Modelling of Arbitrary Shaped Channels and Obstacles by Distance Function

Numerical simulation is a tool used in multiple scientific domains. There is a wide range of simulations where we model a flow of fluid in a specific geometry, for example in simulations of blood flow in microfluidic channels. In such cases, a complex shape of channels has to be defined by describing its boundaries and rigid obstacles. The purpose of this study is develop a method of defining boundaries and obstacle objects with complex and non-trivial shapes in such numerical simulations. The obstacle or a boundary needs to be described only by a cloud of points defining its surface. Based on this point cloud a distance function determining the position and the shape of the obstacle is defined in the whole simulation domain. This general method is presented on a concrete examples involving several simulations performed within a simulation package ESPResSo. The new method of obstacle creation gives excellent results in terms of the accuracy and simulation time consumption.