# BDD & PD: TemperatureIncrease

This diagram shows the Block `TemperatureIncrease` with a supporting ConstraintBlock `TemperatureIncreaseConstraint`:
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Time for some basic thermo and some dimensional analysis:
``````
{increase=energy/(specificHeat*waterVolume)}
``````

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.

Notes
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