This study investigates the generation of surface waves during shallow submarine volcanic eruptions by incorporating a Gaussian heat flux at the seabed to simulate eruption dynamics. Using the three-dimensional ocean flow model PSOM, we analyzed wave generation mechanisms under varying heat flux levels (10,000 W/m<sup>2</sup> and 20,000 W/m<sup>2</sup>) and volcanic depths. Results demonstrate that higher heat flux values and shallower eruption depths produce larger surface waves, corroborating findings from prior research. By modeling the heat flux-driven convection flows, including plume generation and water entrainment, the study highlights the critical role of thermal effects in tsunami formation. The proposed methodology enhances traditional tsunami models by accounting for heat flux impacts on vertical velocity and surface displacement. These findings provide new insights into the hazards posed by shallow submarine eruptions, improving risk assessments for coastal regions.