51. The Acoustic Scintillation Flow Meter – A Breakthrough in Short Intake Turbine Index Testing Lemon David D., Billenness David, Lampa Josef (Proceedings, Hydro 2003, Vol. I, Croatia, pp. 87–92). Abstract After many years of relatively little technological progress in turbine discharge measurements in short intakes of low-head plants, the Acoustic Scintillation Flow Meter (ASFM) now offers a significant improvement. In recent years, several North American plant owners have discovered the ASFM's unprecedented ease of use and labour and cost effectiveness in producing highly repeatable discharge measurement results under very demanding hydraulic conditions prevalent in these short, rapidly converging intakes. Personnel from one utility recently estimated that in comparison with the current meter method, the ASFM saves a minimum of 10 to 20% of the cost of instrumentation procurement, installation and field testing and, often more importantly, at least two days of generation outage. The paper briefly describes the ASFM technology and its application in turbine index testing during the last 5 years. The results from repeat measurements carried out at a number of North American hydroelectric projects are given in detail, demonstrating the ASFM's capability to produce repeatable results with an acceptable – on average, about ± 0.5% - random uncertainty in these hydraulically difficult intakes. It is noted that acceptable precision was obtained even when these intakes were equipped with fish diversion devices. The cost-effectiveness of using the ASFM is further illustrated by examples of the efficiency gains obtained from improved operation of poorly indexed or adjusted units. Top Keywords Turbine, Low-head, ASFM, Discharge, Index, Efficiency. Top |