What does the 'pump efficiency curve' indicate?

The pump efficiency curve is a critical tool in understanding how a pump performs across different operational conditions. It illustrates the relationship between the hydraulic efficiency of the pump and varying flow rates, indicating how effectively the pump converts input power (measured in horsepower or kilowatts) into hydraulic energy (flow and pressure) at those specific flow rates.

This curve is particularly valuable for operators because it helps identify the optimal operating point for the pump, allowing for the most efficient performance. By examining this curve, operators can make informed decisions regarding system design and operational adjustments, thereby maximizing energy savings and minimizing wear on the pump.

The other options lack the comprehensive insight the efficiency curve provides. For instance, while it does reflect maximum pressure capabilities, it goes far beyond that by showing how efficiency varies with flow rates. It does not directly determine the pump size needed; sizing considerations involve additional factors like system requirements and operational parameters. Lastly, the efficiency curve applies to all types of pumps, not exclusively to submersible models, making it a universal concept in pump operation analysis.