Pressure Drop to Heat Transfer Coefficient Analog for a Heat Exchanger

[ramblin]

I have a finned tube in tube heat exchanger for which we can measure various global parameters - hot and cold side pressure drop, hot and cold side delta T, hot and cold side mass flow for many combinations of running condition.

I'm trying to break the data down into an accurate assessment of the hot and cold side heat transfer coefficients. One approach I'm considering is to use the Reynold's analogy between heat and momentum ie. Cf/2 = StPr^2/3.

My question is whether or not this method can be used with any real degree of certainty. The pressure drops are not great (5 psid MAX) but we should be able to get a decent idea of the coefficient of friction if we run enough points.

Is this a reasonable approach? (I've got another method but I'm wondering if the pressure drop data can be useful)

 

[vpl]

The only way I've seen dP used is as a rough indicator of flow (flow proportional to square root of change in dP). which isn't to say your method won't work. why are you trying to measure h? Patricia Lougheed

 

[CHD01]

The heat transfer coefficient is dependent upon much more than the mass flow. While your data may show a correlation, it is only because you have held other factors constant. If you wish a model that is valid for varying rates of fouling (for one example) I would not suggest what I think you are proposing. The more you learn, the less you are certain of.

 

[CHD01]

The heat transfer coefficient is dependent upon much more than the mass flow. While your data may show a correlation, it is only because you have held other factors constant. If you wish a model that is valid for varying rates of fouling (for one example) I would not suggest what I think you are proposeing. The more you learn, the less you are certain of.