This master’s thesis investigates the propagationof underwater planar shock waves generatedby electrical explosions, triggered by the electrical dischargeof a pulsed power generator with a capacitorcharged to 23kV, through thin copper foils of 10 and18μm in thickness. The focus is on simulating andunderstanding the high-energy plasma explosion andits interaction with the fluid.A pre-existing 1D magnetohydrodynamic MHD codeoriginally developed for underwater electrical wireexplosions is adapted to simulate the electrical explosionof thin copper. The numerical model couplesthree distinct solvers: an electrical circuit submodeltracking the pulsed PPG discharge, a 0-D MHD foilsubmodel governing mass and energy conservation viaJoule heating, and a 1-D fluid solver utilizing an artificiallyupstream flux vector splitting scheme to capturethe water domain dynamics. To maximize simulationaccuracy was explored the approach of implementingexperimental voltage and current waveforms.Physical and numerical challenges regarding massconservation in the thermodynamic properties of theexpanding foil and spurious oscillations in the waterdomain are addressed. These artifacts, repectivelydriven by simple time integration schemes and by thesharp changes due to the shock front, are successfullyresolved by implementing a predictor-correctorintegration scheme for the foil density and adopting alocalized artificial viscosity window synchronized witha shock-capturing function.Finally, the numerical results are validated againstexperimental data, demonstrating strong agreementin shock front trajectories and pressure fields.