A note on micropolar fluid flow and heat transfer over a porous shrinking sheet

The flow of micropolar fluid and heat transfer past a porous shrinking sheet is studied in this note. The main concern, unlike the recent numerical work of Bhattacharyya et al. (2012) [1], is to determine mathematically the bounds of multiple existing solutions of purely exponential kind. The presence of dual solutions are proved for the flow field, whose closed-form formulae are then derived. The energy equation is also treated analytically yielding exact solutions beneficial to understand the rate of heat transfer. Critical values for the existence or nonexistence of unique/multiple solutions are worked out. The exact form of velocity/temperature profiles and the skin friction/couple stress/heat transfer parameters enable one to easily catch the physical processes occurring in the present model.