A fundamental understanding of the quench phenomenon is particularly important in the design and operation of magnets using High Temperature Superconductors because the quench propagation velocity is low due to high specific heat at high temperature. We have performed the simulations of a high-current forced-flow conductor model to assess the key quench parameters, e. g. the temperature increase of the normal zone and its propagation velocity, using the CryoSoft code THEA. The sensitivity of these results on conductor design and operation parameters was assessed with a variational analysis. Results show that the helium flow has a beneficial impact on the longitudinal propagation of the normal zone and the resulting reduction of the peak quench temperature.