Medical & Biological Engineering & Computing

, Volume 56, Issue 10, pp 1823–1839 | Cite as

A generalised porous medium approach to study thermo-fluid dynamics in human eyes

  • Alessandro Mauro
  • Nicola Massarotti
  • Mohamed Salahudeen
  • Mario R. Romano
  • Vito Romano
  • Perumal Nithiarasu
Original Article


The present work describes the application of the generalised porous medium model to study heat and fluid flow in healthy and glaucomatous eyes of different subject specimens, considering the presence of ocular cavities and porous tissues. The 2D computational model, implemented into the open-source software OpenFOAM, has been verified against benchmark data for mixed convection in domains partially filled with a porous medium. The verified model has been employed to simulate the thermo-fluid dynamic phenomena occurring in the anterior section of four patient-specific human eyes, considering the presence of anterior chamber (AC), trabecular meshwork (TM), Schlemm’s canal (SC), and collector channels (CC). The computational domains of the eye are extracted from tomographic images. The dependence of TM porosity and permeability on intraocular pressure (IOP) has been analysed in detail, and the differences between healthy and glaucomatous eye conditions have been highlighted, proving that the different physiological conditions of patients have a significant influence on the thermo-fluid dynamic phenomena. The influence of different eye positions (supine and standing) on thermo-fluid dynamic variables has been also investigated: results are presented in terms of velocity, pressure, temperature, friction coefficient and local Nusselt number. The results clearly indicate that porosity and permeability of TM are two important parameters that affect eye pressure distribution.

Graphical abstract

Velocity contours and vectors for healthy eyes (top) and glaucomatous eyes (bottom) for standing position.


Generalised porous medium model Eye modelling Aqueous humor flow Intraocular pressure (IOP) Patient oriented Heat transfer 



Skin friction coefficient


Specific heat (J/g/K)


Darcy number


Forchheimer coefficient


Gravity (m/s2)


Thermal conductivity (W/m K)


Characteristic length (m)


Normal direction


Local Nusselt number


Pressure (Pa)


Prandtl number


Time (s)


Temperature (°C)


Velocity (m/s)

Greek symbols


Thermal diffusivity (m2/s)


Thermal expansion coefficient (1/°C)




Permeability (m2)


Viscosity (Pa s)


Density (kg/m3)


Wall shear stress (Pa)



Anterior chamber


Aqueous humor


Collector channel


Healthy eye


Glaucomatous eye


Intraocular pressure


Schlemm’s canal


Trabecular meshwork















Funding information

Alessandro Mauro, Nicola Massarotti and Mario R. Romano gratefully acknowledge the financial support of TeVR SIR project no. RBSI149484, CUP E62I15000760008. Alessandro Mauro also gratefully acknowledges the local program of the University of Napoli “Parthenope” for the support to individual research.

Compliance with ethical standards

The study was conducted according to the tenets of the Declaration of Helsinki.


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Copyright information

© International Federation for Medical and Biological Engineering 2018

Authors and Affiliations

  1. 1.Dipartimento di IngegneriaUniversità degli Studi di Napoli “Parthenope”NapoliItaly
  2. 2.Department of Biomedical SciencesHumanitas UniversityRozzano (Milan)Italy
  3. 3.Department of Eye and Vision Science, Institute of Ageing and Chronic DiseaseUniversity of LiverpoolLiverpoolUK
  4. 4.Moorfields Eye HospitalLondonUK
  5. 5.Zienkiewicz Centre for Computational Engineering, College of EngineeringSwansea UniversitySwanseaUK

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