  We present numerical simulations for modelling optoacoustic (OA) signals
observed in PVA hydrogel tissue phantoms. We review the computational approach
to model the underlying mechanisms, i.e. optical absorption of laser energy and
acoustic propagation of mechanical stress, geared towards experiments that
involve absorbing media only. We apply the numerical procedure to model signals
observed in the acoustic near- and farfield in both, forward and backward
detection mode, in PVA hydrogel tissue phantoms (i.e. an elastic solid).
Further, we illustrate the computational approach by modeling OA signal for
several experiments on dye solution (i.e. a liquid) reported in the literature,
and benchmark the research code by comparing our fully 3D procedure to limiting
cases described in terms of effectively 1D approaches.
