On 3d dynamic control of secondary cooling in continuous casting process.
On FEM solution for 3D continuous casting problem
On the controllability under constraints on the control for hyperbolic equations.
Optimization approaches to some problems of building design
Advanced building design is a rather new interdisciplinary research branch, combining knowledge from physics, engineering, art and social science; its support from both theoretical and computational mathematics is needed. This paper shows an example of such collaboration, introducing a model problem of optimal heating in a low-energy house. Since all particular function values, needed for optimization are obtained as numerical solutions of an initial and boundary value problem for a sparse system...
Optimization of plunger cavity
In the contribution we present a problem of shape optimization of the cooling cavity of a plunger that is used in the forming process in the glass in dustry. A rotationally symmetric system of the mould, the glass piece, the plunger and the plunger cavity is considered. The state problem is given as a stationary heat conduction process. The system includes a heat source representing the glass piece that is cooled from inside by water flowing through the plunger cavity and from outside by the environment surrounding...
Sampled weighted attraction control of distributed thermal scan welding
This article addresses the problem of distributed-parameter control for a class of infinite-dimensional manufacturing processes with scanned thermal actuation, such as scan welding. This new process is implemented on a robotic GTAW laboratory setup with infrared pyrometry, and simulated by a flexible numerical computation program. An analytical linearized model, based on convolution of Green’s fields, is expressed in multivariable state-space form, with its time-variant parameters identified in-process....
Scalings in homogenisation of reaction, diffusion and interfacial exchange in a two-phase medium
Second-order sufficient optimality conditions for a semilinear optimal control problem with nonlocal radiation interface conditions
We consider a control constrained optimal control problem governed by a semilinear elliptic equation with nonlocal interface conditions. These conditions occur during the modeling of diffuse-gray conductive-radiative heat transfer. After stating first-order necessary conditions, second-order sufficient conditions are derived that account for strongly active sets. These conditions ensure local optimality in an Ls-neighborhood of a reference function whereby the underlying analysis allows...
Simulation of anisotropic motion by mean curvature -- comparison of phase field and sharp interface approaches.
Simulation of incompressible flows with heat and mass transfer using parallel finite element method.
Solution of temperature distribution in a radiating fin using homotopy perturbation method.
Solution of the porous media equation by a compact finite difference method.
Solving heat and wave-like equations using He's polynomials.
Solving of heat shock on a hybrid system
Spectral Numerical Study of a Problem Governed by Navier-Stokes Equations, Influence of Rayleigh and Prandtl Numbers
We present in this work a numerical study of a problem governed by Navier-Stokes equations and heat equation. The mathematical problem under consideration is obtained by modelling the natural convection of an incompressible fluid, in laminar flow between two horizontal concentric coaxial cylinders, the temperature of the inner cylinder is supposed to be greater than the outer one. The numerical simulation of the flow is carried out by collocation-Legendre...
Stability and convergence of two discrete schemes for a degenerate solutal non-isothermal phase-field model
We analyze two numerical schemes of Euler type in time and C0 finite-element type with -approximation in space for solving a phase-field model of a binary alloy with thermal properties. This model is written as a highly non-linear parabolic system with three unknowns: phase-field, solute concentration and temperature, where the diffusion for the temperature and solute concentration may degenerate. The first scheme is nonlinear, unconditionally stable and convergent. The other scheme is linear...
Steady-state solution of the PTC thermistor problem using a quadratic spline finite element method.
The heat radiation problem: three-dimensional analysis for arbitrary enclosure geometries.
Thermal radiation and buoyancy effects on heat and mass transfer over a semi-infinite stretching surface with suction and blowing.
Using explicit schemes for control problems in continuous casting process.