AAE-E3050 Bioenergy and Biofuels, Transport biofuels Yuri Kroyan September 2019 Lecture: Sustainable Aviation Fuels Agenda
1. History of Jet engines 2. Jet engines – how do they work 3. Ideal turbojet cycle – the performance of a jet turbine. 4. Various designs of jet turbines 5. Aviation Fuels, important properties and additives 6. Short quiz 7. Aviation before, now and in the future 8. Sustainable aviation fuels and their current commercial status 9. Interesting state-of-the-art conversion pathways 10. Few interesting facts about 1st generation biomass What laws of nature drive jet engines? Sir Isaac Newton (25 December 1642 – 20 March 1727) Newton’s Laws of Motion
1. „Every object presists in its state of rest or uniform motion in a straigh line unless it is compelled to change that state by forces impressed on it” 2. „Force is equal to change in momentum (mV) per change in time. For a constant mass, force equals mass times acceleration F=ma” 3. „For every action, there is an equal and opposite re-action” https://www.youtube.com/watch?v=3FyhNpHeHMM Jet engines - how do they work?
https://www.youtube.com/watch?v=KjiUUJdPGX0 Ideal turbojet cycle
Efficiency Typical values Thermal 5% - 50% Propulsive 5% - 40% Combustion 90% - 99%
휂표푣푒푟푎푙푙 = 휂푡ℎ푒푟푚푎푙 ∙ 휂푝푟표푝푢푙푠𝑖푣푒
푁푒푡 푝표푤푒푟 표푢푡푝푢푡 푇0 푇ℎ푟푢푠푡 ∙ 퐹푙𝑖푔ℎ푡 푣푒푙표푐𝑖푡푦 퐹 ∙ 푉0 휂푡ℎ푒푟푚푎푙 = = 1 − 휂푝푟표푝푢푙푠𝑖푣푒 = = 푇ℎ푒푟푚푎푙 푒푛푒푟푔푦 푎푣푎𝑖푙푎푏푙푒 𝑖푛 푡ℎ푒 푓푢푒푙 푇3 푇표푡푎푙 푝표푤푒푟 표푢푡푝푢푡 푊ሶ 표푢푡 How to increase the performance of the Jet-engine?
• Increasing the thermal efficiency by larger compressor pressure ratio. • Incrasing the power-output to engine weight, by for example increasing the turbine inlet temperature. Different designes of the gas turbines dependent on the application.
1. Turbojet pioneer design
2. Turboprop (turbine engine that drives an aircraft propeller)
3. Turboshaft (electric generation)
4. High-bypass turbofan (applied in the most of the present day commercial aircrafts)
5. Low-bypass afterburning turbofan (mostly used for military supersonic aircrafts) Low-bypass afterburning turbofan When passing the supersonic bareer The white cloud is formed by decreased air pressure and temperature around the tail of the aircraft What happens when passing Mach 1?
https://www.youtube.com/watch?v=G87ciaWw2O4 Michal Wojcieszyk ([email protected]) Regular fuels used for Source: ExxonMobil commercial aviation The most commonly used fuels are Jet A and Jet A-1 – fossil fuel (kerosene type).
• Jet A-1 International standard • Jet A Normally available only in U.S.A
• Jet B Military application. It is so called naphta-kerosene (30% kerosene and 70% gasoline). It has enhanced cold- weather performance, very low freezing point of −60 °C, and low flash point. Jet B has lighter composition, therefore it is more dangerous to handle – higher flammability.
https://www.exxonmobil.com/en/aviation/products-and-services/products/jet-a-jet-a-1 Jet fuels (kerosese) typical boiling range 150 – 260℃
http://caafi.org/resources/pdf/3.2_SAJF_Benefits.pdf
https://i.pinimg.com/originals/70/bb/e0/70bbe04171bef01ab74fd4ca2e4c05dc.png Crucial fuel properties in specifications
ASTM D1655 Standard Specification for Aviation Turbine Fuels
https://www.fire.tc.faa.gov/pdf/TG67.pdf Important fuel properties and additives for operation and safety Flash point, autoignition temperature and fire point
• Flash point is the lowest temperature at which vapours of the fuel will ignite when given an ignition source. • Autoignition temperature is the lowest temperature that initiate spontaneous ignition. • Fire point is the lowest themperature that vapours of fuel will keep burning after the ignition source is removed. At fire point, the vapor is produced fast enough to sustain the combustion.
푇퐹푙푎푠ℎ 푝표𝑖푛푡 < 푇퐴푢푡표𝑖𝑔푛𝑖푡𝑖표푛 < 푇퐹𝑖푟푒 푝표𝑖푛푡 Freezing point
The lowest temperature at which the fuel remains free of solid hydrocarbon crystals.
The temperature of the fuel in the aircraft tank is decreasing during the flight, altitude, and flight duration. Therefore, the freezing point of the fuel must always be lower than the minimum operational tank temperature. Cristalised fuel can restrict the http://www.skybrary.aero/ flow of fuel through filters and cause operational problems. Jet fuel additives
Antioxidants to prevent formation of gums, usually based on alkylated phenols, e.g., AO-30, AO-31, or AO-37; Antistatic agents (conductivity improvers), to prevent static discharges of accumulated electricity in the fuel. Stadis 450, with dinonylnaphthylsulfonic acid (DINNSA) as a component, is an example. Corrosion inhibitors, e.g., DCI-4A used for civilian and military fuels, and DCI-6A used for military fuels; Fuel system icing inhibitor (FSII) agents, e.g., Di-EGME; FSII is often mixed at the point-of-sale so that users with heated fuel lines do not have to pay the extra expense. Biocides are to remediate microbial (i.e., bacterial and fungal) growth present in aircraft fuel systems. Currently, two biocides are approved for use by most aircraft and turbine engine original equipment manufacturers (OEMs); Kathon FP1.5 Microbiocide and Biobor JF. Metal deactivator can be added to reduce the negative effects of trace metals on the thermal stability of the fuel. Metals (such as copper) are catalyzing oxidation of the fuel, even at very low temperatures (metals can cause the fail of Jet Fuel Thermal Oxidation Test – JFTOT). The one allowable additive is the chelating agent salpn (N,N′-bis(salicylidene)-1,2-propanediamine). Aviation before, now and in the future Three questions:
• Do you have a bad consience on the climate impact when you book a flight? [Yes, no opinion, No]
• Would you choose the less CO2 emitting flight, when the tickets are 10%, 20%, 30% more expensive ? [Yes, No]
• Have you in the past offsett (part of) the CO2 emissions linked to a flight? [Yes, No] Map of the World’s Air Traffic Connections Map of the World’s Air Traffic Connections Aviation is a number ONE if it comes to the growth! Aviation - sector specific targets Aviation (both domestic and international) is responsible for 2% of global GHG emissions. In 2009, the aviation industry collectively agreed to the world‟s first set of sector-specific climate change targets. CORSIA - Carbon Offsetting and Reduction Scheme for International Aviation
Source: https://www.icao.int/environmental-protection/CORSIA/Documents/CORSIA%20Brochure/CorsiaBrochure_ENG-Mar2019_Web.pdf CORSIA - Carbon Offsetting and Reduction Scheme for International Aviation https://www.youtube.com/watch?v=OUfhLkMhc8w&feature=youtu.be
Need of liquid fuels vs electrification
Electrification Need of liquid fuels liquid of Need ASTM D7566
2009 2011 2014 2015 2016
Synthetic paraffinic Sythetic paraffinic Hydroprocessed Alcohol-to-jet from Synthesized iso- kerosene with kerosene via Fisher esters and fatty i-butanol (2016) paraffins (SIP) aromatics via Fisher Tropsch acids (HEFA) and ethanol (2018) Tropsch
Fuels that comply with D7566 are automatically recognized as meeting the ASTM D1655 specification for conventional jet fuel (i.e. can be used as jet fuel without restrictions)
https://www.iata.org/whatwedo/environment/Documents/safr-1-2015.pdf Limitations
Current commercial status of SAF December 2018
OVER
Flights using SAF
https://www.iata.org/pressroom/facts_figures/fact_sheets/Documents/corsia-fact-sheet.pdf Regularly distributing SAF
Oslo (Lufthansa, KLM, SAS, KLC), LAX (United and KLM), Stockholm (SAS, KLM, BRA), Bergen (all departures).
Additionally, batches have been delivered to: Stockholm Bromma, Are Ostersund, Goteborg, Karlstad, Halmstad, Brisbane, Chicago.
https://www.iata.org/pressroom/facts_figures/fact_sheets/Documents/corsia-fact-sheet.pdf Approximate amount of SAF produced in 2017
Agreements from commercial airlines to purchase SAF in the future
https://www.iata.org/pressroom/facts_figures/fact_sheets/Documents/corsia-fact-sheet.pdf Interesting state-of-the-art conversion pathways https://www.lanzatech.com https://www.lanzatech.com https://www.lanzatech.com https://www.lanzatech.com https://www.lanzatech.com Few interesting facts about 1st generation biomass
Thank you for your attention!
Yuri Kroyan Doctoral Candidate [email protected]