What do you mean by surging in compressor?
What do you mean by surging in compressor?
Compressor surge is a form of aerodynamic instability in axial compressors or centrifugal compressors. The term describes violent air flow oscillating in the axial direction of a compressor, which indicates the axial component of fluid velocity varies periodically and may even become negative.
What causes surging in compressors?
Surge is a condition that occurs in compressors when the amount of gas they are trying to compress is insufficient for the size of the compressor and the blades lose their ability to transfer energy from the shaft to the fluid, causing a reverse flow of the gas.
What is surging and choking?
Surge is a violent flow reversal that occurs when the process restricts the compressor flow below a certain minimum value. Choke occurs when the process does not create enough restriction to the compressor flow and the compressor operates at its maximum flow for a given performance level.
What is surging in compressors and how it can be prevented?
Surge instability strongly limits the operating range of turbo-compressors. Surge prevention, based on the use of an active anti-surge valve, is one way to battle the surge and other instabilities at low-flow operations. This definition can allow for a quantitative approach to surge in a turbo-compressor.
What is stall and surge in axial flow compressors?
Compressor surge In the words of compressor expert Ivor Day, stall is a disturbance of compressor flow in the tangential direction, while surge is a disturbance in the axial direction.
What is the surge line?
The boundary between the gas turbine operating region and the region where the compressor surge is certain.
How do you detect a compressor surge?
Generally, the occurrence of surge is inferred from a rapid change in any measurement that is a direct function of compressor flow or head. As mentioned previously, compressor flow, discharge pressure, and inlet temperature are signals that can be used for surge detection.
What is the difference between compressor stall and surge?
Compressor surge Rotating stall can morph into the extreme case of a compressor performance failure called surge. In the words of compressor expert Ivor Day, stall is a disturbance of compressor flow in the tangential direction, while surge is a disturbance in the axial direction.
What is stalling surging and choking in compressor?
The choking occurs in the compressor which operates at a low discharge pressure and maximum flow rate. Surge – Occur minimum flow rate, choking – at maximum flow rate. Stall – Localized fluid separation, Surge – complete fluid separation.
How do I stop my compressor stall and surge?
Preventing stall, surge Then engine control systems, such as Fadec (Full-Authority Digital Electric Control), are programmed to keep the operating point of the compressor well away from the so-called stall or surge lines.
How do stalling and surging take place in centrifugal compressor stages?
An unstable flow originates at the impeller middle-rear region and a high-frequency stall wave occurs firstly in the impeller during mild surge. Then the flow disturbance propagates downstream, and a high-frequency stall occurs in the diffuser prior to a deep surge.
How do you stop a compressor surging?
6 Ways to to Avoid Centrifugal Compressor Surge
- Larger Anti-surge Valve (ASV) Size with a Quick Opening Valve.
- Suction and Discharge Pipe Re-Routing.
- Re-Positioning Anti-surge Tap off- Point.
- Slowing Compressor Speed during Coast down.
- Discharge Side Gas Flaring.
- Hot Gas Recycle Valve Installation.
What is meant by surging in compressors?
Surge is a complete breakdown of steady flow through the compressor. It is defined as the lower limit of stable operation of the compressor. The course of the surge is decreasing mass flow rate and increases a rotational speed of the impeller.
What causes surging in a centrifugal compressor?
Compressor surge occurs when the pressure of air delivered by the compressor is higher than the pressure that the compressor can maintain. A turbocharger is a centrifugal compressor that increases air flow, which produces more horsepower. Because surging occurs when the turbocharger is producing too much air flow,…
What causes Surge in a compressor?
What Causes Compressor Surge? Driver failure, Misdistribution of load in the compressor Power failure, Restrictions in the inlet and outlet of the system Upset process conditions, Inadvertent loss of speed Startup & shutdown problems, Failure of anti-surge mechanisms, Check valve failure, Very high rotation speed and insufficient flow
What is surging and choking in centrifugal compressor?
Choking: There is an unstable limit of operation of Centrifugal and axial flow compression,known as surging.surging is caused due to unsteady,periodic and reversal of flow through the compressor,when the compressor has to operate at less mass flow rate than a predetermined value.
