The energy transferred from the anterior chamber of the eye through the cornea varies considerably depending on whether a contact lens is worn. Treat the eye as a spherical system and assume the system to be at steady state. The convection coefficient ho is unchanged with and without the contact lens in place. The cornea and the lens cover one-third of the spherical surface area.

r₁ = 10.2 mm                           r₂ = 12.7 mm

r₃ = 16.5 mm                           T_∞.o = 21°C

T_∞.i = 37°C                              k₂ = 0.80 W/m ∙ K

k₁ = 0.35 W/m ∙ K                   ho = 6 W/m² ∙ K

hi = 12 W/m² ∙ K

(a) Construct the thermal circuits, labeling all potentials and flows for the systems excluding the contact lens and including the contact lens. Write resistance elements in terms of appropriate parameters.

(b) Determine the heat loss from the anterior chamber with and without the contact lens in place.

(c) Discuss the implication of your results.

Transcribed Image Text:

k1 Anterior chamber k2 Contact Cornea- lens