MSFI TECHNOLOGY AT SAFRAN AIRCRAFT

Transcription

1 MSFI TECHNOLOGY AT SAFRAN AIRCRAFT ENGINES S. BOURGOIS 08/03/2017 Ce document et les informations qu il contient sont la propriété de Safran. Ils ne doivent pas être copiés ni communiqués à un tiers sans l autorisation préalable et écrite de Safran.

2 Summary MSFI (Multiple Staged Fuel Injection) is Safran Aircraft Engines technology aiming at lean combustion in future engines. It is developed in particular in the frame of LEMCOTEC. Reminders on the objectives of Safran Aircraft Engines within the LEMCOTEC project Objectives for Safran Aircraft Engines Target application for the assessment of performance Overview of the test campaigns planned in the LEMCOTEC project Experimental results on the MSFI system (in collaboration with ONERA) Choice of the best MSFI configuration Pollutant emissions and PLIF measurements on an MSFI injection system at idle, cruise and climb conditions Some results from LES simulations (in collaboration with CERFACS and CORIA) Comparison of experimental and numerical results OGV Combustor interactions Perspectives Full annular (FANN) Combustor test campaigns at DGA EP (2017) Technical status 2

3 Overview of Multipoint Injection System development at Safran Aircraft Engines 3

4 LEMCOTEC: objectives for Safran Aircraft Engines LEMCOTEC: Low Emissions Core-Engine Technologies MSFI Combustor Objectives : Conception of a full annular combustor (TRL5) with multipoint technology «Low NOx / Low particles» Tests in representative operating conditions Tools: Assessment of LEMCOTEC combustor performances by means of RANS / LES computations and single sector / four sectors and full annular tests Simulations intended to estimate combustor performances: temperature profiles, pollutant emissions, stability, ignition Nearly completed tests at ONERA on single/multi-sectors combustors FANN combustor tests in April 2017 MSFI Injector 4

5 Overview of the test campaigns planned in the LEMCOTEC project One sector rig test (ONERA M1) for the choice of the injector geometry to be integrated on the FANN combustor (criteria: CO at low conditions / NOx at high conditions) One sector rig test (ONERA M1) for pollutant emissions characterization (NOx, CO, UHC, SN) of the down-sized injector chosen for the LEMCOTEC FANN combustor Focus On-going Four sectors rig test (ONERA M1) at low pressure and sub atmospheric conditions: April 2017 Stability and ignition capabilities, optimisation of fuel staging regarding combined requirement for operability and pollutant emissions reduction at part power conditions FANN Combustor High Pressure test campaign (DGA EP K8 bench): Pollutant emissions, aerodynamic behaviour and air flow split, thermal behaviour on the combustor liners heat shields, temperature profiles at the combustor outlet, thermo-acoustic behaviour April 2017 FANN Combustor Altitude Relight test campaign (DGA EP A06 bench): Sept Stability and ignition domains of the FANN combustor for several altitudes relight conditions in terms of air pressure and temperature at the combustor inlet, the effect of fuel temperature and composition 5

6 Choice of the best MSFI configuration EICO=f(FAR) at idle Three versions of the MSFI system (B2.1, D8 and E5) have been tested on a one TLC sector at ONERA M1 test bench and compared to the previous optimal configuration (TOSCA): combustion performances and lean blow out limits, effect of fuel staging The configuration D8 has been selected for its performances in terms of CO at low conditions and NOx at high conditions. TLC Sector with 4 optical accesses TOSCA D8 LEMCOTEC PLIF-OH and PLIF Kerosene have been simultaneously used to correlate the flame structure and fuel placement with the combustion performances on TOSCA and D8 configurations 6 PLIF-Fuel (colour) and PLIF-OH (white)

7 Characterization of the D8 MSFI Injection system: results at idle Comparison of instantaneous images of PLIF-fuel and PLIF-OH between TLC, TOSCA and D8 at idle D8 TOSCA TLC Superposition Fuel / OH EICO=f(FAR) EIUHC=f(FAR) 7

8 Characterization of the D8 MSFI Injection System: results at cruise Comparison of instantaneous images of PLIF-fuel and PLIF-OH between TOSCA and D8 at cruise Superposition Fuel / OH D8 TOSCA EINOx=f(FAR) 16,6% 14,9% 9,8% 15,1% 10,0% 15,1% 13,0% 15,1% 9,9% 16,0% 15,0% 10,0% 10,8% 15,1% 19,4% 0,015 0,020 0,025 0,030 0,035 11,9% % indicates fuel pilot / main ratio Config D8 TOSCA optimisé TLC P = 16,5b The optimisation of the MSFI system is very sensitive, a small modification on the pilot bowl leads to important differences in running Overall achieved results are promising with EINOx levels lower than 5g/kg at cruise 8

9 Characterization of the D8 MSFI Injection System: results at climb condition NOx levels at climb condition on the MSFI D8 geometry are reduced d by 50-60% in comparison to levels measured on the TOSCA injection system EINOx=f(FAR) The fuel split between the pilot and the main injections has limited influence 9

10 LES simulation on the MSFI D8 configuration: Comparison of experimental and numerical results Operating point: cruise condition Similar flame topology (M-shape between the pilot and the main injection zone) and kerosene distribution at the exit of the MSFI system. system NOx levels evaluated by means of CFD on the D8 configuration are very close to the values measured experimentally. OH Experiments PLIF-Fuel (colour) and PLIF-OH (white) LES simulation (AVBP) 10 Ykero and Zeldovitch

11 LES simulation on the MSFI FANN combustor: OGV Combustor interactions Aim: study of the interactions between the disturbances coming from the detached flow of the OGV and the aerodynamic flow inside the combustor Computation made on the MSFI combustor. Mesh consists of about 110 million finite elements. Reactive LES simulation using the YALES2 code developed by CORIA. Analysis of the topology of the flow inside the combustor and the flame structures Visualization of the coherent structures downstream the OGV and inside the combustor 11

12 FANN Combustor test campaigns at DGA EP (2017) Two test phases of the full annular (FANN) combustor will be run in DGA EP test plan area in Saclay: High pressure tests (K8 test rig) Sub atmospheric pressure tests (A06 test rig) Objectives of the K8 test: Evaluation of the pressure losses and the flow distribution around the combustor Detection of the combustion instabilities Gas and smoke emission measurements Temperature profiles and wall temperatures measurements HP tests AR tests Test rig K8 A06 Pressure Max 22bar Min 0.3bar Temperature Max 873K Min 245K Mass flow Max 20kg/s Max 2kg/s Planned test phase April 2017 September 2017 Objectives of the A06 test: Relight capability measurements, sub-atmospheric relight envelope Plug immersion optimisation The two campaigns will make possible claiming a TRL5 for the MSFI technology Assembly of the K8 test bench in progress 12

13 LEMCOTEC: Target application for the assessment of performance The Mid-size Open Rotor engine has an OPR of around 45:1 and is designed for a short/medium range mission. The propulsor architecture consists of a contra-rotating geared drive pusher configuration. The engine is equipped with a MSFI (Multi-Stage Fuel Injection) lean combustion system with innovative fuel controls that will enable NOx reduction and allow for improved combustor-turbine interaction. Reduction Targets Datum MOR CO 2 vs. Year % NO x 70% CO 50% vs. CAEP/2 UHC 50% Smoke 75% Results of preliminary emissions and performance assessment are based on a LTO cycle for the Mid-size Open Rotor. 13 Preliminary Reduction Achieved (December 2016) Datum MOR CO 2 Year % Injection System MSFI 70.3% NO x (65.6% vs CAEP/6) vs. CO n/a CAEP/2 UHC n/a Smoke n/a

14 Conclusions and perspectives Available experimental data on the emissions performances of the MSFI injection system are promising and need to be validated with the forthcoming LEMCOTEC FANN combustor tests at DGA EP. NOx emissions: 65% margin vs CAEP/6 demonstrated with the MSFI technology, with forthcoming TRL5 maturity. LES simulations show good agreement with optical characterization (PLIF) of the flame structure and is an efficient support for the design. Assessment of the NOx emission index in cruise condition has to be made and consolidated with the LEMCOTEC FANN combustor tests. 14