The mechanical response of the constituents of fiber-reinforced composite materials is considerably distinct, the matrix showing high dependency on temperature and loading rate, not observed in the fibers. An important consequence is that the combined response becomes difficult to foresee using analytical methods, especially for complex microstructures, such as short fiber reinforced polymers. A traditional approach is to run a series of dynamic mechanical analysis (DMA) experiments, under different temperatures and loading rates, often very costly and time-consuming. A preferable alternative is the use of finite-element simulations, requiring only a geometrical representation of the microstructure and the material properties of the separate constituents. In this work, such numerical campaigns (named virtual DMAs) are modelled and simulated, for different types of microstructures and matrix / fiber combinations, to demonstrate the accuracy and viability of the approach. Results are compared with experimental results from the literature, showing good agreement.