Probabilistic modeling of the ambient air drying of Miscanthus

The drying of batches of Miscanthus in outdoor conditions that are sheltered from the rain was investigated by both theoretical and experimental approaches. The objective was to assess the sensitivity of the final moisture content of the batch to random fluctuations in the weather over a 90 day drying period. An empirical drying model relating the change in batch moisture content to ambient air temperature, relative humidity and wind speed was developed with data obtained from controlled experiments. Meteorological records for Cork, Ireland were examined over the period from January to April to determine the statistical structure of the random components of daily average temperature, humidity and wind speed. A Monte Carlo solution procedure was applied to the drying model to predict moisture content histories and hence the distribution in final batch moisture content as a result of weather variability. Outdoor drying trials were also conducted to validate the modeling approach. It was found that dispersion in batch final moisture levels is significant and ultimately controlled by the fluctuation in the relative humidity of the air.