8a and
Figure 9a, precision of proposed ANN model is
,
and
respectively. For scenarios 3–6,
Figure 6b,
Figure 7b,
Figure 8b and
Figure 9b displayed the gradient curve convergence of non-Newtonian hybrid nanofluid solution past a horizontal circular cylinder. The error histogram for situations 3–6 is displayed in
Figure 6c,
Figure 7c,
Figure 8c and
Figure 9c. The linear regression and correlation index for scenarios 3–6 are shown in
Figure 6d,
Figure 7d,
Figure 8d and
Figure 9d. For scenario 3–6 of
Figure 6e,
Figure 7e,
Figure 8e and
Figure 9e show the curve fitness function.
The matrices pertaining to values and patterns in the residual are displayed in
Table 10. For scenarios 1–6, these matrices have realistic characteristics that are similar to Sum of Square Error (SSE), R-square (
), Adj R-sq, and MSE. The following factors are observed when looking for matrices. The R-square and Adj R-sq values are close to one, as can be shown in
Table 10, suggesting a strong relationship between actual and expected values in scenarios. Furthermore, the model’s suitability is demonstrated by high numerical values of R-square and Adj R-square, which are close to zero. However, the model correctness is addressed via RMSE. The Root Means Squared Error (RMSE) number is low, as
Table 10 demonstrates. The fact that RMSE and SSE differ depending on the situation suggests that the model’s prediction might not be accurate for different data sets.
The residual graph can be used to assess how well a model matches the data. The residual should preferably be randomly distributed around zero to demonstrate that there isn’t a systematic error. For scenarios 1–6,
Figure 10a–e displays the residual analysis of MHD boundary layer flow of a non-Newtonian Eyring-Powell hybrid nanofluid across a horizontal porous cylinder.
Figure 11 illustrates how the radiation parameter
affects MHD boundary layer flow of a hybrid nanofluid past a horizontal porous cylinder. The
is crucial when examining fluid velocity and heat transfer in MHD boundary layer flow of non-Newtonian hybrid nanofluids. Fluid velocity increases as
values rise, as shown in
Figure 11.
Figure 12 shows the impact of
on boundary layer flow of hybrid nanofluid flows past a porous cylinder.
Figure 12 illustrates velocity will decrease when Eyring-Powell fluid parameter (
) increases.
Figure 13 Show the velocity of boundary layer flow of a hybrid nanofluid along a horizontal porous cylinder dramatically drops as δ increases. This property is particularly helpful in applications like electromagnetic flow control, where stabilizing fluid motion or reducing flow velocity are the main objectives.
It is noted that when there is MHD in flow, the Lorentz force increases which opposes the flow. This phenomenon is highlighted in
Figure 14 which shows when the value of
increases then velocity of fluid decline across a horizontal porous cylinder. It illustrates the graphical conclusion for velocity with the influence of magnetic parameter; the equation’s velocity decreases when
is increase.
Figure 15 show the influence of a parameter
on the flow of a boundary layer Eyring-Powell hybrid nanofluid across a horizontal porous cylinder. It illustrates the graphical conclusion for velocity with the influence of the heat source/sink, the equation’s velocity increases when
is increase.
In
Figure 16, using water as basis fluid, hybrid nanoparticles, such as
, and
, are present.
Figure 16 discusses the effects of Richardson’s number (
) on velocity. The velocity close to the surface decreases as effects of
increases.
Figure 17 demonstrates the impact of the radiation parameter (
) on hybrid nanofluids that are non-Newtonian. The relative significance of radiative heat transfer in relation to conductive heat transfer is indicated by the radiation parameter. It is essential in situations where thermal radiation cannot be disregarded and in high-temperature systems. The behavior of heat transfer systems under varied thermal and fluid flow conditions can be better understood and predicted by scientists and engineers through analysis. It has been noted that when Rd increases, the fluid’s temperature rises.
Figure 18 Show the impact of the Eyring-Powell parameter on fluid temperature. The molecular relaxation and flow resistance under stress are represented, respectively, by the Eyring-Powell parameters. Since these parameters provide details on the fluid’s non-Newtonian characteristics and stress tolerance, the model can be used to a wide range of scientific and technical problems. Viscosity dissipation is applied to an Eyring-powell fluid in the boundary layer outside of a horizontal cylinder.
Figure 18 shows that the temperature of the fluid increases as the value of ε increases.
Figure 19 Show the effect of the Concentration Grashof number
on fluid temperature. Concentration Grashof number accounts for the importance of buoyancy-induced flow due to concentration gradients. It finds important uses in the study of flows that are mostly caused by solute convection, specifically in the field of environmental processes and natural convection systems, as well as in certain industrial applications. As seen in
Figure 19, that the temperature of the fluid is overlapping when increases the value of
.
Figure 20 discussed the magnetic parameter
effect on the boundary layer flow of hybrid Nano fluid past a horizontal porous cylinder.
represents how strongly the magnetic field affects the fluid flow. The parameter value is large if magnetic forces dominate inertial forces. Calculating
has immense importance in designing and analyzing systems of conducting fluids under the influence of a magnetic field. As seen in
Figure 20, Temperature is increase when increase the value of
M.
Figure 21 discussed the heat source/sink (
) effect on the boundary layer flow of hybrid Nano fluid past a horizontal porous cylinder in a heat transfer problem, the heat source/sink term has a major impact on the flow behavior, energy balance, and temperature distribution. As seen in
Figure 21, Temperature increases when
increase.
Figure 22 discusses the impact of Richardson’s parameter (
) on boundary layer flow of hybrid Nano fluid past a horizontal porous cylinder temperature. Richardson’s parameter helps characterize the kind and behavior of convection within a system by indicating whether the flow is dominated by buoyancy forces (natural convection) or shear forces (forced convection).
.
As seen in
Figure 22, Additionally, it is noted that the temperature profile asymptotically meets the boundary requirement. The rate of temperature decreases when increases the value of
. Also, in
Table A1 Comparison of
for different values of Pr with previous works [
30,
31,
32,
33,
34,
35,
36,
37,
38,
39,
40,
41] and it is clear that, the present values are same obtained in [
41].