Amnart Boonloi^a, Withada Jedsadaratanachai^b,*

Frontiers in Heat and Mass Transfer, Vol.12, pp. 1-9, 2019, DOI:10.5098/hmt.12.1

Abstract Numerical examinations on flow and heat transfer behaviors in a square channel heat exchanger equipped with various configurations of V-wavy plate are performed. The pitch-to-channel height ratios, wavy height-to-channel height ratios and flow directions of the test section are investigated for the Reynolds number in the range of 100 – 1000 (laminar flow regime). The finite volume method is selected for the present investigation. The results are reported in terms of flow and heat transfer mechanisms in the channel. The thermal performance assessments of the square channel fitted with the V-wavy plate are also concluded. As the numerical results, the… More >

Zaiguo Fu^{1, *}, Huanhuan Gao¹, Zhuoxiong Zeng¹, Jiang Liu¹

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.3, pp. 805-830, 2020, DOI:10.32604/cmes.2020.08825

Abstract In order to comprehensively evaluate the flow and heat transfer performance of a large-size annular combustion chamber of a heavy-duty gas turbine, we carried out numerical computation and analyses on the velocity, temperature and pressure fields in the chamber with double swirlers. The mathematical model of the coupling combustion, gas flow, and heat transfer process was established. The influences of the inlet swirling strength, fuel-air ratio and temperature of the premixed gas on the multi-field characteristics and synergy were investigated on the basis of field synergy theory. The results showed that the central recirculation zone induced by the inlet swirling… More >

Hui-Fen Guo^1,2, Bin-Gang Xu^1,3, Sheng-Yan Li¹, Chong-Wen Yu²

CMES-Computer Modeling in Engineering & Sciences, Vol.80, No.2, pp. 87-112, 2011, DOI:10.3970/cmes.2011.080.087

Abstract Three-dimensional transient simulation is presented for swirling recirculating flow in a nozzle with a slotted-tube (different grooves) and the effect of the groove number is also investigated. The numerical results on the streamline angles are validated by experimental visualization using the surface oil flow technology. In the downstream center of the injectors, the vortex breakdown experiences a transition from bubble- to spiral- breakdown as time is increased. For all cases under study, as the sizes of two recirculation zones near the injector upstream wall and the step retain almost constant, the spiral breakdown shows a periodic development. The more the… More >

Hui-Fen Guo^1,2, Bin-Gang Xu^1,3

CMES-Computer Modeling in Engineering & Sciences, Vol.61, No.3, pp. 201-222, 2010, DOI:10.3970/cmes.2010.061.201

Abstract A numerical method is developed for modeling the dynamics of a flexible fiber immersed in a compressible swirling flow. The modeling approach is based on combining an Eulerian finite volume formulation for the fluid flow and a Lagrangian small-deformation formulation for the dynamics of the fiber. The fiber is modeled as a chain of beads connected through mass-less rods. The bending and twisting deformation of the fiber are represented by the displacements of the successive beads. A computational strategy is proposed for the computation of the fluid parameters at the center of discrete fiber sections. To deal with the fiber-wall… More >

I. Karagoz, F.Kaya

CMES-Computer Modeling in Engineering & Sciences, Vol.43, No.2, pp. 111-130, 2009, DOI:10.3970/cmes.2009.043.111

Abstract The aim of this work is to investigate the suitability of various turbulence models and their options for highly complex swirling flows in tangential inlet cyclones. Three-dimensional, steady governing equations for the incompressible, turbulent flow inside the cyclone are solved numerically. The prediction performance of three popular turbulence models and various options available for these models was evaluated by comparing the computed velocity profiles and pressure drop with the experimental data given in the literature. Results obtained from the numerical tests have demonstrated that the swirl factor for the RNG k-emodel has considerably influence on the prediction performance of the… More >

Brahim Mahfoud¹, Rachid Bessaih^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.8, No.1, pp. 1-26, 2012, DOI:10.3970/fdmp.2011.008.001

Abstract Oscillatory swirling flows in a cylindrical enclosure, having aspect ratio (height/radius) γ=2, filled with a liquid metal, and submitted to a destabilizing vertical temperature gradient (system heated from below) is investigated by means of direct numerical solution of the governing (continuity, radial and axial momentum,swirlandenergy)equations. The bottom and top disks are assumed to rotate at equal (co-rotating) and opposite (counter-rotating) angular velocities. The critical Reynoldsnumber,Re_cr and the critical frequency of oscillations, F_cr arecalculated as a function of the Richardson number, Ri, ranging between 0 and 4. Stability diagrams are presented, reflecting the results of the numerical investigation, which put in… More >