09.02.2013 Views

WATER JET CONFERENCE - Waterjet Technology Association

WATER JET CONFERENCE - Waterjet Technology Association

WATER JET CONFERENCE - Waterjet Technology Association

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

and the pressure loss through the plumbing system is;<br />

By definition the nozzle pressure is,<br />

Substituting eqn. 4 and 7 into 1 gives;<br />

ΔP = (Q/Cv) 2<br />

175<br />

(4)<br />

P n=P p-ΔP (7)<br />

HP n = K 1*Q*P p -K l*Q 3 *Cv -2<br />

Taking the first derivative with respect to Q and setting equal to zero to find an inflection<br />

yields:<br />

Solving for optimum Q;<br />

O = K 1*P p —K1*Q 3 *Cv -2<br />

(9)<br />

Q = (P p/3) 1/2 * Cv (for max. HP) (10)<br />

Furthermore, substituting eqn 4 into eqn 9 and solving for the pressure drop gives,<br />

Jet Velocity<br />

For U in feet/sec and P in psi;<br />

ΔP = P p/3 (for max. HP) (11)<br />

1/2<br />

U = 12.186 * Pn Flow Rate<br />

For orifice diameter D in inches, P in psi, and Q in gpm;<br />

Jet Thrust<br />

For T in lbs-force, D in inches and P in psi;<br />

Q = 29.91 * D 2 * p l/2 (13)<br />

(12)<br />

T=(π/2)*D 2 *P (14)<br />

(8)

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!