Three Methods for Estimating the Entropy Parameter M Based on a Decreasing Number of Velocity Measurements in a River Cross-Section

Entropy

Giulia Farina¹  Stefano Alvisi¹  Marco Franchini¹ 

[1] Engineering Department, University of Ferrara, Via Saragat 1, 44122 Ferrara, Italy; E-Mails:

关键词: entropy;    streamflow measurement;    velocity profile;   

DOI  :  10.3390/e16052512

来源: mdpi

【 摘 要 】

The theoretical development and practical application of three new methods for estimating the entropy parameter M used within the framework of the entropy method proposed by Chiu in the 1980s as a valid alternative to the velocity-area method for measuring the discharge in a river is here illustrated. The first method is based on reproducing the cumulative velocity distribution function associated with a flood event and requires measurements regarding the entire cross-section, whereas, in the second and third method, the estimate of M is based on reproducing the cross-sectional mean velocity Ū by following two different procedures. Both of them rely on the entropy parameter M alone and look for that value of M that brings two different estimates of Ū, obtained by using two different M-dependent-approaches, as close as possible. From an operational viewpoint, the acquisition of velocity data becomes increasingly simplified going from the first to the third approach, which uses only one surface velocity measurement. The procedures proposed are applied in a case study based on the Ponte Nuovo hydrometric station on the Tiber River in central Italy.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland