  We study the dynamics of electroweak phase transition in a simple extension
of the Standard Model where the Higgs sector is extended by adding an
$SU(2)_L$-triplet with hypercharge Y=2. By making random scans over the
parameters of the model, we show that there are regions consistent with
constraints from collider experiments and the requirement for a strong
first-order electroweak phase transition which is needed for electroweak
baryogenesis. Further, we also study the power spectrum of the gravitational
waves which can be generated due to the first-order phase transitions.
Moreover, the detectability of these gravitational waves, via future
space-based detectors, is discussed.
