ARTICLE | doi:10.20944/preprints201805.0077.v1
Subject: Engineering, Automotive Engineering Keywords: turbulence; CFD; incompressible flow; velocity profiles
Online: 3 May 2018 (12:44:14 CEST)
In this paper, we studied and analyzed the behavior of velocity profiles and the distribution of pressures in a pipe connected to an accessory. In this case, it was a 90º elbow fitting in which water flows as an incompressible flow. This study was developed numerically through the fluent program of ANSYS. It is of practical interest in engineering because it is based on results regarding the internal structure of a model of incompressible flows. In the same way, it provides a basis for the proper design and implementation of velocity profiles within an elbow.In the agricultural industry, suitable systems can be implemented for crop irrigation in this way with the results obtained to improve the design in the fluid distribution system.We used a feasible κ-ε turbulence model because this model causes less turbulence than the standard κ-ε model. A mesh independence study was developed, in which it was observed that combining different densities of meshes for the same geometry causes some variables, so a fine meshing was used to carry out the study so that the results are as close to reality as possible.
ARTICLE | doi:10.20944/preprints202207.0166.v1
Subject: Mathematics & Computer Science, Analysis Keywords: incompressible micropolar ﬂows; vorticity and micro-rotation; dissipative systems; monotonicity method; upper and lower estimates
Online: 12 July 2022 (04:03:22 CEST)
In this work the close relation between vorticity and micro-rotation in micropolar flows in Rn (n = 2 or 3) is identified and used to explain the faster decay by t^(-1/2) of the angular velocity of the micro-rotation of fluid particles, as well as establishing its optimality. For this purpose important upper and lower bounds for Leray solutions in homogeneous Sobolev spaces are derived, using the monotonicity approach recently introduced by the authors for dissipative systems in general. Several related results of interest are also given along the discussion.