In the field of computational fluid dynamics (CFD) applied on turbomachinery often integral quantities are compared between simulation and experiment. However, this does not give much information about the flow inside. In order to better validate numerical models detailed comparison of flow properties is required. Currently there are not many published methods of quantifying the quality of two- or three-dimensional simulations against measured data. The scope of this work is to implement a new comparison method which allows detailed comparison of vector fields. It is applied on multiple sets of CFD and PIV data from a centrifugal fan test bench that investigates off-design performance.