  Non-ideal fluid dynamics with cylindrical symmetry in transverse direction
and longitudinal scaling flow is employed to simulate the space-time evolution
of the quark-gluon plasma produced in heavy-ion collisions at RHIC energies.
The dynamical expansion is studied as a function of initial energy density and
initial time. A causal theory of dissipative fluid dynamics is used instead of
the standard theories which are acausal. We compute the parton momentum spectra
and HBT radii from two-particle correlation functions. We find that, in
non-ideal fluid dynamics, the reduction of the longitudinal pressure due to
viscous effects leads to an increase of transverse flow and a decrease of the
ratio $R_{out}/R_{side}$ as compared to the ideal fluid approximation.
