Conversion of exhaust volume and power of air compressor
There is a complex nonlinear relationship between the exhaust volume (volume flow) and power of an air compressor, which needs to be converted by a special formula. The following is a detailed analysis:
1. Core conversion formula
1. underlying formula
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Power (kW) calculation
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Power (horsepower/HP) calculation
2. Energy conversion efficiency formula
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Power calculation taking efficiency into account
- : Usually 0.75~0.95 (affected by air compressor type).
2. Unit conversion comparison table
| unit type | conversion relationship |
|---|---|
| power | 1 HP = 0.75 kW |
| exhaust volume | 1 m³/min = 35.3 CFM |
| pressure | 1 bar = 1.033 kgf/cm² |
| 1 MPa = 10 bar |
3. Conversion examples
Case 1: Knowing the exhaust volume and pressure, asking for power
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conditions: Exhaust volume = 2.5 m³/min, inlet pressure = 8 bar
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computing：
Case 2: Knowing the power and pressure, find the exhaust volume
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conditions: Power = 15 kW, inlet pressure = 7 bar
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computing：
4. Key influencing factors
- Compression mechanism design: There is a significant difference in efficiency between screw type and piston type (screw type is more efficient).
- pressure loss: An increase in pipe length and the number of elbows will lead to a decrease in exhaust volume.
- ambient temperature: In a high temperature environment, the air density decreases and the actual exhaust volume decreases.
- motor efficiency: Permanent magnet motors are 5% to 10% more efficient than induction motors.
5. Selection suggestions
- reserve allowance: Select the power according to the maximum air consumption ×1.2~1.5 times.
- Energy efficiency priority: Select a model with SER (specific power) ≤5.5 kW/(m³/min).
- frequency conversion adjustment: For scenarios with large fluctuations in gas volume, the inverter saves energy by more than 30%.
summary: The conversion of air compressor displacement and power needs to be combined with special formulas and working conditions. It is recommended to obtain accurate values through equipment nameplate parameters or manufacturer selection software.