Propagation of stochastic temperature fluctuations in refrigerated fruits

A steady state variance propagation algorithm is derived to investigate the effect of stochastic air temperature disturbances on the variability of th e temperature field inside refrigerated fruits during cold storage conditio ns. The disturbances are modelled by continuous-time autoregressive process es of variable order. The algorithm is based on the finite element formulat ion of the heat conduction equation and involves the numerical solution of matrix equations of the Lyapunov and Sylvester type. As an example, the col d storage of pineapple has been considered. It is shown that disturbances o f different order but with the same scale of fluctuation result in comparab le centre temperature variances. (C) 1999 Elsevier Science Ltd and IIR. All rights reserved.