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The validation record

Kröger Example 7.3.1

Indirect natural-draft tower, horizontal array

Tier T: a textbook worked example - a published answer, not a measurement.

System: Indirect dry cooling, natural draft, horizontal array

What was compared
The air mass flow rate, the heat transfer rate, the air and water outlet temperatures, the overall conductance, the bundle loss coefficient at oblique inflow and the temperature correction factor of an indirect natural-draft tower with a horizontal array of A-frame bundles in the inlet plane.
Against
Kröger's worked Example 7.3.1 (Kröger, Vol. 2, Section 7.3), a published calculation and not a measurement.
The agreement
The heat transfer rate is reproduced to within 0.024% and the air mass flow rate to within 0.010%, and both outlet temperatures to within 0.005 K.
What it shows
The agreement verifies that the model implements Kröger's draft equation for this tower and its water side, the ε-NTU method with the Roetzel correction factor (Kröger, Appendix B), as published. It says nothing about the method's accuracy against a measured plant.
Source
Kröger, D.G., Air-Cooled Heat Exchangers and Cooling Towers: Thermal-Flow Performance Evaluation and Design (PennWell, 2004)Vol. 2, Example 7.3.1