قارن الطرق

	فرق درجات الحرارة اللوغاريتمي المتوسط (LMTD)	طريقة الفعالية-NTU
المجال	الديناميكا الحرارية	الديناميكا الحرارية
العائلة	Process / pipeline	Process / pipeline
سنة النشأة	1950	1984
صاحب الطريقة	Donald Kern	William Kays and Alvin London
النوع	Heat transfer correlation	Heat transfer correlation
المصدر التأسيسي	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
الأسماء البديلة	LMTD, logarithmic mean temperature difference	epsilon-NTU method, effectiveness method
ذات صلة	3	3
الملخص	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.