New On Line Washing Technique for Prevention of Performance Deterioration due to Fouling on Steam Turbine Blades : 1st Report, Fouling Phenomena, Conventional Washing Technique and Disadvantages

摘要

Mechanical-drive steam turbines have the heavy deposition of fouling materials on blade and nozzle path surfaces due to contaminated materials such as silica and sodium in steam. As a result, turbine performance tends to be deteriorated gradually. This first paper introduces this fouling phenomena and actual conventional washing procedure in order to prevent the fouling problem and its practical disadvantage by showing thermodynamics analysis. In the second report, the new online washing technology by water injection nozzles is introduced and the most important design factors of this washing system are discussed by showing the results of detail analysis and online washing test results.