1.7.1 Gas Turbine 9HA Air Inlet System

1.0   System Description

1.1    Main Function

The main function of the system are:

·         To remove water and dust particles from the atmosphere air sucked by the gas turbine compressor(air filter housing)

·         To covey filtered air towards the inlet plenum and to reduce gas turbine compressor noise(inlet duct and silencer).

·         To collect and distribute filtered air to the GT compressor intake.

 The inlet & exhaust system is an open loop where:

·         The air filter housing function is the removal of contaminants from the ambient air sucked by the FT compressor. Clean air is required by the combustion, the hot parts s cooling air system and to avoid corrosion, erosion and fouling of mechanical components such as compressor sand turbine blades.

·         Insects screen enables to catch big amount of insect which could clogged very quickly the pre filters stages, and so avoid frequent maintenance of pre filtration stages.

·         Inlet weather hoods and coalesce stage are used to remove water droplets. Dust Particles are removed by pre filter and high efficiency filtration cells.

·         A closing flab enables inlet system closing in case of long FT stop period to avoid very cold air circulation through compressor and Gas turbine.

·         Anti-icing protection of the inlet system components is ensured by a water/air heat exchanger. Exchanger also enables to guarantee the minimum ambient air temperature (-29 C) required at the compressor.

·         A bleeding heating manifold with acoustical nozzles dispatches air extracted from compressor in GT part load, to protect IGV stages from icing and to respect Nox level.

·         The mechanical security of the inlet system ducting and housing is insured by pressure drop monitoring which controls a GT Run Back in case of high pressure drop level reached and by implosion doors’ opening.

·         The air inlet duct system including the inlet silencer is used to convey atmospheric filtered air towards the inlet plenum. Inlet silencer enables to attenuate noise generated by the GT compressor.

·         The inlet plenum collects the atmospheric air and allow the inlet compressor feeding with a homogeneous distribution.

1.2    Components of Air intake System.

GE Code	Function
Weather Hoods	Protect filter housing against rain water from entering into the intake system.
Closing Flap	Close inlet system to avoid cold air circulation during GT stop period.
Water/Air Heat Exchanger	Operates as Anti icing system to protect filters against frost and as heater to guarantee min. required Temp. At compressor inlet.
AIBH manifold	Dispatch air extracted from GT compressor in the inlet system to cover the BH functions.
Pre filter and high efficiency stage	Remove dust particles from ambient air sucked by GT compressor.
Inlet silencer	Drive filtered ambient air towards the inlet plenum. Reduce noise coming from GT compressor.
Inlet plenum	Collect and distribute air to the GT compressor intake (IGV).