Transients analysis of the NPP-L V under conditions of extended power up rate using the extended operation domain

The extended operation domain of the map flow-power allows operating to an extended power with a reduced flow in the core, this implies to expand the operation frontier to allow 120% of the original licensed thermal power (OLTP), with a flow in the core so low as 80% of the nominal flow, with a high pattern of control rods. The present work has as objective to study the response to recirculation operational transients of the nuclear power plant of Laguna Verde under conditions of Extended Power Up rate (EPU) and under the extended operation domain of the map flow-power. The content of this work covers the analysis of the thermal-hydraulic uncertainties obtained of the simulation of the recirculation pumps shot, as well as of the transition of high to low speed of these pumps. Both simulations were carried out for EPU conditions (120% of OLTP and 100% of flow in the core) and for the extended operation domain of the map flow-power, (120% of OLTP and 80% of flow in the core), this because the reactor will be situated in a region of high probability of uncertainty. At the present time any plant at world level has operated under EPU conditions under the extended operation domain of the map flow-power, for what the results of this work are innovative in this field, allowing to know the responses to the presented transients, and later on to develop the operative and regulatory conditions necessary for the operation of this domain, with the purpose of guaranteeing the safety. (Author)