CFD insight of the flow dynamics in a novel swirler for gas turbine combustors

We describe the flow dynamics inside a novel swirler conceptualized for gas turbine combustors. The supreme advantage in this swirler is the ability to vary the swirl number for the same value of Reynolds number. The significance of such advantage against contemporary configurations, which have constant swirl number, is quite evident at low turbine operating loads. The novel geometry and flow pattern are described in details in the present work. The results of four numerical simulations are presented and discussed to study the central recirculation zone, turbulence intensity, and pressure drop at different swirl numbers. The new concept is deemed to enhance the combustion efficiency because of its ability to adjust the swirl number according to the turbine operating load. The current study reports preliminary results which verify the concept behind the proposed swirler. However, intensive numerical and experimental studies are necessary to be carried out in order to characterize the flow dynamics produced by the novel swirler and its impact on the combustion process.

[1]  T. O’Doherty,et al.  Vortex breakdown: a review , 2001 .

[3]  S. Patankar.  Numerical Heat Transfer and Fluid Flow , 2018, Lecture Notes in Mechanical Engineering.

[4]  Ephraim Gutmark,et al.  Experimental and Numerical Studies of the Velocity Field of a Triple Annular Swirler , 2002 .

[5]  Ephraim Gutmark,et al.  Geometry Effects on the Flow Field and the Spectral Characteristics of a Triple Annular Swirler , 2003 .

[6]  Yongqiang Fu,et al.  Characteristics of the Swirling Flow Generated by an Axial Swirler , 2005 .

[7]  Mohammad Nazri Mohd. Jaafar,et al.  NUMERICAL INVESTIGATION OF THE FLOW INSIDE PRIMARY ZONE OF TUBULAR COMBUSTOR MODEL , 2008 .

[8]  Mohammad Nazri Mohd. Jaafar,et al.  Investigation of Radial Swirler Effect on Flow Pattern inside a Gas Turbine Combustor , 2009 .

[9]  B. Launder,et al.  Lectures in mathematical models of turbulence , 1972 .

[10]  C. Lee,et al.  An experimental investigation of the effects of turbulence generators attached to an axial swirler nozzle on mixing and combustion , 2002 .

[11]  Jiyuan Tu,et al.  Computational Fluid Dynamics: A Practical Approach , 2007 .

[12]  Ji Hong-hu.  Experimental study of effects of geometric parameters on combustion performance of dual-stage swirler combustor , 2007 .

[13]  Pramod K. Subbareddy,et al.  43rd AIAA Aerospace Sciences Meeting and Exhibit - Meeting Papers , 2005 .

[14]  Henry Cohen,et al.  Gas turbine theory , 1973 .

[15]  Ahmed Mostafa Elkady,et al.  Fuel and Equivalence Ratio Effects on Spray Combustion of a Counter-rotating Swirler , 2005 .

[16]  Richard J Goldstein,et al.  Film cooling effect of rotor-stator purge flow on endwall heat/mass transfer , 2010 .

[17]  János M. Beér,et al.  Combustion in swirling flows: A review , 1974 .

[18]  B. Launder,et al.  The numerical computation of turbulent flows , 1990 .

[19]  Philip J. Smith,et al.  Modeling of swirl in turbulent flow systems , 1986 .

[20]  David G. Lilley.  Annular Vane Swirler Performance , 1999 .

[21]  Hukam Mongia,et al.  Characteristics of the Swirling Flow Generated by a Counter-Rotating Swirler , 2007 .

[22]  M. Jaafar,et al.  PREDICTION OF THE FLOW INSIDE A MICRO GAS TURBINE COMBUSTOR , 2008 .