When gas turbine is used in coal co-production system, its combustor needs to burn syngas produced by coal gasification. The syngas’ main combustible compositions are CO and H2 , and it has a nominal lower heating value of 10920kJ/ncm. In this paper, three modification schemes of a heavy-duty gas turbine combustor burning syngas are proposed. Flow fields, temperature profile and chemical reaction characteristics are compared using three-dimensional CFD numerical simulation and two of them have been chosen for medium-pressure, full-scale tests at the Gas Turbine Combustor Laboratory of the Institute of Engineering Thermophysics, Chinese Academy of Sciences. Laboratory tests show good result in exhaust emissions, combustor efficiency, exhaust temperature profile, and metal temperature distribution of liner and transaction pieces, which indicate that the retrofitting schemes satisfied the design specification. In addition, the dynamic characteristics of the combustors are researched applying FFT and wavelet analyses.Copyright © 2005 by ASME