Constant Flux Calorimetry

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A key part of Reaction Calorimetry is the ability to control temperature in the face of extreme thermal events. Once the temperature is able to be controlled measurement of a variety of parameters can allow an understanding of how much heat is being released of absorbed by a reaction.

In essence COFLUX or Constant flux calorimetry is a highly developed temperature control mechanism which can be used to generate highly accurate calorimetry. It works by controlling the jacket area of a controlled lab reactor, while keeping the inlet temperature of the thermal fluid constant. This allows the temperature to be precisely controlled even under strongly exothermic or endothermic events as additional cooling is always available by simply increasing the area over which the heat is being exchanged.

This system is generally more accurate than heat balance calorimetry (on which it's based) as changes in the delta temperature (T_out - T_in) are magnified by keeping the fluid flow as low as possible.

1 Theory of COFLUX
2 Specific applications of COFLUX
3 See also
4 External links

[edit] Theory of COFLUX

One of the main advantages of COFLUX calorimetry is the ability to dynamically measure heat transfer coefficient (U). We know from the heat balance equation that:

Q = m_f.Cp_f.T_in - T_out

We also know that from the heat flow equation that

Q = U.A.LMTD

We can therefore rearrange this such that

U = m_f.Cp_f.T_in - T_out /A.LMTD

This will allow us therefore to monitor U as a function of time.