What is Turbocharger Surging?
A turbocharger is one of the most important parts of the main propulsion system of the ship. Turbocharger surging is a phenomenon of turbocharger which affects its performance and reduces the efficiency. In this article, we will learn everything about turbocharger surging.
Turbo charger surging may be defined as a high pitch vibration of audible level coming from the blower end or compressor end of the turbocharger. Whenever the breakdown of gas flow takes place, a reversal of scavenge air takes place through diffuser and impeller blades into the blower side which causes surging. Surging is to be avoided as it interferes with the combustion in the main engine and may cause damage to the thrust bearings.
Therefore, the turbochargers are needed to be matched properly with the engine air consumption rate and pressure across the operating range of the engine and they should not fall in the surge limits.
What are the Causes of Turbocharger Surging?
The following are the causes of turbocharger surging:
- Improper power distribution between the main engine cylinders may cause turbocharger surging as one unit is producing more power and other is producing less. Due to this the air consumption required by both the turbochargers differs, which leads to surging.
- Fouled compressor on turbine side – In this case if the inlet filters are dirty then enough air can not be supplied for combustion, which leads to surging. Similarly if the turbine side is also dirty i. e nozzle, blades etc enough air can not be produced for combustion.
- Highly fouled exhaust i.e. economizer, if fitted may cause back pressure in the turbocharger and thus finally lead to surging.
- Bad weather – This is one more reason for surging. Due to bad weather the engine suddenly starts racing and sudden load change takes place. This happens because during bad weather or pitching the propeller moves in and out of the water, causing the change in load on the engine.
How to Prevent Turbocharger Surging?
The following are the ways to prevent turbocharger surging. However, it is to note that some points may vary with design and construction of the turbocharger.
- Keep the turbocharger intake filter clean.
- Water-wash the turbine and the compressor side of the turbocharger.
- Proper maintenance and checks should be done on turbocharger periodically.
- Soot blow should be done from time to time in case of economizer or exhaust boiler.
- Indicator cards to be taken to assess cylinder and power distribution of individual units.
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29 January 2013 at 18:22
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