Combustion System Development and Testing for MAN’s New Industrial Gas Turbines MGT 6100 and MGT 6200

Abstract

This paper describes the development and test results of the low emission combustion system for the new industrial gas turbines in the 6–7 MW class from MAN Diesel & Turbo. The design of a robust combustion system and the achievement of very low emission targets were the most important design goals of the combustor development. During the design phase, the analysis of the combustor (i.e. burner design, air distribution, liner cooling design) was supported with different CFD tools. This advanced Dry Low Emission can combustion system (ACC) consists of 6 cans mounted externally on the gas turbine. The behavior and performance of a single can sector was tested over a wide load range and with different boundary conditions; first on an atmospheric test rig and later on a high pressure test rig with extensive instrumentation to ensure an efficient test campaign and accurate data. The atmospheric tests showed a very good performance for all combustor parts and promising results. The high pressure tests demonstrated very stable behavior at all operation modes and very low emissions to satisfy stringent environmental requirements. The whole operation concept of the combustion system was tested first on the single-can high pressure test bed and later on twin and single shaft gas turbines at MAN’s gas turbine test facility. During the engine tests, the can combustors demonstrated the expected combustion performance under real operation conditions. All emissions and performance targets were fully achieved. On the single shaft engine, the combustors were running with single digit ppm NOx levels between 50% and 100% load. The validation phase and further optimization of the gas turbines and the engine components are ongoing. The highlights of the development process and results of the combustor and engine tests will be presented and discussed within this paper.

Enhancement of Impingement Heat Transfer With the Crossflow Normal to Ribs and Pins Between Each Row of Holes

“…Gas turbine (GT) wall cooling technologies often use impingement heat transfer and require that the design is optimized for effective wall cooling. Although impingement cooling is often combined with effusion cooling to enhance the internal wall cooling [1] for combustor wall cooling applications, there are potential advantages of using impingement only backside cooling in low NO x combustors [2]. The main advantage of impingement only backside cooling is that with no film cooling air all the primary zone combustion air can pass through the low NO x combustor after it has regeneratively cooled the combustor wall.…”

“…A low G and high pressure loss impingement design gives a high X/D ratio and 12/1 is typical [4]. In contrast the backside impingement only cooling requires a very high coolant G set by the total combustor primary zone mass flow requirements [2]. Also, it must have a low pressure loss or there is no pressure loss left for the low NO x flame stabilizer and this requires a low impingement X/D and 4.7 was used in the present work.…”