Entropy generation analysis as design criteria in dam-break flows for non-Newtonian fluids
Department of Mechanical Engineering, Hakim Sabzevari University, Sabzevar, Iran
* e-mail: email@example.com
Accepted: 16 September 2018
Published online: 6 November 2018
In the present study, a novel equation is presented for entropy generation (EG) in dam-break flows of Herschel-Bulkley fluids. The Herschel-Bulkley model is an idealized model of viscoplastic behavior. The dam-break phenomena can cause floods and widespread destruction in the path of the flow. Therefore, finding a measure for destruction analysis in downstream of the dam is important. Therefore, the EG is introduced as a criterion of destruction analysis in non-Newtonian dam-break flows. The Open-FOAM software is employed and simulations are done by the modified VOF method. Results are compared with experimental data, and a good agreement is achieved. The EG analysis of the Herschel-Bulkley fluid is presented for the first time. It is computed for different initial height (H0), and the results show that the enhancement of H0 causes the increment of EG. And, also, for an increment of EG, different shapes of bump are simulated and the geometry and bump distance from the dam are optimized. As a result, the triangle bump with , , and has the best performance in increasing the EG. Focusing on the destruction of the available work in the dam-break flows of Herschel-Bulkley fluids is important and useful for designing dams and structures in the downstream of dams.
© Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature, 2018