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1 Scientific coordination: Dr. Arvind G. Rao AHEAD : Advanced Hybrid Engines for Aircraft Development 1- 284636) Level 1: Start 1/10/2011, duration 3 years 2 Main Challenges in Civil Aviation 3 Future Aviation Fuel The long term availability of fossil fuels cannot be guaranteed. As fossil fuel become scarce, the price will increase and alternative fuels may be used. In the medium term biofuels offer an attractive option. In the long term, Hydrogen or Liquid Natural Gas seems the most attractive option. Kerosene Synthetic fuel / GTL/CTL/Biofuels LNG/ Hydrogen Aircraft Primary Energy Source Electric Kerosene Synthetic fuel / GTL/CTL/Biofuels LNG/ Hydrogen LNG/ Hydrogen Aircraft Primary Energy Source Electric 4 Cryogenic Fuels (LNG & LH2) The mass energy density of Hydrogen is much higher than of kerosene, so less fuel is needed. But the volume is much higher as well and the liquid has to be cooled. LNG mass density is slightly better than kerosene but it also requires special storage tanks. 5 Storage of Cryogenic Fuels Storage of LNG and Hydrogen requires large low temperature tanks. Initial configuration studies proved to be unattractive as drag would be increased, thus increasing the fuel burn. New configurations are needed. 6 Storage of Cryogenic fuels in a Multi fuel BWB LH2/LNG tanks Kerosene/ Biofuels BWB has inherently has extra volume which can be used to accommodate the cylindrical fuel tanks This novel idea of multi fuel BWB is unique which optimizes the usage of space in a BWB 7 LNG/ LH2 Main Combustor Kerosene/ Biofuel Secondary Flameless Combustor Bleed cooling by LH2 Counter rotating shrouded fans Higher Specific Thrust Low Installation Penalty Next generation hybrid engine 8 Overview of the workpackage structure Conceptual Configuration WP2: Dual Hybrid combustion system Environmental Assessment and Integration Dissemination : Management Technical Solutions Assessment and Final Configuration Outreach 9 Multi Fuel Blended Wing Body Design The main task in this WP is to do the conceptual design of the multi- fuel blended wing body aircraft 10 Optimization procedure Modules Preliminary design 11 Novel Configuration Multi fuel Blended Wing Body TU Delft proposes a Blended Wing Body configuration combined with a slender wing for a very efficient new aircraft that would replace the Boeing 777 or Airbus 340. It incorporates 3 fuel tanks without substantial drag penalty. 12 Preliminary design = 24.2 = 0.305 = 0.0018 ref = 900 m 2 Aerodynamics L D 13 Preliminary design Materials: Carbon Fiber Reinforced Polymer Main structure Elliptical frames Ribs Bulkheads Structures (1) 14 Preliminary design Stability: Canards Winglets Control: Variable camber canard Elevons Winglet rudders Stability and Control 15 Preliminary design New-BWB 242,800 kg MTOW 237,970 122,220 kg 265.04 (T/W) 0.21 527,810 N cruise 98,195 N Weight breakdown 16 The Bleed Cooling system The main task of this task is to design a cooling system to cool the bleed air with the cryogenic 17 17 Van Dijk, I.P.,Rao, G.A and Buijtenen, J.P, “A Novel Technique of Using LH2 in Gas Turbine Engines”, ISABE 2009 , Sept 7-11, Montreal, ISABE 2009- Use of Cryogenic fuel as a heat sink Using the cryogenic fuel to cool the bleed air is the best way of improving the thermal efficiency of a turbofan engine Stator coolingHeat exchanger in duct Colder turbine cooling bleed Airco system link Reduction in fuel consumption Increase in Specific Thrust Performance overview for all studied cycle 18 Aim and objectives The specific objectives of this work package are to: To study and analyze suitable techniques / methodology that could be used for cooling the bleed Preliminary design of the heat exchange system between the bleed air and LH2 To perform the sizing of the various components within the hybrid engine in order to obtain the approximate dimensions of the hybrid engine. To estimate the overall weight of the hybrid engine 19 D project based on baseline engine LH2 Storage Designed Heat Exchanger LH2 FMM H2 Combustor Inter Turbine Flameless Combustor Design of the cryogenic fuel to air heat exchanger 20 Project development tree : Basic model Rejected due to high stress between compartments Rejected due to Rejected due to 21 The hydrogen combustion chamber The aim of this task is to design the primary combustor for the hybrid engine using hydrogen as 22 Axial injection controlled by mass flow meter Impact of axial injection: Increases axial velocity at outlet Downstream shift of central recirculation zone Increasing axial injection ( in % ) 0 7.5 Axial Injection - PIV in Water Tunnel desired flow field tot VV 23 Combustion Test Rig Gas-fired tests with 100% hydrogen with axial injection on the TUB combustion test trig 24 Moveable Block (MB) burner: Large mixing length Lm=170mm Pressure loss 10% New burner: Reduced mixing length Long = 100mm Short = 80mm Pressure loss 3- =170mm =80mm Air Air Fuel Fuel Reduced Dimensions Approaching an Applicable Design 25 Atmospheric conditions: new burner exhibits wide operational range without any flashback occurance Fired Tests: Stability Map 0 0,2 0,4 0,6 0,8 1 1,2 0 100 200 300 400 500 Equivalence Ratio T preheat Operability range of new burner (u 0 =35 - 120 m/s) HP, m=130kg/h, S=0.9, 8.8mm, longMT HP LBO, m=130kg/h, S=0.9, 8.8mm, longMT No flashback Not tested Lean blow out 26 emissions increase with inlet temperature Tin Below 20 for all Tin at design equivalence ratio of φ≈0.4 -0.55 NOx T in S=0.9 and 27 The Inter Turbine Flameless Combustion Chamber The main aim of this task is to design and validate the secondary inter- turbine flameless combustion chamber for the AHEAD hybrid engine 28 Different Combustion Regimes Flameless combustion CHARACTERISTICS Recirculation combustion products high temperature Reduced oxygen concentration the reactants Highly transparent flame with low acoustic oscillation Distributed combustion zone Uniform temperature distribution Reduced temperature peaks Low adiabatic flame temperature High concentration 2 & H2O Lower Damköhler number and emission Comparison between a conventional combustion and Flameless Combustion (Wünning and Wünning, 2003 ) 29 Evaluated combustor configurations for the Inter Turbine Flameless combustion Chamber 30 recirculated ultra lean combustor version #2 31 CFD for liquid fuel injection Left picture shows more significant evaporation process 32 Climate Impact Assessment of the Multi-Fuel BWB Aircraft The primary aim of this task is to analyse the effect of changing aircraft emissions on the global climate due to the use of multi-fuel BWB with hybrid 33 0.031 0.074 Climate impact of current air traffic (2005) 34 Global climate impact of contrail cirrus Change in climate impact contrail cirrus Change in formation conditions (aircraft related) Change in soot emissions Change in coverage and microphysical properties contrail cirrus Change in flight level 35 Change in formation conditions II Implications for contrail formation (2) AHEAD BWBs will produce contrails in a deeper atmospheric layer than conventional aircraft because the threshold temperatures are higher (i.e. formation starts at lower altitude). 36 upward shift - base case downward shift - base case Changes in contrail cirrus RF due to changes in flight level - decrease of RF in mid latitudes, - increase in tropics/subtropics, - globally +4 2 (~9%) - increase of RF in mid latitudes, -decrease in tropics/subtropics, - globally - 37 Change in contrail cirrus radiative due to a replacement of conventional planes 2 planes level (LH conventional forcing increased contrail radiative level planes 2000 LH Contrail radiative nearly everywhere decreased version AHEAD aircraft Contrail cirrus radiative forcing - change in formation + shift of flight level by ~ 2000m 38 Change in contrail cirrus radiative due to a replacement of conventional planes by LNG planes an increase in flight level by 2000m (LNGup3 -- conventional). cirrus forcing increased (factor particularly south of 45 N relative to conventional air traffic. ncreases smaller than for LH2 planes. in contrail cirrus radiative due a shift in flight level LNG planes by ~ 2000m (LNGup3 LNG) Contrail cirrus radiative reduced in places. LNG version of AHEAD aircraft: Contrail - formation conditions + shift of flight level by ~ 2000m 39 Hybrid Engine Performance 40 Model The model was validated with GSP Ambient Condition Nozzle Cooling Inter burner LP Turbine Inlet Fan & Booster Cp, gamma, R Composition Gas Properties Pt, Tt Fraction Air Properties Air Properties Cp, gamma, R Cp, gamma, R Composition Gas Properties Composition Gas Properties Fraction Cp, gamma, R Cp, gamma, R Composition Gas Properties Cp, gamma, R Pt, Tt Composition Gas Properties Cp, gamma, Fraction Engine Performance bypass 41 The Engine Model in GSP Inter-stage Turbine Burner Main Combustion Chamber 42 Comparison of hybrid engine with GE SFC SFC SEC 43 Comparison of hybrid engine with PW4056 SFC SEC 44 Conclusion Comparison with B777-200ER (1) 45 Comparison with B777-200ER (2) 46 Emission range 14000 km Aircraft Reduction (%) KgCO2/(km*k g) Payload (kg) Passengers kgCO2/(Pas senger*km) B777 65.41 0.0014189 22478 186 0.172 A330 89.267 0.0045728 5737.1 48 0.554 B787 42.913 0.00085974 28985 239 0.104 BWB 0 0.0004908 36400 300 0.059 47 The AHEAD Aircraft 48 Advanced Hybrid Engines for Aircraft Development Delft University of Technology WSK PZL-Rzeszow S.A Technical University of Berlin DLR, IPA Israel Institute of Technology- Technion Cuenta b.v. 49 Dr. Arvind Rao Delft University of Technology Flight Performance and Propulsion T: +31 (0)15 27 83833 E: [email protected] Kluyverweg 1 Delft The Netherlands www.ahead- euproject.eu This project receives funding from the European Union's Seventh Framework Programme under grant agreement nr 284636