Three dimensional heat and mass transfer in human eye based on porous medium approach

The objective of the present study is to demonstrate the effectiveness of the three-dimensional (3D) heat and mass transfer model developed by the authors to investigate the Aqueous Humour (AH) flow and thermal fields in real human eyes. The Generalised Porous Medium (GPM) approach has been implemented to reproduce both cavities and porous tissues. The 3D computational domains are reconstructed from the subject-specific 2D tomographic images of the Anterior Chamber (AC) of real eyes, by using image acquisition algorithm and modelled with AH conventional outflow pathways, comprising Trabecular Meshwork (TM), Schlemm's Canal (SC) and Collector Channels (CC). The GPM model implemented provides the flexibility to select the porosity and permeability values to model AH thermo-fluid dynamics inside both the free fluid cavities like AC, CC, SC, and the TM porous tissue. The influence of TM porous parameters on Intraocular Pressure (IOP) is discussed in detail. The TM porosity and permeability values are calibrated to obtain the pre-operative IOP of two different health conditions of the eye. The results in terms of fluid dynamics and thermal quantities, obtained with the novel 3D model and the 2D one, have been compared. A difference of 5-25% has been observed between 2D and 3D numerical results of eye models for AH velocity, skin friction coefficient (Cf) and local Nusselt number (NuL).