Understand that a smaller cross-section forces the same volume flow through at a higher velocity (continuity), and that a higher velocity means lower pressure (Bernoulli).
Upstream Pressure
200.0 kPaDownstream Pressure
181.0 kPaPressure Drop
18998 PaContinuity: A₁v₁ = A₂v₂ = QBernoulli (horizontal): P₁ + ½ρv₁² = P₂ + ½ρv₂²A = π(d/2)²Set the downstream diameter to about half of the upstream diameter (0.1 m or less). Confirm the downstream velocity is clearly faster than the upstream velocity.
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