Mekonnen S. Ayano^1,*, Thokozani N. Khumalo¹, Stephen T. Sikwila², Stanford Shateyi³

Frontiers in Heat and Mass Transfer, Vol.22, No.4, pp. 1153-1169, 2024, DOI:10.32604/fhmt.2024.048474 - 30 August 2024

Abstract The present paper examines the temperature-dependent viscosity and thermal conductivity of a micropolar silver ()−Magnesium oxide () hybrid nanofluid made of silver and magnesium oxide over a rotating vertical cone, with the influence of transverse magnetic field and thermal radiation. The physical flow problem has been modeled with coupled partial differential equations. We apply similarity transformations to the non-dimensionalized equations, and the resulting nonlinear differential equations are solved using overlapping grid multidomain spectral quasilinearization method. The flow behavior for the fluid is scrutinized under the impact of diverse physical constraints, which are illustrated graphically. The More >

Kai Long¹, Ayesha Saeed¹, Jinhua Zhang², Yara Diaeldin¹, Feiyu Lu¹, Tao Tao³, Yuhua Li^1,*, Pengwen Sun⁴, Jinshun Yan⁵

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.1, pp. 43-67, 2024, DOI:10.32604/cmes.2023.031538 - 30 December 2023

Abstract This paper offers an extensive overview of the utilization of sequential approximate optimization approaches in the context of numerically simulated large-scale continuum structures. These structures, commonly encountered in engineering applications, often involve complex objective and constraint functions that cannot be readily expressed as explicit functions of the design variables. As a result, sequential approximation techniques have emerged as the preferred strategy for addressing a wide array of topology optimization challenges. Over the past several decades, topology optimization methods have been advanced remarkably and successfully applied to solve engineering problems incorporating diverse physical backgrounds. In comparison… More >

Yuming He^1,*, Jie Chen¹, Yubo Jiao¹, Wei Wang¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.26, No.2, pp. 1-1, 2023, DOI:10.32604/icces.2023.09061

Abstract In present study, a fast simulation algorithm based on linearization is used to simulate the flow parameters of the natural gas pipeline under transient operating conditions, analyze the impact of natural gas components on the transient operation, and conduct the tracking calculation of natural gas components [1- 3]. Under the condition that the simulation calculation accuracy is not affected, the first-order Taylor linearization expansion method is used to linearize the transient simulation model of natural gas pipeline, while the second-order implicit difference dispersion method is used to obtain the linearized discrete equations without initial value… More >

Salah-ud-din Khokhar^1,2,*, QinKe Peng¹, Muhammad Yasir Noor³

CMC-Computers, Materials & Continua, Vol.75, No.2, pp. 2413-2427, 2023, DOI:10.32604/cmc.2023.036148 - 31 March 2023

Abstract For fuzzy systems to be implemented effectively, the fuzzy membership function (MF) is essential. A fuzzy system (FS) that implements precise input and output MFs is presented to enhance the performance and accuracy of single-input single-output (SISO) FSs and introduce the most applicable input and output MFs protocol to linearize the fuzzy system’s output. Utilizing a variety of non-linear techniques, a SISO FS is simulated. The results of FS experiments conducted in comparable conditions are then compared. The simulated results and the results of the experimental setup agree fairly well. The findings of the suggested More >

Aamir Shahzad^1,*, Shadi Munshi², Sufyan Azam², Muhammad Nasir Khan³

CMC-Computers, Materials & Continua, Vol.73, No.2, pp. 2897-2911, 2022, DOI:10.32604/cmc.2022.028441 - 16 June 2022

Abstract The main objective of this research is to design a state-feedback controller for the rotary inverted pendulum module utilizing the linear quadratic regulator (LQR) technique. The controller maintains the pendulum in the inverted (upright) position and is robust enough to reject external disturbance to maintain its stability. The research work involves three major contributions: mathematical modeling, simulation, and real-time implementation. To design a controller, mathematical modeling has been done by employing the Newton-Euler, Lagrange method. The resulting model was nonlinear so linearization was required, which has been done around a working point. For the estimation of the controller More >

Ali Raza^1,*, Emad E. Mahmoud², A. M. Al-Bugami², Dumitru Baleanu^3,4, Muhammad Rafiq⁵, Muhammad Mohsin⁶, Muneerah Al Nuwairan⁷

CMC-Computers, Materials & Continua, Vol.71, No.3, pp. 5293-5310, 2022, DOI:10.32604/cmc.2022.024535 - 14 January 2022

Abstract Pine wilt is a dramatic disease that kills infected trees within a few weeks to a few months. The cause is the pathogen Pinewood Nematode. Most plant-parasitic nematodes are attached to plant roots, but pinewood nematodes are found in the tops of trees. Nematodes kill the tree by feeding the cells around the resin ducts. The modeling of a pine wilt disease is based on six compartments, including three for plants (susceptible trees, exposed trees, and infected trees) and the other for the beetles (susceptible beetles, exposed beetles, and infected beetles). The deterministic modeling, along More >

Stanford Shateyi^a,∗, Hillary Muzara^b

Frontiers in Heat and Mass Transfer, Vol.14, pp. 1-10, 2020, DOI:10.5098/hmt.14.18

Abstract A theoretical analysis has been carried out to investigate the influence of unsteadiness on the laminar two-phase magnetohydrodynamic nanofluid flow filled with porous medium under the combined effects of Brownian motion and thermophoresis. Thermal variable conductivity, thermal radiation and viscous dissipation effects are also considered in this numerical study. The highly nonlinear partial differential equations are transformed into a set of coupled nonlinear ordinary differential equations through suitable similarity transformations. The resultant ordinary differential equations are then numerically solved using the spectral quasilinearization method. The effects of the pertinent physical parameters over the fluid velocity, More >

N. Govindaraj, A. K. Singh, Pankaj Shukla

Frontiers in Heat and Mass Transfer, Vol.15, pp. 1-8, 2020, DOI:10.5098/hmt.15.20

Abstract A numerical study of fluid flow over stretching sheet with temperature dependent properties has been performed induced by mixed convection. The significant variation of the Prandtl number and viscosity in the temperature is observed [see table 1]. Viscosity and Prandtl number are vary in inverse of the linear function. The physical problem modeled in the mathematical equations in dimension form, which is converted to the non-dimensional equations by applying similarity transformations and suitable boundary conditions. The mathematical modelling problem is transformed PDE’s are numerically solved using Quasilinearization technique and FDM. The current numerical data has… More >

Qiping Chen^*, Haoyu Sun, Ning Wang, Zhi Niu, Rui Wan

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.3, pp. 513-524, 2020, DOI:10.32604/fdmp.2020.09375 - 25 May 2020

Abstract The possibility to enhance the stability and robustness of electrohydraulic brake (EHB) systems is considered a subject of great importance in the automotive field. In such a context, the present study focuses on an actuator with a four-way sliding valve and a hydraulic cylinder. A 4-order nonlinear mathematical model is introduced accordingly. Through the linearization of the feedback law of the high order EHB model, a sliding mode control method is proposed for the hydraulic pressure. The hydraulic pressure tracking controls are simulated and analyzed by MATLAB/Simulink soft considering separately different conditions, i.e., a sine More >

W. M. Abd-Elhameed^1,2,*, Y. H. Youssri²

CMES-Computer Modeling in Engineering & Sciences, Vol.121, No.3, pp. 1029-1049, 2019, DOI:10.32604/cmes.2019.08378

Abstract This paper is confined to analyzing and implementing new spectral solutions of the fractional Riccati differential equation based on the application of the spectral tau method. A new explicit formula for approximating the fractional derivatives of shifted Chebyshev polynomials of the second kind in terms of their original polynomials is established. This formula is expressed in terms of a certain terminating hypergeometric function of the type ₄F₃(1). This hypergeometric function is reduced in case of the integer case into a certain terminating hypergeometric function of the type ₃F₂(1) which can be summed with the aid of More >