Computational fluid dynamics (CFD) is a well-established tool in the product design process. Particularly it is used to design water pumps. In general these components are simulated using steady simulations with moving reference frames. The aim of these simulations is not only optimal hydraulic parameters, but also to improve customer comfort by reducing the noise level of the single components. Pressure fluctuations are one main source of noise. These fluctuations can be computed by unsteady simulations. At present unsteady simulations are quite costly in computational resources and memory, thus alternatives are sought. The time periodic behavior of fluid machines allows a model reduction using frequency methods. Thus in this work a time domain method to efficiently compute incompressible, periodic fluid flows is investigated and implemented into the open source software OpenFOAM. First, different frequency and time domain methods are introduced and the time spectral method (TSM) is identified as a suitable approach as the method is able to solve nonlinear effects in time. Then the properties of the TSM are outlined using prototype equations instead of the more complex Navier-Stokes equations. The differences between the TSM and regular time stepping schemes are shown. Different implementations of the TSM have been developed in the past. However, most are dedicated to compressible flow and thus cannot be used to solve for incompressible flows. Thus, in the first part of this work a formulation of the TSM within a pressure-correction algorithm is derived and implementation details are shown. Different numerical solution strategies to solve the coupled system are investigated and verified using simple flow problems. It is shown that a Krylov subspace method coupling all temporal and spatial nodes is well suited for industrial problems. After the TSM has been applied to simple cases, more complex flow phenomena are computed. The flows around an oscillating blade profile, around a ship propeller and through a flutter valve are investigated. The temporal modes of the fluid flow are computed and the necessary amount of frequencies to represent the flow field is researched. Simulations using regular time stepping schemes and the TSM are performed and compared. The work concludes showing the potentials and limitations of the proposed method.weiterlesen