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Induction heating is widely used in industrial furnaces due to its rapid response and energy efficiency. Computer-aided modelling and simulation are necessary for the design and optimisation of these furnaces. This article focuses on modelling and simulating induction heating of a one-dimensional spatial partial differential model for a rectangular carbon steel billet. The simulation considered temperature dynamics, including the skin effect and heat loss via radiation. The partial differential model was converted into a state-space model for designing a full-state feedback Linear Quadratic Regulator (LQR) with integral action. This controller was effectively applied to regulate the billet’s core temperature from 1000 °C to 1200 °C, under different input, R and state, Q, weighing matrices for the LQR, as well as in the presence of disturbances.

• Free vibrations of an FGM anisogrid lattice hell perfectly filled with viscoelastic foams is investigated. • Modeling of the lattice part composed of spiral and hoop ribs is accomplished according to a global continuous standard based on orthotropic deep shells. • Kelvin–Voigt model is used to model the viscoelastic properties of the media. • Chebyshev collocation-based semi-numerical method is implemented to detect the system's frequencies and loss factors. Our aim with this paper is to model and investigate the vibration and damping of a new hybrid composite shell. The considered composite cylindrical shell includes an FGM anisogrid lattice shell perfectly filled with viscoelastic foams. The modeling of the lattice part composed of spiral and hoop ribs is accomplished according to a global continuous standard based on orthotropic deep shells. The distribution pattern of the metal and ceramic constituents along the lattice ribs is specified by a power law. The homogenizations between ceramic and metal phases within the ribs, as well as between the FGM lattice structure and foam, are governed by the rule of mixtures. Based on the transferred Kelvin–Voigt viscoelastic scheme, the dynamic moduli of the foam portion are acquired. Because viscoelastic foam is a soft material, the higher-order shear deformation shell theory is used to estimate the system's displacement components. After emanating the dynamic equations by Hamilton's principle, the Chebyshev collocation-based semi-numerical method is implemented to detect the system's frequencies and loss factors. The comprehensive results show the role of each composite characteristic in the vibration and damping behavior of the defined structure. [ABSTRACT FROM AUTHOR]

Development of a simple, easy and low-cost software for designing of waveguide-coupled single and cascaded microring resonator (MRRs) using semi-numerical calculation based on transfer matrix method (TMM), is presented in this paper. The software uses a device model which is embedded on the high index contrast (HIC) structure of silicon-on-insulator (SOI) with monomodal cavity for TE-mode polarizations, operating around 1550 nm optical wavelength. The main aim of the software is to estimate the microring resonator performance parameters, such as free spectral range (FSR) and quality factor (Qfactor). The software is very simple and easy to use. With a standard laptop computer, it only takes few seconds to obtain transmission response, FSR and Q-factor of single MRR for varied waveguides separation distance and ring radius. The results were then verified using simulation method based on finite integration technique using 3D electromagnetic simulator, which need a high memory and processor of computer and take days to execute the simulation. We found only small discrepancy, which in averages are about 4.25% and 10.80% for FSR and Q-factor, respectively. In general, the results obtained from this software are closer to 3D electromagnetic simulation results. [ABSTRACT FROM AUTHOR]

In this article, smart control and frequency characteristics of a graphene nanoplatelets composite (GPLRC) cylindrical shell surrounded by piezoelectric layers as sensor and actuator (PLSA) are presented. The current structure is under an external load. For the semi-numerical method, the strain-stress relations can be determined through the first-order shear deformable theory (FSDT). For access to various mass densities as well as the Poisson ratio, the rule of the mixture is applied, although the modified Halpin-Tsai theory for obtaining the module of elasticity. The external voltage is applied to the sensor layer, while a Proportional-Derivative (PD) controller has been utilized for controlling the output of the sensor. The boundary conditions are derived through governing equations of the GPLRC cylindrical shell surrounded by PLSA using an energy method known as Hamilton's principle and finally are solved using a generalized differential quadrature method (GDQM). Apart from a semi-numerical solution, a finite element model was presented using the finite element package to simulate the response of the smart GPLRC cylindrical shell. The results created from a finite element simulation illustrates a close agreement with the semi-numerical method results. The outcomes show that the PD controller, viscoelastic foundation, slenderness factor (L/R), external voltage, and GPL's weight fraction have a considerable impact on the amplitude and vibration behavior of a GPLRC smart cylindrical shell. As an applicable result in related industries, the parameter and consideration of the PD controller have a positive effect on the static and dynamic behaviors of the structure subjected to an external load. • Smart control and vibration analysis of a GPLRC structure covered with PLSA and under mechanical shock in the framework of GDQM are studied for the first time. • The external voltage is applied to sensor layer and a PD controller is used for sensor output control. • There is a good agreement between the results of semi-numerical method and FEM package. • The results show that PD controller, mechanical loading, applied voltage and weight fraction of GPL have significant influence on the amplitude, and frequency characteristics of a smart GPLRC cylindrical shell. [ABSTRACT FROM AUTHOR]