Relationship between pump frequency and pump outlet pressure
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Our company has a liquid ammonia transfer shielded pump with a flow rate of 36 m3/h and a head of 180 m. When the pump operates at 70% of its frequency, can the outlet pressure be calculated using the following formula? Given that the density of liquid ammonia is 625 kg/m3 and the inlet pressure is 0.85 MPa, the outlet pressure can be calculated as follows: P = 0.85×106 N/m2 + 625 kg/m3×9.8 N/kg×180 m×70% = 1621750 N/m2 ≈ 1.62 MPa. Is this calculation valid? Is there a linear relationship between the pump frequency and the outlet pressure? Please help me figure this out.
This is incorrect; the pump head is proportional to the square of the rotational speed. P=0.85×106 N/m2 + 625 kg/m3 × 9.8 N/kg × 180 m × 70% × 70% = 1390225 N/m2 ≈ 1.39 MPa
Thank you to this brother for his help:handshake
Thank you:handshake
What is 106 N/m2? How did it get here?
10 to the 6th power, superscript not available
It can’t be calculated this way; it is recommended to check the performance curve provided by the manufacturer
The impeller nowadays is of a three-element design