  The interaction of a high velocity clump of gas has been described by the
plasmon model, which considers balance between ram pressure and the internal
stratified structure of the decelerated clump. In this paper we propose an
analytical model to describe the mass loss of such a clump due the interaction
with the environment, describing its influence on the plasmon dynamics. We
carry out comparisons between an analytic model and axisymetric gasdynamic
simulations of plasmon evolution. From our simulations we were able to find the
values of the friction constants $\alpha$ and $\lambda$. Comparing with the
complete analytic model from which we can infer the position and the mass loss
of the clump as function of the clump's density and the environment ratio.
