153 research outputs found
Pricing European and American Options under Heston Model using Discontinuous Galerkin Finite Elements
This paper deals with pricing of European and American options, when the
underlying asset price follows Heston model, via the interior penalty
discontinuous Galerkin finite element method (dGFEM). The advantages of dGFEM
space discretization with Rannacher smoothing as time integrator with nonsmooth
initial and boundary conditions are illustrated for European vanilla options,
digital call and American put options. The convection dominated Heston model
for vanishing volatility is efficiently solved utilizing the adaptive dGFEM.
For fast solution of the linear complementary problem of the American options,
a projected successive over relaxation (PSOR) method is developed with the norm
preconditioned dGFEM. We show the efficiency and accuracy of dGFEM for option
pricing by conducting comparison analysis with other methods and numerical
experiments
Mixed hpâDGFEM for incompressible flows II: Geometric edge meshes
We consider the Stokes problem of incompressible fluid flow in threeâdimensional polyhedral domains discretized on hexahedral meshes with hpâdiscontinuous Galerkin finite elements of type Qk for the velocity and Qkâ1 for the pressure. We prove that these elements are infâsup stable on geometric edge meshes that are refined anisotropically and nonâquasiuniformly towards edges and corners. The discrete infâsup constant is shown to be independent of the aspect ratio of the anisotropic elements and is of O(kâ3/2) in the polynomial degree k, as in the case of conforming QkâQkâ2 approximations on the same meshe
High-Order Maximum Principle Preserving (MPP) Techniques for Solving Conservation Laws with Applications on Multiphase Flow
We develop numerical methods to solve the linear scalar conservation law fulfilling the maximum principle. To do this we use continuous and discontinuous Galerkin finite elements and achieve the preservation on the maximum principle via the Flux Corrected Transport (FCT) method. We use high-order polynomial spaces with Bernstein basis functions and obtain the optimal convergence rates with spaces of up to third order for smooth solutions that are monotone. This methodology produces good quality results for spaces up to (around) third order. However, when higher-order spaces are used non-physical oscillations are introduced, which is true nevertheless the methods are maximum principle preserving. These oscillations can be highly reduced by defining tighter bounds. Using discontinuous Galerkin finite elements we present a new FCT-like methodology based on single cell flux corrections. This method combines a mass conservative low-order Maximum Principle Preserving (MPP) solution with a non-mass conservative high-order MPP solution. The process is designed to recover mass conservation locally (with respect to degrees of freedom). Using this scheme we obtain the optimal convergence rates with spaces of up to third order for smooth solutions that are monotone. The method is designed to overcome problems when high-order spaces are used and, under this context, we obtained better results than with the standard FCT method. We present two methods to transport a smoothed Heaviside level set function using a one-stage reinitialization based on artificial compression. The first method allows arbitrarily large compression which might lead to non-physical behavior. To overcome this difficulty the second method self-balances the artificial dissipation and compression. Finally, we use the level set solver with a Navier-Stokes solver to simulate incompressible two-phase flow
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