Amir Pishkoo

Amir Pishkoo

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Research Focus & Metrics

Academic Career Length

15Years (2012-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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8 February 2021 in Fractal and Fractional
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APAmir Pishkoo
Amir Pishkoo
MDMaslina Darus
Maslina Darus
Navier–Stokes equations describe the laminar flow of incompressible fluids. In most cases, one prefers to solve either these equations numerically, or the physical conditions of solving the problem are considered more straightforward than the real situation. In this paper, the Navier–Stokes equations are solved analytically and numerically for specific physical conditions. Using Fα-calculus, the fractal form of Navier–Stokes equations, which describes the laminar flow of incompressible fluids, has been solved analytically for two groups of general solutions. In the analytical section, for just “the single-phase fluid” analytical answers are obtained in a two-dimensional situation. However, in the numerical part, we simulate two fluids’ flow (liquid–liquid) in a three-dimensional case through several fractal structures and the sides of several fractal structures. Static mixers can be used to mix two fluids. These static mixers can be fractal in shape. The Sierpinski triangle, the Sierpinski carpet, and the circular fractal pattern have the static mixer’s role in our simulations. We apply these structures just in zero, first and second iterations. Using the COMSOL software, these equations for “fractal mixing” were solved numerically. For this purpose, fractal structures act as a barrier, and one can handle different types of their corresponding simulations. In COMSOL software, after the execution, we verify the defining model. We may present speed, pressure, and concentration distributions before and after passing fluids through or out of the fractal structure. The parameter for analyzing the quality of fractal mixing is the Coefficient of Variation (CoV).

6 March 2019 in Fractal and Fractional
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FJFakhri Khajvand Jafari
Fakhri Khajvand Jafari
MAMohammad Sadegh Asgari
Mohammad Sadegh Asgari
APAmir Pishkoo
Amir Pishkoo
The major problem in the process of mixing fluids (for instance liquid-liquid mixers) is turbulence, which is the outcome of the function of the equipment (engine). Fractal mixing is an alternative method that has symmetry and is predictable. Therefore, fractal structures and fractal reactors find importance. Using F α -fractal calculus, in this paper, we derive exact F α -differential forms of an ideal gas. Depending on the dimensionality of space, we should first obtain the integral staircase function and mass function of our geometry. When gases expand inside the fractal structure because of changes from the i + 1 iteration to the i iteration, in fact, we are faced with fluid mixing inside our fractal structure, which can be described by physical quantities P, V, and T. Finally, for the ideal gas equation, we calculate volume expansivity and isothermal compressibility.

31 October 2022 in European Journal of Pure and Applied Mathematics
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MNMahlagha Noshad
Mahlagha Noshad
APAmir Pishkoo
Amir Pishkoo
MDMaslina Darus
Maslina Darus
In this work, we numerically solve ordinary and conformable fractional differential equations using Easy Java Simulations software. Their solutions, including homogeneous and non-homogeneous parts, are compared in various time intervals. Using software’s visualization andsimulation features, we may better examine, compare, and evaluate solutions of analytical and numerical fractional differential equations. A kind of oscillatory behavior is seen in long enough times. In simulation of diffusion and sub-diffusion processes, two intriguing events have been observed.

16 February 2012 in Journal of Inequalities and Applications
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APAmir Pishkoo
Amir Pishkoo
MDMaslina Darus
Maslina Darus
In this article, the univalent Meijer's G-functions are classified into three types. Certain integral, differential or differintegral transformations preserving the univalence of the Meijer's G-functions, have been discussed. This classification and transformations are based on Kiryakova's studies in representing the generalized hypergeometric functions as fractional differintegral operators of three basic elementary functions. In fact, these transformations are the Erdélyi-Kober operators (m = 1) or their two-tuple compositions (for m = 2) known also as hypergeometric fractional differintegrals. A number of new univalent Meijer's G-functions can be obtained by successive applications of such transformations, being operators of the generalized fractional calculus (GFC). Some new relations are then interpreted for the starlike, convex, and positive real part functions in terms of Meijer's G-functions. Mathematics Subject Classification (2000): 30C45; 33C60; 33E20.

1 July 2016 in Journal of Computational and Theoretical Nanoscience
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APAmir Pishkoo
Amir Pishkoo
MDMaslina Darus
Maslina Darus
RPRonak Pashei
Ronak Pashei
MAMohammad Sadegh Asgari
Mohammad Sadegh Asgari

6 November 2019 in International Annals of Science
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RPRonak Pashaei
Ronak Pashaei
MAMohammad Sadegh Asgari
Mohammad Sadegh Asgari
APAmir Pishkoo
Amir Pishkoo
In this paper the solution of conformable Laplace equation, \frac{\partial^{\alpha}u(x,y)}{\partial x^{\alpha}}+ \frac{\partial^{\alpha}u(x,y)}{\partial y^{\alpha}}=0, where 1 < α ≤ 2 has been deduced by using fractional fourier series and separation of variables method. For special cases α =2 (Laplace's equation), α=1.9, and α=1.8 conformable fractional fourier coefficients have been calculated. To calculate coefficients, integrals are of type "conformable fractional integral".