Development of RANS turbulence models for complex geometries in turbulent viscoelastic fluid flows

• Grant number: 13/01521-4
• Support Opportunities: Regular Research Grants
• Start date: May 01, 2013
• End date: April 30, 2015
• Field of knowledge: Engineering - Mechanical Engineering - Transport Phenomena
• Principal Investigator: Pedro Miguel Rebelo Resende
• Grantee: Pedro Miguel Rebelo Resende
• Host Institution: Universidade Estadual Paulista (UNESP). Campus Experimental de Sorocaba. Sorocaba , SP, Brazil
• Associated researchers: Fernando Manuel Coutinho Tavares de Pinho ; Paulo Jorge dos Santos Pimentel de Oliveira

Abstract

The reduction of drag in turbulent flow of polymeric solutions was discovered by Toms' in 1949. Subsequently heat transfer was also observed to decrease substantially, allowing significant cost reductions in thermal energy transport in flows. The viscoelastic fluids are present in many industrial processes and under turbulent conditions. And the advantage of the drag reduction phenomenon by using this type of fluids can be observed in fluid transport at long distances and in heat and refrigeration systems, such as in district heating systems. Therefore, it is necessary to develop adequate turbulence models that can be used to solve engineering problems. Actually there are models that can accuracy predict relevant quantities, like for example Resende et al. [1-5], but they only were tested in simple geometries like channel and pipe turbulent flows. The main objective of the present work is precisely to expand this viscoelastic models to complex geometries, such as recirculation turbulent flows with viscoelastic fluids with different degree of drag reduction. This part are divide in three phases: (1) development and implementation of viscoelastic turbulent models into an in-house 3D code. The models are k-[ and k-É type, which use the FENE-P model, based in the theory kinetic energy, to describe the rheology of the fluid; (2) numeric simulation of viscoelastic fluids in turbulent flows with recirculation; (3) analysis of the elastic effect in the dynamic behaviour of the turbulent flows with viscoelastic fluids for the different drag reductions degrees.Although the numeric simulations development in the turbulent flows dynamics with viscoelastic fluids, they have not been tested to predict the viscoelastic dynamics in complex geometries, necessary to heating systems design. For this reason, in the second part of this project it will be analyzed and verified the performance of the viscoelastic turbulent models, comparing with experimental data. The governing equations, necessary to predict the velocity field, are made through the Reynolds-averaged Navier-Stokes (RANS) viscoelastic turbulence models developed previously by Resende et al. [1-5]. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

RESENDE, P. R.; AFONSO, A. M.; CRUZ, D. O.. An improved k-epsilon turbulence model for FENE-P fluids capable to reach high drag reduction regime. INTERNATIONAL JOURNAL OF HEAT AND FLUID FLOW, v. 73, p. 30-41, OCT 2018. (13/01521-4)