The present work is aimed at studying, by means of a theoretical-computational approach, the frost formation on parallel-plate channels. A mathematical model to predict the frost growth and densification under supersaturated air-frost interface conditions was devised through the first-principles of mass, energy and momentum conservation. A semi-empirical correlation was additionally adopted to predict the time evolution of the frost porosity. The model predictions were compared with experimental data obtained in-house, when it was found that the model predictions for the frost thickness showed satisfactory agreement with the experimental data, with most errors falling within the uncertainties thresholds. (C) 2014 Elsevier Ltd. All rights reserved.