Warming Milk
Ryan DymockNathan Albrechtsen
Purpose
When Samantha is hungry, she wants milk NOW!!
Doctors claim that breast milk should not be warmed in the microwave to preserve nutritional value
There are also theories that microwaves create “hot spots” that can burn Samantha’s mouth
How fast can we warm Samantha’s milk with hot water?
Model - Cylinder
.05m
.076m
Measurement
Prediction
)*(^inf)(inf)( KteTToTtT )**/()*( CpVAshK
p = 997 kg/(m^3)Cp = 4179 j/kgh = 450 W/m^2As = .012m^2V = 1.7e-4m^3
To = 290 KTinf = 368 K
*Note: Although Bi >> 0.1, lumped capacitance yields accurate results
Results
275
280
285
290
295
300
305
310
315
0 5 10 15 20 25 30 35 40
Time (s)
Tem
p (K
)
Measured Temp (K)
Predicted Temp (K)
Conclusions
Sometimes Lumped Capacitance Model still yields very accurate results when Bi > 0.1
Samantha’s milk can be warmed from the fridge in less than one minute if it is submerged in boiling water