nominal specific discharge rate (lph/100)

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ONEYHB
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nominal specific discharge rate (lph/100)

Post by ONEYHB »

Dripper SDR

Hello, I am registering a new dripper pipe, its nominal flow rate is 1.6 liters per hour, when I fill in the nominal specific discharge rate (lph/100) should I fill it with the nominal flow rate of the dripper which is 1.6, or should I use the real flow rate which would be 2.2 liters per hour at a pressure of 20mca, which is the pressure I will work with?

Another question is whether the nominal specific discharge rate (lph/100) influences the irricad when sizing the pipe and mammometric height?

If flow calculation type is checked, will irricad take only that into consideration, or will it take the nominal specific discharge rate (lph/100) into consideration.

Thank you very much
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jovivier
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Re: nominal specific discharge rate (lph/100)

Post by jovivier »

Typically the "Nominal Specific Discharge Rate" is based on the nominal flow rate. However if you always use a higher pressure you can adjust the SDR to suit. Note that in IRRICAD you can only specify the nominal tape inlet pressure and not the nominal pressure required at the emitters. The SDR is based on pressure at the emitters.

IRRICAD does not use the nominal SDR in any design processes (pipe sizing and analyses) but only as a guide in the Show Flow tool and Management if it is run prior to Zone Design. If Zone Design is run before management then the actual flows will be shown in the graphical management (Assign Zones to System Flows).

The "Flow Calculation Type" should always be enabled, turning this off reverts to a very old tape calculation method that is not used now-a-days, unless specifically advised.

The IRRICAD Team
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