The identity of the fastest method changes because of the start up conditions having to be recalculated at the start of every step in a coupled ODE-hydrodynamics module.
Optimum and simple fuel management performance in the start-up condition is important for the practical deployment of PBR.
The start-up condition and extension principle of the piezoelectric element used in the vibration reduction action are designed and finalized.
Fuel management of once-through-then-out (OTTO) cycle Pebble Bed Reactors (PBR) was studied, in particular the start-up condition of the core before it achieves the equilibrium condition.
In this study, fuel composition in the start-up condition was limited to the same composition (a single enrichment) as the fuel in equilibrium condition for simplicity of the whole fuel management.
The proposed strategy is based on a structured-like population balance where uncertainties associated with the start-up condition and random fluctuations along the semi-batch operation can be taken into account in a very natural way.
The solutions obtained by this new approach are shown to agree identically with those obtained by using the Laplace transform in time only, a technique that enforces the proper start-up condition implicitly (hence, the same error cannot be committed).
We show that the reason for this is the non-rigorous enforcement of the start-up condition in the textbook approach, which leads to a violation of the principle of causality.
There is no option for fuel re-insertion in an OTTO cycle PBR, hence nuclear fuel utilization is an important factor not only in the equilibrium condition but also in the start-up condition.
An installed 900 kW fixed speed stall controlled soft-started wind turbine connected to a weak distribution grid was modeled under start-up conditions.
