Warming Milk

Ryan Dymock

Nathan 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