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1. Flow calculations. Flow calculations. Dynamic pressure Pressure drop Bernoulli's equation Fan curves. Åke Mälhammar Frigus Primore malhammar.ake@wanadoo.fr. Bernoulli's equation 1. 2. Dynamic pressure. Bernoulli's equation. Total pressure. Bernoulli's equation 2. 3.
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1 Flow calculations Flow calculations • Dynamic pressure • Pressure drop • Bernoulli's equation • Fan curves Åke Mälhammar Frigus Primore malhammar.ake@wanadoo.fr
Bernoulli's equation 1 2 Dynamic pressure Bernoulli's equation Total pressure
Pressure losses 4 Head loss Friction Friction Head loss (laminar, circular pipes) (turbulent, circular pipes)
Expansion 5 A1 A2 f F<15o
Contracting jets 6 A1,w1 A2 A3, w3
Fan curves 7 Pressure System curve Fan curve Flow
Electronic devices Head loss 8
Flow distribution 1 9 Path Friction only Dynamic only p p Z-path p p U-path
Flow distribution 2 Risk for non uniform distribution.Make sure D is sufficiently large. Uniform distribution but risk forrecirculation of outlet into inlet 10 D D
Flow distribution 3 Risk for non uniform distribution. Add a honey comb structure, a dense net or increase the measure D. 11 D