Paddle Flocculator Power from Geometry

P = 0.5 x Cd x rho x A x v_rel^3, the Newtonian drag. Two subtleties - the power goes as the CUBE of the relative velocity, and the water slips (rotates with the paddles) so v_rel is only (1 - k) of the tip speed; ignoring the slip roughly doubles the power. A 6-ft wheel at 3 rpm with 40 ft^2 of blade delivers ~267 W. Cd (~1.8) and slip k (~0.25) are user inputs because references disagree; the drag is exact once chosen. A design aid, not a metered power.

v_tip = 2 x pi x paddle_radius_ft x wheel_rpm / 60; v_rel = v_tip x (1 - slip_factor); power_ftlbs = 0.5 x drag_coeff x 1.937 x paddle_area_ft2 x v_rel^3; power_w = power_ftlbs x 1.35582; power_hp = power_ftlbs / 550.

Camp paddle flocculator power (water-treatment design practice), by name.

The Camp paddle-power drag relation is public water-treatment design material; the flocculator design and the operator govern.

Estimate. AHJ and licensed professional govern.

Field names used by the API: paddle_radius_ft, wheel_rpm, paddle_area_ft2, drag_coeff, slip_factor, v_rel_fps, power_ftlbs, power_w

• Cube law and slip P scales with v_rel^3, and v_rel = (1 - k) x tip speed; ignoring the slip roughly doubles the powerCamp / water-treatment design practice
• User-chosen constants Cd (about 1.8, 1.0-1.8 reported) and k (about 0.25, 0.25-0.40 reported) are inputs because the references disagreeflocculation literature