Mathematicians model heat flow in human tears

Mathematicians from the University of Delaware have created a new model of the fluid dynamics and heat flow in human tears. When people blink their eyes, a thin liquid film is spread across the surface of the eye.

Experiments show that the surface of the tear film cools slightly after each blink, and for dry eye patients the rate of cooling can be even higher. The Delaware researchers set out to create a model with enough detail to capture this experimentally observed cooling.

Models that set a fixed temperature for the eyeball show the temperature of the tear film actually increasing slightly after each blink. A model that incorporates heat transfer into the eye through a thin layer likewise shows a during the interblink period. But when the researchers incorporated heat transfer into a sufficiently thick region of tissue under the tear film, the model produced results comparable to the rate of cooling observed in vivo.

Future work by the team may touch on better ways to model the lipid component of tears and the temperature dynamics during the motion of a blinking eyelid.


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Drop in temperature may explain the increase in dry eye suffering

More information: "A model for the human tear film with heating from within the eye" Physics of Fluids.
Journal information: Physics of Fluids

Citation: Mathematicians model heat flow in human tears (2012, June 5) retrieved 20 September 2019 from https://phys.org/news/2012-06-mathematicians-human.html
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Jun 06, 2012
These researchers are for the most part intelligent people ... which is why I'm asking, "why in heaven's name are they wasting time and money on useless projects as this. The mathematic modeling of sweat on the human skin will have the potential of far greater pratical applications while still having provided the oppertunity for pure academic study".

Jun 06, 2012
"why in heaven's name are they wasting time and money on useless projects as this"
It's easy: because they're overemployed due the financial crisis and end of adventurous projects like the nuclear weapons or cosmic flights - and we are sufficiently silly to pay them for it. And this stupidity has no boundaries. Many researchers have both intellectual, both technical capacity to work on really useful research, like the cold fusion. But surprisingly, just this research is heavily ignored. A simple analysis would reveal, why is it so: the effective research could bring a progress into human society, but from the same reason it would decrease the job opportunity for another researchers involved in alternative, less effective methods of energy production/conversion/transport and/or storage.

In Czech we have a proverb: "Carps never empty their own pond"

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