Future propulsion engineering: hybrid-electric, hydrogen and open rotor — the numbers that decide them
What decides a new propulsion concept: energy per kilogram and per litre, the mass of motors, tanks and fuel cells, the efficiency of the whole chain, and the certification route. Hybrid-electric architectures, hydrogen combustion and fuel cells, the open rotor, special conditions and an official investigation. Part 4 of the Propulsion engineering series.
What you will be able to do
- ✓ Compare jet fuel, batteries and hydrogen by energy per kilogram and per litre, and calculate the mass and volume each needs for a sector.
- ✓ Distinguish NASA's electrified propulsion architectures and interpret the power, mass, efficiency and voltage figures of electric machines.
- ✓ Explain hydrogen combustion and fuel cells, size a liquid hydrogen tank, and describe the airport supply problem.
- ✓ Explain the open rotor's propulsive efficiency gain and its certification and installation trade-offs, as tested and proposed.
- ✓ Describe the certification routes for new propulsion: FAA special conditions, EASA SC E-19 and the FAA hydrogen roadmap.
- ✓ Draw lessons from an official investigation of an experimental hydrogen-electric aircraft and connect the four parts of the series.
Course content
Session 1 · What decides a new propulsion concept
1.1
- Four numbers that decide a new propulsion concept · free preview
- Energy per kilogram and per litre
- From tank to thrust: efficiency and mass
- Worked example: one sector, three energy stores
Session 2 · Hybrid-electric propulsion
1.2
- Hybrid-electric architectures
- Electrical machines and power electronics: the numbers
- Where hybrids help, and the demonstrators
- Worked example: is a take-off boost worth carrying?
Session 3 · Hydrogen: combustion, fuel cells and storage
1.3
- Hydrogen: burn it or convert it
- Storing liquid hydrogen on board
- Hydrogen at the airport
- Worked example: sizing the hydrogen tank
Session 4 · Open rotor and open fan
1.4
- Why a bigger fan: propulsive efficiency again
- What the tests showed: the FAA CLEEN open rotor programme
- Installing and certifying an open rotor
- Worked example: how much can a bigger fan save?
Session 5 · Certification pathways for new propulsion
1.5
- A rule book written for fuel: the FAA's special conditions
- EASA's Special Condition SC E-19 and the first certified electric engine
- Hydrogen and the regulators
- Worked example: mapping a certification basis
Session 6 · Choosing a concept, and the investigation file
1.6
- Putting the numbers together: which concept for which aircraft?
- Beyond carbon dioxide: nitrogen oxides, water and contrails
- One aircraft, four views: closing the series
- From the investigation file: a hydrogen fuel cell test aircraft, 2021
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Who this course is for
- Propulsion, systems and design engineers at manufacturers, suppliers and start-ups who assess hybrid-electric, hydrogen or open rotor concepts and need the numbers behind them
- Fleet planning, technical and sustainability specialists at airlines, airports and lessors who must judge claims about new propulsion, energy supply and entry-into-service dates
- Certification and airworthiness specialists who need to understand FAA special conditions, EASA SC E-19, the FAA hydrogen roadmap and the open rotor proposals
You need: Part 3 of this series or equivalent knowledge of engine certification; Parts 1 and 2 are useful for efficiency and emissions; comfort with unit conversions, percentages and simple energy calculations.
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