In this work we present a new approach for coupled CFDOptics problems that consists of a combination of a Finite Element Method (FEM) based ow solver with a ray tracing based tool for optic forces that are induced by a laser. This is a setup that is mainly encountered in the eld of optical traps. We combined the open-source computational uid dynamics (CFD) package FEATFLOW with the ray tracing software of the LAT-RUB with this task in mind. We benchmark and analyze the solver rst based on a con guration with a single spherical particle that is subjected to the laser forces of an optical trap. The setup is based on an experiment which is then compared to the results of our combined CFD-Optics solver. As an extension of the standard procedure to simulate such problems we present a method with a timestepping scheme that contains a macro step approach. The results show that this macro time-stepping scheme provides a signi cant acceleration of the standard procedure while still maintaining good accuracy. A second con guration is analyzed that involves non-spherical geometries such as micro rotors. We describe a procedure that is able to e ciently and accurately calculate optical forces with surface triangulations as input geometries. Then we proceed to compare simulation results of the nal angular velocity of the micro rotor with experimental measurements.
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