Figure (b) shows the thermal evolution for a core vial subject to the three sets of parameters at T ext = -40°C. A stationary phase is observed in all cases and the values of T sp indeed correspond to those predicted; since no supercooling occurs in the case of instantaneous nucleation, no thermal spikes are observed in the corresponding profiles either. For comparison, Figure (c) presents the profiles for T ext = -8°C; as expected, the thermal evolution for the "slow" kinetics confirms that the core vials spend the entire simulated process duration in the supercooled liquid. When comparing the process duration for "fast" and "instantaneous" kinetics, one notices that the predicted values are qualitatively similar for T ext = -40°C, but differ by about a factor of three for T ext = -8°C. This clearly demonstrates the important role of stochastic nucleation on process duration, manifested for pallet freezing in the form of the stationary phase. We thus study the behavior of the process duration in more detail in section 3.4. We therefore confirm that the stationary phase stems from a balance of external cooling and heat generated by ice formation. The stochastic nature of nucleation implies that the pallet does not assume a constant temperature T sp , but that the temperature oscillates around T sp , since nucleation events release a considerable amount of heat in short time into their neighborhood. Each nucleation event leads to a local rise in temperature, and thus reduces the likelihood of nearby nucleation events, until solidification is mostly complete and the temperature decreases again. The establishment of such balance requires a certain minimum number of vials, which explains why the stationary phase was observed for neither the single vial nor the system of 2x2x2 vials.