A new two-dimensional computer model for simulating power and pressure pulses in aqueous fissile solutions has been developed. This model includes a radiolytic gas production model that tracks the number of gas bubbles produced during an excursion. An equation of state has been developed that accounts for the production of inertial pressure due to a lag in thermal expansion and the creation of radiolytic gas bubbles. In addition, a study of various reactivity feedback mechanisms occurring during nuclear bursts has been made. The model’s predicted power and pressure pulses are compared with data from the KEWB and SILENE solution pulsed reactor experiments and have produced results that closely match the experimental data and that exhibit the main features of the experimental power and pressure traces.