  We present a cosmological model constituted by three perfect fluids, cold
dark matter, vacuum energy and radiation, which interacting with each other
lead to an equivalent model of three self-preserved fluids that can be
identified with the $ \Lambda$CDM model plus a warm dark matter component. The
effective energy densities expressed in terms of the global density of energy,
its derivatives and interactions, with parameters adjusted with the
observational data allow to show the evolution of the vacuum energy. This
supports the difference in 120 orders of magnitude of the so-called problem of
the cosmological constant and at the same time the strict limits on its density
parameter at early times. The best fits parameters of the model, $ H_0= 74.06
$km/sMpc and $q_0=-0.78$, $z_{acc}=0.75$ are concordant with the bibliography
and also allow the so-called problems of coincidence and the crisis of age to
be alleviated. A geometric analysis performed with statefinders shows the
difference with the $\Lambda$CDM model because of the evolution of the
effective vacuum density of energy.
