Performance curve of Roots blower
The performance curve of a Roots blower is a graph that reflects the relationship between parameters such as air volume, pressure, and shaft power. It is of great significance for selecting suitable Roots blowers and optimizing their operation. The following is a detailed introduction to the performance curve of Roots blower:
1、 Main performance parameters
The main performance parameters of Roots blower include speed, pressure, flow rate (air volume), shaft power, and exhaust temperature.
1. Speed: The speed at which the active shaft of the blower rotates per unit time, usually in r/min.
2. Pressure: The gas pressure at the inlet and outlet flanges of the blower, divided into inlet pressure and outlet pressure, commonly measured in Pa or kPa.
3. Flow rate: The mass or volume of gas passing through a specified section of a blower per unit time is called the mass flow rate or volume flow rate of gas passing through that section, commonly measured in m3/s or m3/min.
4. Shaft power: The power transmitted from the prime mover to the active shaft of the blower, commonly measured in W or kW.
2、 Performance curve type
The performance curve of Roots blower mainly includes the curve Q-P of the relationship between air volume (Q) and pressure (P) changes, as well as the curve N-P of the relationship between shaft power (N) and pressure changes.
1. Q-P curve:
At the rotational speed, when the pressure change of the Roots blower is large, the change in air volume is very small and basically remains unchanged.
This indicates that Roots blowers are particularly suitable for situations where pipe network resistance is variable and air flow requirements are basically stable.
2. N-P curve:
The shaft power increases with the increase of pressure.
This helps determine the appropriate shaft power based on the required pressure and air volume during selection, thereby avoiding excessive energy consumption.
3、 Interpretation of Performance Curve
1. Air volume selection:
Determine the required air volume based on actual needs and find the corresponding air volume value on the Q-P curve.
Note that when the pressure changes significantly, the air volume remains basically unchanged, which is an important characteristic of Roots blowers.
2. Pressure selection:
Determine the required pressure range based on actual operating conditions and find the corresponding pressure values on the Q-P and N-P curves.
Note that as the pressure increases, the shaft power also increases accordingly. Therefore, it is necessary to choose a suitable pressure range as much as possible while meeting the air volume requirements to reduce energy consumption.
3. Shaft power calculation:
Find the corresponding shaft power value on the N-P curve based on the selected air volume and pressure values.
This helps in selecting the appropriate motor and transmission device to ensure the normal operation of the Roots blower.
4、 Application examples
In practical applications, stable and efficient fan models can be selected by analyzing the performance curve of Roots blowers to meet the process requirements of reducing energy consumption and operating costs. For example, in a sewage treatment system, the appropriate model of Roots blower can be selected based on the required air volume and pressure to ensure the efficiency and effectiveness of sewage treatment.
In summary, the performance curve of a Roots blower is an important tool for reflecting its performance. By interpreting and analyzing the performance curve, it is possible to more accurately select the appropriate Roots blower model and optimize its operating parameters, thereby improving the operational efficiency of the equipment and reducing energy consumption.
