Causes Of Turbocharger Surging
- Rapid variation (reduction) in load.Reduction in load means less air intake leads back flow of savage air leads surging.For Example Bad weather – This is one of the main 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.
- Chocked exhaust and air passage like scavenge ports, valve or air cooler etc.
- Abnormal fuel system like a "unit misfiring".
- Chocked air suction filter, fouling of the turbocharger, unbalanced output from the engine, damaged exhaust valve, scavenge fire.
- 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.
- In worst cases bad condition of economizer (restrictions in exhaust gas flow) also leads surging
- Scavenge fire and Exhaust fire also may be the reason of surging
- Keep the turbocharger intake air filter clean and change it periodically
- Keep the turbine and the compressor side clean by water washing or Grid washing
- Proper maintenance and checks should be done on turbocharger periodically.
- Soot blow should be done on the regular basis in case of economizer or exhaust boiler.
- Indicator cards to be taken to assess cylinder and power distribution of individual units.
What will you do if the Turbocharger Surging happened on your watch ?
Step by step procedure given below
- Reduce the Rpm (Inform bridge & C/E if it is M/E,If it is A/E start the stand by generator and troubleshoot the affected generator)
- Check the load whether it is varying or not if it is varying try to make it study.
- Make sure that there is no fire on scavenge and exhaust side
- Check the air filter if it is dirty change it
- Do the grid washing and water washing by taking turbocharger rpm in to manufactures recommendation
brilliant
ReplyDeleteYou have given only symptoms of surge & have not indicated why a turbocharger surges. Please see the chart for axial / radial compressor characteristics & note the surge line on the left side. Surging occurs when the turbocharger operates in the surge zone. This occurs when the mass flow decreases due to causes as explained by you.
ReplyDeleteobviously surging occurs when the turbocharger operates on surge zone. Here i have explained the causes of surging
DeleteEffective...And simply explained...
ReplyDeleteglad to hear it helps u... visit again...
DeleteIt may be of interest to note that surging always occurs in the compressor stages of gas turbines, both marine & aviation, when starting up. This occurs due to sudden temperature rise on injection of fuel (to overcome inertia of the rotor) which reduces mass flow through the compressor driving the turbine. A number of devices are used to avoid surge during start up, one of which is to allow air to by pass the turbine, thus increasing air mass flow across the compressor, till the turbine achieves stable idling speed during the start process.
DeleteCan you please explain how the fouled exhaust side lead to surging? I can't somehow justify this cause. I'm appearing for class 2 and need to know. Would be grateful if you could explain.
ReplyDeleteFouling Exhaust side may keep exhaust gas in exhaust manifold longer time which means rpm of turbocharger keep it same for little bit longer time than usual after a sudden load drop....
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