Determination of diffusion and convective transfer coefficients in food drying revisited: A new methodological approach

It is usual to determine diffusion and convective transfer coefficients using classical approximate relationships involving dimensionless numbers. These approximate relationships were developed in the past, in order to avoid the difficulties associated with calculations of large series expansions and its corresponding expansion coefficients given by transcendental equations. However, the development of improved computing techniques has removed these difficulties, such that currently such calculations can be easily performed. An iterative methodology is proposed that takes advantage of current computational capabilities, avoiding to use approximate relationships. The proposed methodology is applied to generated data and also to experimental data from carrot drying. Additionally, a Matlab® implementation of the proposed iterative methodology, along with the input data files corresponding to the results presented in this paper, is provided as supplementary material.