Figure 1.
Pictures of elephant hair on the top of the back of an Asian elephant, (A) and an African elephant’s head (B).
The presence of hair on elephants was first noted by van Leeuwenhoek [30]. Photos taken by Conor L. Myhrvold in the Woodland Park Zoo, Seattle, Washington, from outside of the elephant enclosure, with permission from the Zoo.
Table 1.
Elephant-Relevant Parameters.
Figure 2.
Schematic of our heat-transfer model showing model configuration and various parameters relating to rough and smooth skin (individual hair in small box in top-right corner is enhanced for illustrative clarity).
Figure 3.
Variation of the different heat transfer coefficients with wind speed for a hair density of 1500 hairs/m2.
(A) Heat transfer coefficient for bare smooth skin and effective heat transfer coefficient for hair over smooth skin. (B) Same as A, but for rough skin. B also depicts the alternative formulation for hrough of Yaglom and Kader [18].
Figure 4.
Increase in heat transfer due to hair, reported as a percentage hhair/hskin×100, as a function of ambient wind speed for different hair densities on smooth skin (A), and rough skin (B).
The heat transfer increase due to hair on our example elephant – which has a hair density of ∼650 hairs/m2– is ∼10% at low wind speed and decreases as the wind speed increases.