BDD & PD: TemperatureIncrease

This diagram shows the Block TemperatureIncrease with a supporting ConstraintBlock TemperatureIncreaseConstraint:
Click on the image to view it full size
Time for some basic thermo and some dimensional analysis:


Remember this loophole?

Let's see whether we can make the numbers fit anyway:

It seems that in the spec example that shonky "1mL water equals 1g" trick has been used once again.

The startup value 4180.0 for specificHeat works quite well across the expected temperature ranges if it is in J/(K⋅L), noting the following data are in J/(K⋅cm^3):

So 4180.0 J/(K⋅L) seems reasonable.

But note also that to get the dimensional analysis to work the "waterVolume" has to be a rate:

This is based in part on the observation that the consumer HeatingCalculation does NOT treat the temperature increase as a rate, together with:

Assume you've got all of the power 400 J/s from the heater (ignore any radiative loss) and plugin these values:

specificHeat -> 4.180 J/(K cm^3)
waterVolume -> 0.1 L/s
energy -> 400 J/s
L -> cm^3*1000

This gives a temperature increase of 0.956938 K. We'll see also later when we run the simulation that the assumption of waterVolume = 0.1 L/s corresponds well enough with the equivalent vapor output rate.

Up next
Snippets (quotes/extracts)
Visit also
Visit also (backlinks)
Related slides (includes other tutorials)
Related slides (backlinks, includes other tutorials)
External links