In this paper the main outcomes of the ”P2M Simulation Exercise on past fuel melting irradiation experiments” are provided. In the frame of the OECD-NEA-FIDES network, the P2M project (Power To Melt and Maneuverability) was launched in 2021 by CEA, EDF and SCK·CEN to study partial centerline fuel melting in un-failed instrumented PWR rods during staircase power ramps, foreseen in the BR2 experimental reactor (Belgium). The Simulation Exercise was intended to help calibrating fuel performance codes towards fuel melting and consequently better define the P2M ramps. In this frame, two past power ramps with fuel melting were simulated: the staircase ramp xM3 (R2 reactor, Studsvik, 2005) and the fast ramp HBC4 (BR2 reactor, Belgium, 1987). xM3 was performed on a MHI large grain UO2 fuel with a Zirlo cladding, pre-irradiated to an average burnup of 27 GWd.t^-1. The transient led to a maximum power of 70 kW.m^-1. HBC4 was performed on a UO2 fuel with Zy-4 cladding having an average burnup of 48 GWd.t^-1, 61 GWd.t^-1 at Peak Pellet Node. It was ramped to a maximum power of 66 kW.m^-1. xM3 kept its integrity while HBC4 cladding failed during the experiment. Extended PIE were performed in both cases.