Experimental study of flow dynamics and fuel spray characteristics in Lean Premixed Prevaporized Combustor

• A LPP combustor with staged lean combustion technology is proposed.
• Flow dynamics in the LPP combustor dome are revealed by using the PIV.
• Image-processing procedure about droplet diameter and distributions is compiled.
• The fuel spay characteristics in LPP combustor are investigated.

Further improving the emission performance of a Lean Premixed Prevaporized (LPP) combustor is a hot topic for gas turbine research. An in-depth understanding of the combustion characteristics is therefore highly desirable. In this paper, the flow fields and fuel spay characteristics in a LPP combustor are experimentally studied by using Particle Image Velocimetry (PIV). The effects of the fuel allocation and pilot atomizer position on fuel spray characteristics are investigated. Experimental results show that: (1) A Primary Recirculation Zone (PRZ), Corner Recirculation Zone (CRZ) and Lip Recirculation Zone (LRZ) are presented in the flow field in a LPP combustor; (2) The width of the primary recirculation zone initially increases along axial direction from the combustor inlet, and starts to decrease after certain distance; (3) When only the pilot atomizer is operated, the fuel spray characteristics is worsened with the increase of fuel flow rate. Locating the pilot atomizer at the throat results is a better fuel spray distribution than locating it at the outlet of the pilot swirler. The present results are useful for future development of the LPP combustor.