UNDERSTANDING THE NOISE GENERATION MECHANISMS OF INDUSTRIAL COMBUSTION TURBINES AND DESIGNINGEFFECTIVE NOISE CONTROL TREATMENTS

摘要

The noise of the industrial combustion turbine can be controlled at several stages and should be viewed as asystem rather than as a noise source with an inlet and exhaust silencer. At the combustion turbine design phase,the noise can be controlled through the selection of appropriate blade/vane combinations and spacings of thecompressor and turbine stages, a stable combustion design, and well distributed low velocity exhaust flow. Theinlet and exhaust silencers and the selection of appropriate locations within the system for the placement of theacoustic treatment can then be integrated into the combustion turbine design phase to optimize performance whileminimizing cost. In some cases, the type of silencing seleeted can actually modifi the apparent sound power levelemitted by the inlet and exhaust of the combustion turbine. A poorly designed exhaust stack can actually generateadditional noise due to flow impacting the walls or by causing poor flow distribution within the silencer passages.While the apparent sound power level of the combustion turbine can be treated in a conventional way byincreasing silencer length and using high surface weight wall designs, it may be more effective to find the cause ofthe noise and reevaluate the design of the system.