Gas labyrinth seals, widely used in steam turbine-generator sets to reduce steam leakage between casings and rotors, significantly affect the vibration stability of rotor train systems. Therefore, the modeling of gas labyrinth seals has been a major concern in the rotordynamic simulation of steam turbine-generator sets. In this paper, the empirical parameters, (m, n) in the Childs' bulk flow equations for the dynamic coefficients of gas labyrinth seals are modified to yield better results for wider application ranges. These parameters (m, n) are obtained as functions of inlet/outlet pressure differences of seals by using least square fitting to the computed results from Fluent. This study helps the user using modified bulk flow equations save computational time and implement applications quickly.