Re: [TRNSYS-users] how to fix power consumption of a pump

[David BRADLEY <d.bradley@tess-inc.com>]

Sajid,

  You'll need to look at the variable speed pump Type's parameters. Most VSP models ask for the coefficients of the polynomial that relates power consumption to flow rate. If you set that polynomial up with only one coefficient whose value is 1 then your polynomial comes down to p = pRated. If you set the number of coefficients to 4 and give the first three a value of 0 and the last one a value of 1 then your polynomial is p = pRated*(m/mRated)**3

kind regards,

 David

On 05/11/2019 13:59, MEHMOOD Sajid via TRNSYS-users wrote:

Dear Trnsys Users,

I have a question regarding Pump Pump Consumption (Variable Speed Pump). I used forcing function to control mass flow rate of pump. And plotted result shows that  mass flow rate is different in different hours of the day. But power consumption of pump is constant. Common sense says that when pump flow rate is different, power consumption by pump should be different. is not it?

Please see attached figures (plotted results).

Please give your opinion in this regard.

Thank you.

Best Regards,

Sajid

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