Experimental study of flow characteristics of enhanced biogas lean premixed nozzle of micro gas turbine by PIV

Abstract Distributed energy supply (DES) systems based on biogas micro gas turbines can effectively improve the energy consumption level in rural areas, and China paid more attention to the biogas DES system. In order to improve the combustion performance and fuel adaptability of biogas lean premixed nozzles, in this work, two enhanced lean premixed nozzles (EPN1 and EPN2) redesigned from the original premixed nozzle (OPN) of a 60 kW class micro gas turbine were tested. A single nozzle test bench was designed and built to investigate the main characteristics of flow field in the combustor and nozzles using two-dimensional planar Particle Image Velocimetry (PIV). Proper orthogonal decomposition (POD) was used to capture the coherent structures at the outlet of nozzles. The results show the maximum value of TKE for EPN1 is approximately 50.9% lower than that of OPN. The absolute value of vorticity in EPN1 increase from 49 s −1 to 255 s −1 along the mixing tube, and strong swirl enhances the mixing of fuel and air. The flow energy in EPN1 and EPN2 are more concentrated in 1–10 mode. There are less fluctuations and instabilities of the flow field at the outlet of EPN1. Therefore, the enhanced lean premixed nozzle (EPN1) has better flow characteristics.

[1]  Abdelkrim Boukhalfa,et al.  Experimental study of biogas combustion using a gas turbine configuration , 2007 .

[2]  P. A. Pilavachi.  Mini- and micro-gas turbines for combined heat and power , 2002 .

[3]  David J. Lucia,et al.  Reduced order modeling of a two-dimensional flow with moving shocks , 2003 .

[4]  A. Masri,et al.  Effect of the mixing fields on the stability and structure of turbulent partially premixed flames in a concentric flow conical nozzle burner , 2017 .

[5]  Melanie Voges,et al.  Combined PIV and DGV applied to a pressurized gas turbine combustion facility , 2006 .

[6]  Muruhan Rathinam,et al.  A New Look at Proper Orthogonal Decomposition , 2003, SIAM J. Numer. Anal..

[7]  M. Stöhr,et al.  Experimental analysis of thermo-acoustic instabilities in a generic gas turbine combustor by phase-correlated PIV, chemiluminescence, and laser Raman scattering measurements , 2015 .

[8]  M. Effenberger,et al.  Agricultural biogas production in Germany - from practice to microbiology basics , 2014 .

[9]  D. Littlejohn,et al.  Laboratory Studies of the Flow Field Characteristics of Low-Swirl Injectors for Adaptation to Fuel-Flexible Turbines , 2008 .

[11]  L. Sirovich.  Turbulence and the dynamics of coherent structures. I. Coherent structures , 1987 .

[12]  K. Maruta,et al.  Microscale combustion: Technology development and fundamental research , 2011 .

[13]  Ajay K. Agrawal,et al.  Time-resolved PIV of lean premixed combustion without and with porous inert media for acoustic control , 2015 .

[14]  S. Ekkad,et al.  Isothermal coherent structures and turbulent flow produced by a gas turbine combustor lean pre-mixed swirl fuel nozzle , 2017 .

[15]  P. Weiland.  Biogas production: current state and perspectives , 2009, Applied Microbiology and Biotechnology.

[16]  C. Mordaunt,et al.  Design and Preliminary Results of an Atmospheric-Pressure Model Gas Turbine Combustor Utilizing Varying CO2 Doping Concentration in CH4 to Emulate Biogas Combustion , 2014 .

[17]  J. Driscoll,et al.  Combustion instability of a lean premixed prevaporized gas turbine combustor studied using phase-averaged PIV , 2014 .

[18]  T. Lieuwen.  Unsteady Combustor Physics , 2012 .

[19]  S. Zang,et al.  Experimental investigations and large-eddy simulation of low-swirl combustion in a lean premixed multi-nozzle combustor , 2015 .

[20]  Aiguo Liu,et al.  Effects of Lower Heat Value Fuel on the Operations of Micro-Gas Turbine , 2009 .

[21]  Yiwu Weng,et al.  Thermodynamic characteristics of a low concentration methane catalytic combustion gas turbine , 2010 .

[22]  T. Schmidt,et al.  Explaining the diffusion of biogas in India: a new functional approach considering national borders and technology transfer , 2014 .

[23]  David A. Ham,et al.  POD reduced-order unstructured mesh modeling applied to 2D and 3D fluid flow , 2013, Comput. Math. Appl..

[24]  Christian Breitsamter,et al.  Efficient unsteady aerodynamic loads prediction based on nonlinear system identification and proper orthogonal decomposition , 2016 .

[25]  K. Hur,et al.  An analysis of CH4/N2 rich biogas production, fuel treatment process and microturbine application , 2011 .

[26]  Christopher S. Galik,et al.  Biogas in the United States: estimating future production and learning from international experiences , 2017, Mitigation and Adaptation Strategies for Global Change.