In this note, the simple slip model for the Poiseuille number is completely compared with available data from Tamayol and Hooman [1] to prevent confusion. It is pointed out that the model may not be completely reflected in Ref. [1]. It is shown that the markedly simple model is relatively accurate for the practical engineering application.
In a recent paper, Tamayol and Hooman [1] studied slip flow in regular polygonal, rectangular, and rhombic ducts by eigenfunction expansion and boundary collocation. The insight provided by the authors is appreciated. The boundary collocation approach [2,3] is general, applicable to many irregular shapes although the procedures are relatively involved. Tamayol and Hooman [1] presented the valuable comparison between their data and the model proposed by Duan and Muzychka [4]. It is invaluable to validate the proposed general models with...