<p>Achieving precise simulations of underwater explosion loads is a fundamental prerequisite for investigating the impact on underwater engineering materials and understanding both human injury and protection mechanisms. Current research primarily focuses on contact and near-field underwater explosions, with limited attention given to mid-field and far-field simulations, which continue to grapple with accuracy challenges. This study initially consolidates and contrasts various methods for simulating underwater explosions, ultimately pinpointing the most effective approach for mid- and far-field scenarios. Furthermore, following the mesh independence verification, a numerical model with a mesh size of 2&#xa0;mm was established to conduct multiple simulations of mid- and far-field underwater explosions. Evaluation metrics such as shock wave peak pressure and impulse were used to gauge the deviation between simulation results and empirical formula calculations. A quantitative analysis evaluated the impact of the water's equation of state and bulk viscosity coefficient on simulation accuracy. Results suggest that the Steinberg equation of state reproduces shock wave peak pressure and impulse in mid- and far-field underwater explosions with errors below 30%, while the SNL and NULL models are effective for predicting mid-field impulse. Moreover, adjusting the bulk viscosity coefficient substantially improves simulation accuracy. Notably, a linear viscosity coefficient between 0.03 and 0.06 yields accurate results for mid-field explosions, and a quadratic viscosity coefficient between 0.06 and 0.12 meets the accuracy criteria for far-field explosions. These insights contribute to improving solution accuracy in simulating mid-field and far-field underwater explosion scenarios.</p>