手法を比較

	対数平均温度差（LMTD）法	熱交換器の熱性能を、理論的に可能な最大熱伝達に対する比率で測定する代替アプローチであるEffectiveness-NTU法。
分野	熱力学	熱力学
系統	Process / pipeline	Process / pipeline
提唱年	1950	1984
提唱者	Donald Kern	William Kays and Alvin London
種類	Heat transfer correlation	Heat transfer correlation
原典	Kern, D. Q. (1950). Process Heat Transfer. McGraw-Hill.	Kays, W. M., & London, A. L. (1984). Compact Heat Exchangers (3rd ed.). McGraw-Hill. ISBN: 978-0070334007
別名	LMTD, logarithmic mean temperature difference	epsilon-NTU method, effectiveness method
関連	3	3
概要	The Log Mean Temperature Difference (LMTD) method is a fundamental tool for calculating heat transfer rates in heat exchangers. It defines the effective temperature difference between two fluids as the logarithmic average of the temperature differences at the inlet and outlet. This method enables engineers to size and analyze heat exchangers systematically using the basic heat transfer equation Q = U A LMTD.	The Effectiveness-NTU method is an alternative approach to heat exchanger analysis that measures thermal performance relative to the theoretical maximum possible heat transfer. It is particularly powerful for design problems where outlet temperatures are unknown. The method uses effectiveness (ratio of actual to maximum possible heat transfer) and NTU (Number of Transfer Units, a dimensionless parameter related to overall heat transfer area) to characterize heat exchanger performance.