The expected chirp mass distribution of observed events for future gravitational wave detectors is extensively investigated in the presence of an exotic fluid component with an arbitrary equation of state , -1 \leq \omega _ { x } \equiv p _ { x } / \rho _ { x } < 0 , i.e. , the so-called dark energy component .
The results for a flat model dominated by a dark energy are compared to those for the standard flat model dominated by cold dark matter .
It is found that for a flat universe the chirp mass distribution shows a sensitive dependence on \omega _ { x } , which may provide an independent and robust constraint on the cosmic equation of state .