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Heat loss by conduction: Q

Cooling "resistance"
 

Core temperature drop after 100 s

= k A (Tc Ta)/d

= heat loss required to lower Tc by 1°C
= (specific heat) x (mass)

= 100*Q/cooling resistance                                                                       

 

Heat loss model

parameters

fixed settings

deer-like

dog-like

mouse-like
A (surface area - initial value) 25000cm2 6590cm2 190cm2
mass 50000g 6000g 30g
Tc (core temperature) 37°C 37°C 37°C
specific heat 2.1j/g 2.1j/g 2.1j/g
 

variable settings

choices

effects
Ta (air temperature) range -20 – 30°C –  

d (insulation thickness)

k (thermal conductivity)

 

 skin d = 1 0.005 W/cm/°C
fat d = 2 0.005 W/cm/°C
thin fur d = 3 0.004 W/cm/°C
thick fur d = 4.5 0.004 W/cm/°C
feathers d = 3 0.0025 W/cm/°C
behaviour huddling Anew = A * 0.75  
life under snow Ta = 0°C  
fluffing feathers /erection of hairs dnew = d * 1.2  

 
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