The original formula for the computation of the logarithmic mean temperature difference in finite precision floating-point arithmetic may suffer from serious round-off problems when both temperature differences are very close to each other. An alternative, mathematically equivalent, yet simple formula showing better numerical properties is presented.

Issue Section:
Technical Briefs
Keywords:
temperature distribution, floating point arithmetic, heat transfer, logarithmic mean temperature difference, LMTD, floating-point arithmetic
Topics:
Computation, Temperature
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Copyright © 2006
 by American Society of Mechanical Engineers
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