Kong's conventional indirect ring under crosswind: the air flow of an indirect ring wants the same k = 0.5
Tier 3: CFD, co-simulation or another model.
System: Indirect dry cooling, natural draft, vertical bundles
- What was compared
- The total air mass flow rate, relative to its windless value, of a conventional indirect natural-draft dry cooling system (a 170 m tower, 180 cooling deltas on a 159 m ring and a closed water loop through a surface condenser) at crosswinds of 4 to 20 m/s.
- Against
- The CFD study of Kong et al. (2017, Tables 1 and 2, Eqs. 2 and 5, Fig. 17), digitised; another model and not a measurement.
- The agreement
- Windless, the air mass flow rate is 47 492 kg/s against 49 668 kg/s (−4.4%). With Kröger's crosswind coefficients as printed, the flow ratio is 1.7 points high at 4 m/s and 12.0, 18.6, 32.8 and 41.7 points low at 8, 12, 16 and 20 m/s; a multiplier of 0.470 on the inlet and outlet pressure coefficients reproduces the 4 to 12 m/s range to an RMS of 4.4 points.
- What it shows
- The fitted multiplier of 0.470 supports the model's default multiplier of 0.5 on the wind pressure coefficients of a vertical ring, set on four direct-tower series, for an indirect ring. The recovery of the air flow above 12 m/s in the CFD is not reproduced, and a CFD reference gives the method no model-form accuracy.
- Source
- Y. Kong, W. Wang, Z. Zuo, L. Yang, X. Du, Y. Yang, 'Combined air-cooled condenser layout with in tube condensation and bilateral heat exchanger arrangement for natural draft dry cooling system', International Journal of Thermal Sciences 112 (2017) 318-334Tables 1 and 2 (geometry, design conditions), Eqs. (2) and (5) (the radiator polynomials), section 2.4 (wind profile, exponent 0.2 at 10 m), Fig. 17 (CNDDCS air mass flow against wind)