Observations of coronal loops have revealed ubiquitous transverse velocity perturbations and estimates have shown that these perturbations carry a significant amount of energy, possibly sufficient to sustain the million degree solar corona.
More recently, a clear power spectrum for these transverse oscillations has been identified providing clear indication of how much energy can be extracted from propagating waves.
At the same time, MHD models still do not explain how this energy can be efficiently converted and the indications coming from the models suggest that the direct dissipation of waves is not a sufficiently efficient mechanism to heat the solar corona.
The damping of transverse waves can be understood in terms of coupling of the transversal modes (kink) with azimuthal modes (Alfvén) in the inhomogeneous boundaries of the loops, which is also the region where the energy conversion is most efficient. In this work we investigate the role of the density structure of the loop, i.e. the region with density enhancement, in the efficiency of the wave heating mechanism. Using 3D non-ideal MHD simulation with a driver that simulates the observed power spectrum of transverse waves, we focus on two different loop structure; a traditional cylindrical one where a dense interior region exists along the whole loop length and another one where there is no interior region and the density enhancement extends only until a certain length along the loop.