IEC TS 62882:2020

Hydraulic machines – Francis turbine pressure fluctuation transposition


Status:
Current
Type:
Standard
Language:
English
Price from:
€ 314.84

Scope

IEC/TS 62882:2020(E) which is a Technical Specification, provides pressure fluctuation transposition methods for Francis turbines and pump-turbines operating as turbines, including: – description of pressure fluctuations, the phenomena causing them and the related problems; – characterization of the phenomena covered by this document, including but not limited to inter-blade vortices, draft tube vortices rope and rotor-stator interaction; – demonstration that both operating conditions and Thoma numbers (cavitation conditions) are primary parameters influencing pressure fluctuations; – recommendation of ways to measure and analyse pressure fluctuations; – identification of potential resonances in test rigs and prototypes; – identification of methods, to transpose the measurement results from model to prototype or provide ways to predict pressure fluctuations in prototypes based on statistics or experience; – recommendation of a data acquisition system, including the type and mounting position of model and prototype transducers and to define the similitude condition between model and prototype; – presentation of pressure fluctuation measurements comparing the model turbine and the corresponding prototype; – discussion of parameters used for the transposition from model to prototype, for example, the peak to peak value at 97 % confidence interval, the RMS value or the standard deviation in the time domain and the relation of main frequency and the rotational frequency in the frequency domain obtained by FFT; – discussion of the uncertainty of the pressure fluctuation transposition from model to prototype; – discussion of factors which influence the transposition, including those which cannot be simulated on the model test rig such as waterway system and mechanical system; – establishment of the transposition methods for different types of pressure fluctuations; – suggestion of possible me ...

Number of pages: 0

Published: 2020-09-18

International relationships :

ICS: 27.140 - Hydraulic energy engineering

Item number: M336456


Committees

Committee

  • IEC/TC 4