scholarly journals Reduced ice number concentrations in contrails from low aromatic biofuel blends

2021 ◽  
Author(s):  
Tiziana Bräuer ◽  
Christiane Voigt ◽  
Daniel Sauer ◽  
Stefan Kaufmann ◽  
Valerian Hahn ◽  
...  
Keyword(s):  
Radiative Forcing ◽  
Measurement Data ◽  
Climate Impact ◽  
Aviation Fuel ◽  
Fuel Blend ◽  
Extinction Coefficients ◽  
Flight Experiment ◽  
Maximum Reduction ◽  
Aromatic Content ◽  
Fuel Jet

Abstract. Sustainable aviation fuels can reduce contrail ice numbers and radiative forcing by contrail cirrus. We measured apparent ice emission indices for fuels with varying aromatic content at altitude ranges of 9.1–9.8 km and 11.4–11.6 km. Measurement data were collected during the ECLIF II/NDMAX flight experiment in January 2018. The fuels varied in both aromatic quantity and type. Between a sustainable aviation fuel blend and a reference fuel Jet A-1, a maximum reduction in apparent ice emission indices of 40 % was found. We show vertical ice number and extinction distributions for three different fuels and calculate representative contrail optical depths. Optical depths of contrails (0.5–3 minutes in age) were reduced by 40 to 52 % for a sustainable aviation fuel compared to the reference fuel. Our measurements suggest that sustainable aviation fuels result in reduced ice particle numbers, extinction coefficients, optical depth and climate impact from contrails.

scholarly journals Reduced ice number concentrations in contrails from low-aromatic biofuel blends

2021 ◽  
Vol 21 (22) ◽  
pp. 16817-16826
Author(s):  
Tiziana Bräuer ◽  
Christiane Voigt ◽  
Daniel Sauer ◽  
Stefan Kaufmann ◽  
Valerian Hahn ◽  
...  
Keyword(s):  
Radiative Forcing ◽  
Measurement Data ◽  
Climate Impact ◽  
Aviation Fuel ◽  
Fuel Blend ◽  
Extinction Coefficients ◽  
Flight Experiment ◽  
Maximum Reduction ◽  
Aromatic Content ◽  
Fuel Jet

Abstract. Sustainable aviation fuels can reduce contrail ice numbers and radiative forcing by contrail cirrus. We measured apparent ice emission indices for fuels with varying aromatic content at altitude ranges of 9.1–9.8 and 11.4–11.6 km. Measurement data were collected during the ECLIF II/NDMAX flight experiment in January 2018. The fuels varied in both aromatic quantity and type. Between a sustainable aviation fuel blend and a reference fuel Jet A-1, a maximum reduction in apparent ice emission indices of 40 % was found. We show vertical ice number and extinction distributions for three different fuels and calculate representative contrail optical depths. Optical depths of contrails (0.5–3 min in age) were reduced by 40 % to 52 % for a sustainable aviation fuel compared to the reference fuel. Our measurements suggest that sustainable aviation fuels result in reduced ice particle numbers, extinction coefficients, optical depth and climate impact from contrails.

The Effect of TiO2 on Engine Emissions for Gas Turbine engine Fueled with jatropha, butanol, Soya and Rapeseed Oil

2020 ◽  
Vol 37 (1) ◽  
pp. 85-94 ◽  
Author(s):  
P. Booma Devi ◽  
D. Raja Joseph ◽  
R. Gokulnath ◽  
S. Manigandan ◽  
P. Gunasekar ◽  
...  
Keyword(s):  
Methyl Ester ◽  
Gas Turbine ◽  
Gas Turbine Engine ◽  
Aviation Fuel ◽  
Fuel Blend ◽  
High Oxygen Content ◽  
Turbine Engine ◽  
Micro Gas Turbine ◽  
Fuel Blends ◽  
Fuel Jet

AbstractThis paper aims in assessing the effect of biofuel blend such as butanol, jatropha methyl ester, soya methyl ester and rapeseed methyl ester as an additive for the aviation fuel. In addition to the blends, the nanoparticle TiO2 of 3 % is added to the biofuel. The nanoparticle mixed at the concentration of 300ppm by ultrasonication process. The fuel Jet A, B27T, J27T, S27T and R27T are investigated for combustion and emission characteristics for various throttle settings in micro gas turbine engine. Addition of additives improves the ultimate property of the fuel by reducing the kinematic viscosity. The fuel blend B27T reports 25 % increase in total static thrust and 22 % reduction in thrust specific fuel consumption. From the results it is evident that, all fuel blends showed a significant reduction in emission values owing to high oxygen content. In addition, the thermal efficiency of the B27T and J27T is improved appreciably to 30 % and 10 % higher than Jet A fuel owing to the influence of the nanoparticle TiO2. On the other hand, the emissions like CO and NOx reduced drastically up to 70 % and 45 % respectively.

scholarly journals The global impact of the transport sectors on atmospheric aerosol in 2030 – Part 1: Land transport and shipping

2014 ◽  
Vol 14 (16) ◽  
pp. 22985-23025
Author(s):  
M. Righi ◽  
J. Hendricks ◽  
R. Sausen
Keyword(s):  
Atmospheric Aerosol ◽  
Radiative Forcing ◽  
Global Climate ◽  
Climate Impact ◽  
Radiation Budget ◽  
Intergovernmental Panel ◽  
Surface Level ◽  
Aerosol Module ◽  
Year 2000 ◽  
The Impact

Abstract. Using the EMAC global climate-chemistry model coupled to the aerosol module MADE, we simulate the impact of land transport and shipping emissions on global atmospheric aerosol and climate in 2030. Future emissions of short-lived gas and aerosol species follow the four Representative Concentration Pathways (RCPs) designed in support of the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. We compare the resulting 2030 land-transport- and shipping-induced aerosol concentrations to the ones obtained for the year 2000 in a previous study with the same model configuration. The simulations suggest that black carbon and aerosol nitrate are the most relevant pollutants from land transport in 2000 and 2030, but their impacts are characterized by very strong regional variations during this time period. Europe and North America experience a decrease in the land-transport-induced particle pollution, although in these regions this sector remains the dominant source of surface-level pollution in 2030 under all RCPs. In Southeast Asia, on the other hand, a significant increase is simulated, but in this region the surface-level pollution is still controlled by other sources than land transport. Shipping-induced air pollution is mostly due to aerosol sulfate and nitrate, which show opposite trends towards 2030. Sulfate is strongly reduced as a consequence of sulfur reduction policies in ship-fuels in force since 2010, while nitrate tends to increase due to the excess of ammonia following the reduction in ammonium-sulfate. The aerosol-induced climate impact of both sectors is dominated by aerosol-cloud effects and is projected to decrease between 2000 and 2030, nevertheless still contributing a significant radiative forcing to the Earth's radiation budget.

scholarly journals Transport of the 2017 Canadian wildfire plume to the tropics via the Asian monsoon circulation

2019 ◽  
Vol 19 (21) ◽  
pp. 13547-13567 ◽  
Author(s):  
Corinna Kloss ◽  
Gwenaël Berthet ◽  
Pasquale Sellitto ◽  
Felix Ploeger ◽  
Silvia Bucci ◽  
...  
Keyword(s):  
Radiative Forcing ◽  
Asian Monsoon ◽  
Regional Climate ◽  
Climate Impact ◽  
Monsoon Circulation ◽  
Aerosol Layer ◽  
Fire Plume ◽  
Monsoon Area ◽  
The Tropics ◽  
The Impact

Abstract. We show that a fire plume injected into the lower stratosphere at high northern latitudes during the Canadian wildfire event in August 2017 partly reached the tropics. The transport to the tropics was mediated by the anticyclonic flow of the Asian monsoon circulation. The fire plume reached the Asian monsoon area in late August/early September, when the Asian monsoon anticyclone (AMA) was still in place. While there is no evidence of mixing into the center of the AMA, we show that a substantial part of the fire plume is entrained into the anticyclonic flow at the AMA edge and is transported from the extratropics to the tropics, and possibly the Southern Hemisphere particularly following the north–south flow on the eastern side of the AMA. In the tropics the fire plume is lifted by ∼5 km in 7 months. Inside the AMA we find evidence of the Asian tropopause aerosol layer (ATAL) in August, doubling background aerosol conditions with a calculated top of the atmosphere shortwave radiative forcing of −0.05 W m−2. The regional climate impact of the fire signal in the wider Asian monsoon area in September exceeds the impact of the ATAL by a factor of 2–4 and compares to that of a plume coming from an advected moderate volcanic eruption. The stratospheric, trans-continental transport of this plume to the tropics and the related regional climate impact point to the importance of long-range dynamical interconnections of pollution sources.

scholarly journals On the Life Cycle of Individual Contrails and Contrail Cirrus

2017 ◽  
Vol 58 ◽  
pp. 3.1-3.24 ◽  
Author(s):  
Ulrich Schumann ◽  
Andrew J. Heymsfield
Keyword(s):  
Life Cycle ◽  
Radiative Forcing ◽  
Ambient Pressure ◽  
Climate Impact ◽  
Particulate Emissions ◽  
Particle Sedimentation ◽  
Ice Clouds ◽  
Surface Warming ◽  
Model Studies ◽  
Ice Particles

Abstract The life cycle of individual (initially line shaped) contrails behind aircraft and of contrail cirrus (aged contrails mixed with other ice clouds) is described. The full contrail life cycle is covered, from ice formation for given water, heat, and particulate emissions; to changes in the jet, wake, and dispersion phases; through final sublimation or sedimentation. Contrail properties are deduced from various in situ, remote sensing, and model studies. Aerodynamically induced contrails and distrails are explained briefly. Contrails form both in clear air and inside cirrus. Young contrails consume most of the ambient ice supersaturation. Optical properties of contrails are age and humidity dependent. Contrail occurrence and radiative forcing depends on the ambient Earth–atmosphere conditions. Contrail cirrus seems to be optically thicker than assessed previously and may not only increase cirrus coverage but also thicken existing cirrus. Some observational constraints for contrail cirrus occurrence and radiative forcing are derived. Key parameters controlling contrail properties—besides aircraft and fuel properties, ambient pressure, temperature, and humidity—are the number of ice particles per flight distance surviving the wake vortex phase, the contrail depth, and particle sedimentation, wind shear, turbulence, and vertical motions controlling contrail dispersion. The climate impact of contrails depends among other things on the ratio of shortwave to longwave radiative forcing (RF) and on the efficacy with which contrail RF contributes to surface warming. Several open issues are identified, including renucleation from residuals of sublimated contrail ice particles.

An Ignition Delay Study of Category A and C Aviation Fuel

2015 ◽  
Author(s):  
Kyungwook Min ◽  
Daniel Valco ◽  
Anna Oldani ◽  
Tonghun Lee
Keyword(s):  
Ignition Delay ◽  
Cetane Number ◽  
Test Chamber ◽  
Combustion Characteristics ◽  
Aviation Fuel ◽  
Jet Fuels ◽  
Fuel Blend ◽  
Auto Ignition ◽  
Alternative Aviation Fuels ◽  
Pressure Trace

Ignition delay of category A and C alternative aviation fuels have been investigated using a rapid compression machine (RCM). Newly introduced alternative jet fuels are not yet comprehensively understood in their combustion characteristics. Two of the category C fuels that will be primarily investigated in this study are Amyris Farnesane and Gevo Jet Fuel Blend. Amyris direct sugar to hydrocarbon (DSHC) fuel (POSF 10370) come from direct fermentation of bio feedstock sugar. Amyris DSHC is mainly composed of 2,6,10-trymethly dodecane, or farnesane. Gevo jet blend stock fuel is alcohol to jet (ATJ) fuel (POSF 10262) produced from bio derived butanol. Gevo jet blend stock is composed with iso-dodecane and iso-cetane, and has significantly low derived cetane number of 15. The experimental results are compared to combustion characteristics of conventional jet A fuels, including JP-8. Ignition delay, the important factor of auto ignition characteristic, is evaluated from pressure trace measured from the RCM at University of Illinois, Urbana-Champaign. The measurements are made at compressed pressure 20bar, intermediate and low compressed temperature, and equivalence ratio of unity and below. Direct test chamber charge method is used due to its reliable reproducibility of results. Compared to category A fuels, different combustion characteristics has been observed from category C fuels due to their irregular chemical composition.

Modeling radiative forcing by background aerosol on the basis of measurement data

2009 ◽  
Vol 45 (4) ◽  
pp. 467-477 ◽  
Author(s):  
I. A. Gorchakova ◽  
T. A. Tarasova ◽  
M. A. Sviridenkov ◽  
P. P. Anikin ◽  
E. V. Romashova
Keyword(s):  
Radiative Forcing ◽  
Measurement Data

scholarly journals Light absorption of brown carbon aerosol in the PRD region of China

2016 ◽  
Vol 16 (3) ◽  
pp. 1433-1443 ◽  
Author(s):  
J.-F. Yuan ◽  
X.-F. Huang ◽  
L.-M. Cao ◽  
J. Cui ◽  
Q. Zhu ◽  
...  
Keyword(s):  
Biomass Burning ◽  
Light Absorption ◽  
Radiative Forcing ◽  
Measurement Data ◽  
Theoretical Assumption ◽  
Ambient Aerosols ◽  
Brown Carbon ◽  
Mass Spectrometers ◽  
Rural Environments ◽  
The Pearl River

Abstract. The strong spectral dependence of light absorption of brown carbon (BrC) aerosol is regarded to influence aerosol's radiative forcing significantly. The Absorption Angstrom Exponent (AAE) method has been widely used in previous studies to attribute light absorption of BrC at shorter wavelengths for ambient aerosols, with a theoretical assumption that the AAE of "pure" black carbon (BC) aerosol equals to 1.0. In this study, the AAE method was applied to both urban and rural environments in the Pearl River Delta (PRD) region of China, with an improvement of constraining the realistic AAE of "pure" BC through statistical analysis of on-line measurement data. A three-wavelength photo-acoustic soot spectrometer (PASS-3) and aerosol mass spectrometers (AMS) were used to explore the relationship between the measured AAE and the relative abundance of organic aerosol to BC. The regression and extrapolation analysis revealed that more realistic AAE values for "pure" BC aerosol (AAEBC) were 0.86, 0.82, and 1.02 between 405 and 781 nm, and 0.70, 0.71, and 0.86 between 532 and 781 nm, in the campaigns of urbanwinter, urbanfall, and ruralfall, respectively. Roadway tunnel experiments were conducted and the results further confirmed the representativeness of the obtained AAEBC values for the urban environment. Finally, the average light absorption contributions of BrC (± relative uncertainties) at 405 nm were quantified to be 11.7 % (±5 %), 6.3 % (±4 %), and 12.1 % (±7 %) in the campaigns of urbanwinter, urbanfall, and ruralfall, respectively, and those at 532 nm were 10.0 % (±2 %), 4.1 % (±3 %), and 5.5 % (±5 %), respectively. The relatively higher BrC absorption contribution at 405 nm in the ruralfall campaign could be reasonably attributed to the biomass burning events nearby, which was then directly supported by the biomass burning simulation experiments performed in this study. This paper indicates that the BrC contribution to total aerosol light absorption at shorter wavelengths is not negligible in the highly urbanized and industrialized PRD region.

Hydroprocessed Renewable Jet Fuel Evaluation, Performance, and Emissions in a T-63 Turbine Engine

2011 ◽  
Author(s):  
Christopher D. Klingshirn ◽  
Matthew J. DeWitt ◽  
Rich Striebich ◽  
David Anneken ◽  
Linda Shafer ◽  
...  
Keyword(s):  
Air Force ◽  
Alternative Fuels ◽  
Engine Performance ◽  
Aviation Fuel ◽  
Fuel Blend ◽  
Turbine Engine ◽  
Performance And Emission ◽  
Term Operation ◽  
Fuel Blends ◽  
Aromatic Components

Due to potential beneficial environmental impacts and increased supply availability, alternative fuels derived from renewable resources are evolving on the forefront as unconventional substitutes for fossil fuel. Focus is being given to the evaluation and certification of Hydroprocessed Renewable Jet (HRJ), a fuel produced from animal fat and/or plant oils (triglycerides) by hydroprocessing, as the next potential synthetic aviation fuel. Extensive efforts have recently been performed at the Air Force Research Laboratory (AFRL) at Wright Patterson Air Force Base (WPAFB) to evaluate the potential of two HRJ fuels produced from camelina and tallow feedstocks. These have included characterization of the fuel chemical and physical fuel characteristics, and Fit-for-Purpose properties (FFP). The present effort describes general combustion performance and emission propensity of a T63-A-700 Allison turbine engine operated on the HRJs and 50/50 (by volume) HRJ/JP-8 fuel blends relative to a specification JP-8. In addition, engine and emission testing with a blend of the tallow-derived HRJ and 16% bio-derived aromatic components was completed. Fundamental engine performance characterization allows for determination of the suitability of potential synthetic fuels while quantitation of gaseous and particulate matter emissions provides an assessment of the potential environmental impact compared to current petroleum-derived fuels. In addition, an extended 150 hour endurance test was performed using a 50/50 blend of tallow-derived HRJ with JP-8 to evaluate the long-term operation of the engine with the synthetic fuel blend. This paper discusses the laboratory testing performed to characterize HRJs and results from the basic engine operability and emissions studies of the alternative fuel blends.

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