Abstract

A reference implementation of a new method in isogeometric analysis (IGA) is presented. It delivers lowcost variable-scale approximations (surrogates) of the matrices which IGA conventionally requires to be computed by element-scale quadrature. To generate surrogate matrices, quadrature must only be performed on a fraction of the elements in the computational domain. In this way, quadrature determines only a subset of the entries in the final matrix. The remaining matrix entries are computed by a simple B-spline interpolation procedure. We present the modifications and extensions required for a reference implementation in the open-source IGA software library GeoPDEs. The exposition is fashioned to help facilitate similar modifications in other contemporary software libraries. Method name: Surrogate matrix method for isogeometric analysis

Abstract

One of the larger growing fields within additive manufacturing is the selective laser sintering process of semi-crystalline polymer powders. The powder is locally fused at certain areas, due to the energy output of a laser. This method allows for rapid production of complex parts, which are well suited for prototyping. The overall accuracy and stability of the process along with part properties are highly related to the process parameter. A better control of these parameters will therefore optimize the process even further. The current paper propos a numerical modelling approach and the model makes it possible, to analyze the influence of the laser-related input parameters concerning the temperature distribution and size of the melt pool. For the validation, certain outputs from the model are compared to the ones found from experimental single-line track data, where the melt pool geometry can be compared to the numerical measurements.