Heat Removal from a Human Eye for Different Environmental Conditions - A CFD Study Using a Full-Scale Manikin

Abstract

Abstract The eye is an important organ of the human body, and its physiology can change mainly due to the ambient air temperature and velocity. In this study, a three-dimensional computational model for airflow around a full-scale manikin and the flow inside the eye is developed and used to evaluate the heat removal from the manikin eyes due to natural and forced convection under different environmental conditions. For natural convection, it was assumed that the movement of surrounding air was only due to the buoyancy effect in the body's thermal plume. Uniform air velocity and temperature far from the manikin were assumed for combined natural and forced convection. For simulating the velocity and temperature distribution, equations of continuity, momentum, energy, and turbulence transport model were solved numerically. The results for specific conditions were compared with the available experimental data reported in the literature and acceptable agreement was found. The validated computation model was used for several simulations of wind velocities and air temperatures. It was found that the eye surface temperature distribution predicted by the present model is closer to the experimental data than the earlier numerical studies for detached eyeballs using a constant convective heat transfer coefficient. The present results showed that the convective heat transfer coefficient over an eye surface depends strongly on the airflow velocity and temperature near the head.