## Calculate or Estimate the Heat Transfer Coefficient of Condensing Butane

## Calculate or Estimate the Heat Transfer Coefficient of Condensing Butane

(OP)

Where can I find, or calculate, this value? Looking for Btu/(hr ft2 °F).

Is there any other information I need to provide to help locate this value?

Thanks!!

-m

Is there any other information I need to provide to help locate this value?

Thanks!!

-m

## RE: Calculate or Estimate the Heat Transfer Coefficient of Condensing Butane

Good luck,

Latexman

To a ChE, the glass is always full - 1/2 air and 1/2 water.

## RE: Calculate or Estimate the Heat Transfer Coefficient of Condensing Butane

I'll check Perry's here on my desk but I'll be honest, I'm not good with this book. I never seem to be able to find the right section for what I'm looking for, heh.

edit:Table 3-222 gives values for saturated normal butane, kf has units of W/(m K). That's thermal conductivity, not U.## RE: Calculate or Estimate the Heat Transfer Coefficient of Condensing Butane

Approximate Coefficients for Pipe Line Losses*

(Based on Outside Pipe Area)

Temperature Difference °C

30 55 85 110 140 165 195 220 250 280 305 335

Calm Air 2.5 2.7 3 3.3 3.7 4 4.5 5 5.6 6.1 6.7 7.3

Windy Day 5 5.4 6 6.6 7.4 8 9 10 11 12 13 14

Rainy Day 12 13 15 16 18 20 23 25 28 30 32 35

Insulated 0.5 0.54 0.6 0.66 0.74 0.8 0.9 1 1.1 1.2 1.3 1.4

U-*Overall Heat Transfer Coefficients Btu/hr-sq ft-ºF

Good luck,

Latexman

To a ChE, the glass is always full - 1/2 air and 1/2 water.

## RE: Calculate or Estimate the Heat Transfer Coefficient of Condensing Butane

verylow, ~5 Btu/hr-ft2-F. Inside the pipe, the condensing coefficient is relatively high (~200-300), but that's effectively negated by the very poor rate of heat transfer through the insulation and to the air.For quick estimation purposes, I'd use an overall U of say 5, and I think that's probably on the generous side. For a more accurate estimate, do the U calculation, including the specific resistance for your insulation.

## RE: Calculate or Estimate the Heat Transfer Coefficient of Condensing Butane

Latexman, as always you are very helpful, thank you for taking the time out of your schedule to help me with my questions.

It appears there's an opportunity within this organization to build something that will help other engineers in the future, and at least automate things bit for repeated calculations. Once I build this, is this forum an appropriate place to post and ask for validation and/or review? Or would that be inappropriate?