The external characteristics of the centrifugal pump are measured, respectively, under the 6 operating conditions [0.2Q.sub.d], [0.4Q.sub.d], [0.6Q.sub.d], [0.8Q.sub.d], [1.0Q.sub.d], and [1.2Q.sub.d] (where the rated flow
[Q.sub.d] = 25 [m.sup.3]/h), and the external characteristics curves of the simulated and experimental values of the centrifugal pump before and after optimization are shown in Figure 7.
The dripper models showed performances varying in the degree of clogging and CVQ, and the dripper with rated flow
(2.30L [h.sup.-1]) was better than the others.
Pressure drop at the rated flow
rate can vary, depending on where the cooling coil is located in the system hydraulic gradient curve.
The main parameters of a hydropower station are as follows: rated head [H.sub.r] = 216 m, rated speed [n.sub.r] = 150 r/min, rated flow
[Q.sub.r] = 360.3 [m.sup.3]/s, rated power [P.sub.r] = 714 MW, the maximum of the opening [a.sub.max] = 28.5 mm (model), head loss coefficients are 0.0098 and 8.402 x [10.sup.-4], and their water flow inertia time constants are 1.3 s and 0.65 s, respectively.
But when it comes to standard air dryers, there is a "Three-100s Rule": Operating conditions should not exceed 100 psig inlet pressure, 100[degrees]F inlet temperature, or 100 percent rated flow
The fan/flowmeter used in this study has the following performance specifications: accuracy of [+ or -]3% of flow or 0.47 L/s (1 cfm), whichever is greater (using the recommended digital gage) and a rated flow
range of 4.7 to 708 L/s (10 to 1500 cfm).
Clean pressure loss at the rated flow
of 5300 cubic metre per hour is just 260Pa.
Based on this monitoring, the flow rate of the MAU was found on average to be very similar to the rated flow
rate of 1,560 L/s (3,300 cfm) at a static pressure of 250 Pa.
The rated flow
and head of the sewage immersion pump were 25[m.sup.3]/h and 15 m, respectively.
Then, according to Equation 1, the pressure drop through a HX section can be evaluated in terms of actual and rated flow
conditions according to
If speed, [N.sub.i], is below or above rated speed, output flow, [Q.sub.1] will not be at rated flow
. If [T.sub.i] < [p.sub.1]([V.sub.p]/2[pi]), the pump will be unable to meet system demands.