Experimental study on laminar flow over two confined isothermal cylinders in tandem during mixed convection
Por:
Salcedo, E., Treviño, C., Palacios-Morales, C., Zenit, R., Martínez-Suástegui, L.
Publicada:
1 may 2017
Resumen:
An experimental investigation of laminar aiding and opposing mixed
convection is carried out using particle image velocimetry (PIV) to
assess the thermal effects on the wake of two isothermal cylinders of
equal diameter in tandem array placed horizontally and confined inside a
vertical closed-loop downward rectangular water channel. The buoyancy
effect on the flow distributions are revealed for flow conditions with
Reynolds number based on cylinder diameter of Re = 100 and 200, blockage
ratio of BR = D/H = 03, aspect ratio of AR = W/D = 5, pitch-to-diameter
ratio of sigma = L/D = 3, and values of the buoyancy parameter
(Richardson number) in the range -1 <= Ri <= 3. In this work, the
interference effects on the complex flow features are presented in the
form of mean and instantaneous contours of velocity and vorticity. In
addition, separation angles, wake structure, recirculation bubble
lengths, time traces of velocity fluctuation, Strouhal number and vortex
shedding modes of the two-cylinder system are obtained as a function of
the Richardson number. In this arrangement, the results indicate that
the effects of the Reynolds number are very pronounced, and that the
vortex shedding patterns exhibit a strong dependence on Ri. We also show
the modulation effect of the channel walls on the three-dimensional flow
under varying thermal buoyancy, and the results reported herein
demonstrate how the flow structure, wake behavior and vortex shedding
pattern are entirely different from that behind a single circular
cylinder under wall confinement and thermal effects. (C) 2017 Elsevier
Masson SAS. All rights reserved.
Filiaciones:
Salcedo, E.:
Departamento de Termofluidos, Facultad de Ingeniería, Universidad Nacional Autónoma de México, Av. Universidad 3000, Ciudad de México, México, Mexico
Treviño, C.:
UMDI, Facultad de Ciencias, Universidad Nacional Autónoma de México, Sisal, Yucatán, Mexico
Palacios-Morales, C.:
Facultad de Ingeniería, Universidad Nacional Autónoma de México, Ciudad de México, México, Mexico
Zenit, R.:
Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Ciudad de México, México, Mexico
Martínez-Suástegui, L.:
ESIME Azcapotzalco, Instituto Politécnico Nacional, Avenida de las Granjas No. 682, Colonia Santa Catarina, Delegación Azcapotzalco, Ciudad de México, México, Mexico
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