In the present work, we study the production of five vowels of French. The idea is to compare 2-dimensional models with 3-dimensional models, and examine whether the 2-dimensional articula-tory models can adequately describe the acoustics of the vocal tract. For the purposes of our experiments , we used 3-dimensional MRI data to acquire the shape of the vocal tract. We then use it to simulate how the pressure wave produced from the vocal folds propagates with the K-wave Matlab toolkit. We carried out acoustic simulations for both the 3-dimensional and the 2-dimensional (mid-sagittal plane) shapes of the vocal tract and compared for-mant frequencies with those calculated from the de-noised speech signal recorded in the MRI machine. We then compared the results of the 2-dimensional and 3-dimensional acoustic simulation with those provided by the traditional simulation used in ar-ticulatory synthesis, which relies on the plane wave propagation assumption.