Periodic Reporting for period 1 - TRIATHLON (THERMODYNAMICS-DRIVEN CONTROL MANAGEMENT OF HYDROGEN POWERED AND ELECTRIFIED PROPULSION FOR AVIATION)
Okres sprawozdawczy: 2024-01-01 do 2025-06-30
In order to mitigate the negative impact of human activity on the environment, significant efforts to lower carbon emissions are being pursued at both the global and European levels. Globally, the aviation industry aims for a 50% reduction of its carbon emissions by 2050, relative to 2005. In this transition towards net zero carbon emissions, novel powertrain technologies exploiting fuel cells and/or combustion systems that rely on hydrogen will play a significant role. TRIATHLON will use the synergy between powertrain components to overcome the challenges associated with scaling up hydrogen powertrain technology to MW class. The ambition of TRIATHLON is the development of disruptive approaches to design more robust, low-maintenance, low-emmision, highly responsive hydrogen-electric powertrains for megawatt class aircraft. When the distruptive technologies developed by TRIATHLON are adopted by the industry beyond TRIATHLON, it will lead to:
1) Reduction of emissions by implementation of NOx reduction strategies like injection of exhaust water of the FC into the CC and by capturing vented and permeated hydrogen and recompressing it;
2) Elimination of the need for a cryogenic pump by using a high-pressure storage buffer for pressurisation of the fuel distribution system (making the fuel distribution more robust for turbulence as well);
3) Reduction of the power required for hydrogen conditioning using excess heat from FC and CC by means of 3D printed heat exchangers using innovative materials like ceramics, and smart thermal management;
4) Improvement of the gravimetric index of the entire powertrain by providing an effective heatsink to powertrain components, reducing the need for coolant, allowing design of a more compact and lightweight CC, as well as the need for insulation of the hydrogen storage whilst enabling a longer dormancy time.
1) Reduction of emissions by implementation of NOx reduction strategies like injection of exhaust water of the FC into the CC and by capturing vented and permeated hydrogen and recompressing it;
2) Elimination of the need for a cryogenic pump by using a high-pressure storage buffer for pressurisation of the fuel distribution system (making the fuel distribution more robust for turbulence as well);
3) Reduction of the power required for hydrogen conditioning using excess heat from FC and CC by means of 3D printed heat exchangers using innovative materials like ceramics, and smart thermal management;
4) Improvement of the gravimetric index of the entire powertrain by providing an effective heatsink to powertrain components, reducing the need for coolant, allowing design of a more compact and lightweight CC, as well as the need for insulation of the hydrogen storage whilst enabling a longer dormancy time.
The TRIATHLON project containts four technical workpackages (WP): WP1 Hydrogen Conditioning Requirements, WP2 Thermodynamics Controlled Storage, WP3 Thermal Management and Thermondynamic Performance and WP4 System-Level Analysis and Technology Roadmap.
After an extensive literature review, it was decided to focus on High Temperature Proton Exchange Membrane fuel cells (HT-PEMFC) in WP1. High-fidelity Ansys Fluent simulations were compared with validations found in literature. Based on the results, it was decided to focus on thermal power dissipation to the environment. It was considered where power should be rejected to the environment of the aircraft, and a choice was made for the underfloor bay. Work is on-going regarding the CFD characterization of the HT-PEMFC heat-rejection environment, as well as the synergies between powertrain components needing to receive or reject heat respectively.
Simultaneously, a reference combustion system for WP1 was found in the FlyECO concept design. High-fidelity simulations employing the in-house OpenFOAM tFDF-ESF solver of TU Delft, were performed with the objective to optimize the combustor design. The first results are promising in terms of NOx reduction, but further optimization is needed. Water injection could help with this.
In WP2, a generic tank sizing tool was developed and validated. Two reference flight profiles for a megawatt-class aircraft were selected: ATR 72-600 and Novacom. The storage size for a cryo-compressed storage tank and subsequent hydrogen mass flows for the respective flight profiles were estimated and the ensuing thermodynamic performance of the storage tank was analyzed. Simultaneously a new approach to high-fidelity damage modelling of a fully composite pressure tank has been developed to predict crack formation in the laminate, which can then be linked to permeability of the tank wall. A new test rig for permeation tests of the composite tank wall was developed as well.
In WP3 ceramic coupons with different materials and geometric properties were 3D printed. A numerical analysis was made of the expected flow through the coupons at different Reynolds numbers, as well as the expected thermal behaviour. A test-rig to perform the single- and two-phase experiments was developed and the first set of experiments on this test-rig has almost been completed. The results will be used for the production of a second batch of coupons.
In WP4 a literature and market review of hydrogen powertrains for megawatt class aircraft have been performed. Next to that, a model of the entire powertrain has been created using Matlab and Simulink, effectively combining the other three technical work packages. And a beginning of a technology roadmap has been made, to predict future developments needed to bring the technology developed in TRIATHLON to fruition.
After an extensive literature review, it was decided to focus on High Temperature Proton Exchange Membrane fuel cells (HT-PEMFC) in WP1. High-fidelity Ansys Fluent simulations were compared with validations found in literature. Based on the results, it was decided to focus on thermal power dissipation to the environment. It was considered where power should be rejected to the environment of the aircraft, and a choice was made for the underfloor bay. Work is on-going regarding the CFD characterization of the HT-PEMFC heat-rejection environment, as well as the synergies between powertrain components needing to receive or reject heat respectively.
Simultaneously, a reference combustion system for WP1 was found in the FlyECO concept design. High-fidelity simulations employing the in-house OpenFOAM tFDF-ESF solver of TU Delft, were performed with the objective to optimize the combustor design. The first results are promising in terms of NOx reduction, but further optimization is needed. Water injection could help with this.
In WP2, a generic tank sizing tool was developed and validated. Two reference flight profiles for a megawatt-class aircraft were selected: ATR 72-600 and Novacom. The storage size for a cryo-compressed storage tank and subsequent hydrogen mass flows for the respective flight profiles were estimated and the ensuing thermodynamic performance of the storage tank was analyzed. Simultaneously a new approach to high-fidelity damage modelling of a fully composite pressure tank has been developed to predict crack formation in the laminate, which can then be linked to permeability of the tank wall. A new test rig for permeation tests of the composite tank wall was developed as well.
In WP3 ceramic coupons with different materials and geometric properties were 3D printed. A numerical analysis was made of the expected flow through the coupons at different Reynolds numbers, as well as the expected thermal behaviour. A test-rig to perform the single- and two-phase experiments was developed and the first set of experiments on this test-rig has almost been completed. The results will be used for the production of a second batch of coupons.
In WP4 a literature and market review of hydrogen powertrains for megawatt class aircraft have been performed. Next to that, a model of the entire powertrain has been created using Matlab and Simulink, effectively combining the other three technical work packages. And a beginning of a technology roadmap has been made, to predict future developments needed to bring the technology developed in TRIATHLON to fruition.
TRIATHLON is expected to deliver the knowledge for a fully integrated hydrogen powertrain for a megawatt class aircraft in which the synergy between combustion chambers and fuel cells brings an improvement in powertrain efficiency as well as performance. The multi-state storage system is expected to reduce the overall complexity of the hydrogen powertrain, by reducing or eliminating the need for in-tank heat exchangers and/or cryogenic pumps, by relying on balance of plant parts instead. Beter prediction of crack-formation will enable better design of a fully composite storage tank with acceptable levels of permeation. And, a better understanding of the powertrain control will reduce the need the coolant flow rate, and the more optimized design of the remaining heat exchangers, combined with the aforementioned improvements, will make for an overall significantly lighter powertrain.