Three-level discrete time Galerkin approximations for the non-stationary Navier-Stokes equation
Time analyticity and backward uniqueness for the Boussinesq equations
We prove that strong solutions of the Boussinesq equations in 2D and 3D can be extended as analytic functions of complex time. As a consequence we obtain the backward uniqueness of solutions.
Time domain computational modelling of 1D arterial networks in monochorionic placentas
In this paper we outline the hyperbolic system of governing equations describing one-dimensional blood flow in arterial networks. This system is numerically discretised using a discontinuous Galerkin formulation with a spectral/ element spatial approximation. We apply the numerical model to arterial networks in the placenta. Starting with a single placenta we investigate the velocity waveform in the umbilical artery and its relationship with the distal bifurcation geometry and the terminal resistance....
Time domain computational modelling of 1D arterial networks in monochorionic placentas
In this paper we outline the hyperbolic system of governing equations describing one-dimensional blood flow in arterial networks. This system is numerically discretised using a discontinuous Galerkin formulation with a spectral/hp element spatial approximation. We apply the numerical model to arterial networks in the placenta. Starting with a single placenta we investigate the velocity waveform in the umbilical artery and its relationship with the distal bifurcation geometry and the terminal resistance....
Time domain simulation of a piano. Part 1: model description
The purpose of this study is the time domain modeling of a piano. We aim at explaining the vibratory and acoustical behavior of the piano, by taking into account the main elements that contribute to sound production. The soundboard is modeled as a bidimensional thick, orthotropic, heterogeneous, frequency dependent damped plate, using Reissner Mindlin equations. The vibroacoustics equations allow the soundboard to radiate into the surrounding air, in which we wish to compute the complete acoustical...
Time estimates for the Cauchy problem for a third-order hyperbolic equation.
Time fractional Kupershmidt equation: symmetry analysis and explicit series solution with convergence analysis
In this work, the fractional Lie symmetry method is applied for symmetry analysis of time fractional Kupershmidt equation. Using the Lie symmetry method, the symmetry generators for time fractional Kupershmidt equation are obtained with Riemann-Liouville fractional derivative. With the help of symmetry generators, the fractional partial differential equation is reduced into the fractional ordinary differential equation using Erdélyi-Kober fractional differential operator. The conservation laws are...
Time Spectral Method for Periodic and Quasi-Periodic Unsteady Computations on Unstructured Meshes
For flows with strong periodic content, time-spectral methods can be used to obtain time-accurate solutions at substantially reduced cost compared to traditional time-implicit methods which operate directly in the time domain. However, these methods are only applicable in the presence of fully periodic flows, which represents a severe restriction for many aerospace engineering problems. This paper presents an extension of the time-spectral approach...
Time-dependent coupling of Navier–Stokes and Darcy flows
A weak solution of the coupling of time-dependent incompressible Navier–Stokes equations with Darcy equations is defined. The interface conditions include the Beavers–Joseph–Saffman condition. Existence and uniqueness of the weak solution are obtained by a constructive approach. The analysis is valid for weak regularity interfaces.
Time-dependent numerical modeling of large-scale astrophysical processes: from relatively smooth flows to explosive events with extremely large discontinuities and high Mach numbers
We calculate self-consistent time-dependent models of astrophysical processes. We have developed two types of our own (magneto) hydrodynamic codes, either the operator-split, finite volume Eulerian code on a staggered grid for smooth hydrodynamic flows, or the finite volume unsplit code based on the Roe's method for explosive events with extremely large discontinuities and highly supersonic outbursts. Both the types of the codes use the second order Navier-Stokes viscosity to realistically model...
Time-dependent Stokes equations with measure data.
Tin melting: Effect of grid size and scheme on the numerical solution.
To the problem of distribution of structural components of a capillary porous medium.
Topology of 2-D incompressible flows and applications to geophysical fluid dynamics.
This article presents a survey of a new dynamical systems theory for 2D incompressible flows and its applications to geophysical fluid dynamics.
Towards robust 3D -pinch simulations: Discretization and fast solvers for magnetic diffusion in heterogeneous conductors.
Transformation of divergence theorem in dynamical fields
In this paper we will study the flux and the divergence of vector in dynamical fields, on the basis of conventional divergence definition and using the conventional method to find the vector flux. We will reveal that vector flux and divergence of vector do not vanish in dynamical fields. In terms of conventional EM field formalism, we will show the changes appearing in dynamical fields.
Transformation of Three-Dimensional Regions onto Rectangular Regions by Elliptic Systems.
Transient development of gravity waves for two layered fluids.
Transient MHD double-diffusive natural convection over a vertical surface embedded in a non-Darcy porous medium.
Transition from the chaotic turbulence to the turbulent structures.