Abstract
The formation of contrails (condensation trails) from aircraft exhaust has been investigated since 1919. Related studies are reviewed. The thermodynamical foundation of the Appleman threshold criterion for contrail formation has been first described by SCHMIDT in 1940. The Schmidt/Appleman criterion is reexamined, including the effects of the conversion of part of the combustion heat into kinetic energy of the motions in the wake of the aircraft causing higher threshold temperatures for contrail formation than without this conversion. The criterion is also derived including the kinetic energy of the jet plumes but this effect changes the threshold temperature only a little. The analysis is applied for a measured test case with the so-called ATTAS aircraft and for typical modern wide-body aircraft of type B747. If the aircraft would burn liquid hydrogen (liquid methane) instead of kerosene fuel, contrails would appear at typically 10 K (4.5 K) higher ambient temperatures and would be geometrically thicker and longer. However, this does not necessarily mean that such alternative fuels have a stronger impact on climate because such fuels will cause less and larger particles with smaller optical thickness and faster sedimentation. (orig.)
Schumann, U
[1]
- Deutsche Forschungsanstalt fuer Luft- und Raumfahrt, Oberpfaffenhofen (Germany). Inst. fuer Phys.
Citation Formats
Schumann, U.
On conditions for contrail formation from aircraft exhausts.
Germany: N. p.,
1996.
Web.
Schumann, U.
On conditions for contrail formation from aircraft exhausts.
Germany.
Schumann, U.
1996.
"On conditions for contrail formation from aircraft exhausts."
Germany.
@misc{etde_233640,
title = {On conditions for contrail formation from aircraft exhausts}
author = {Schumann, U}
abstractNote = {The formation of contrails (condensation trails) from aircraft exhaust has been investigated since 1919. Related studies are reviewed. The thermodynamical foundation of the Appleman threshold criterion for contrail formation has been first described by SCHMIDT in 1940. The Schmidt/Appleman criterion is reexamined, including the effects of the conversion of part of the combustion heat into kinetic energy of the motions in the wake of the aircraft causing higher threshold temperatures for contrail formation than without this conversion. The criterion is also derived including the kinetic energy of the jet plumes but this effect changes the threshold temperature only a little. The analysis is applied for a measured test case with the so-called ATTAS aircraft and for typical modern wide-body aircraft of type B747. If the aircraft would burn liquid hydrogen (liquid methane) instead of kerosene fuel, contrails would appear at typically 10 K (4.5 K) higher ambient temperatures and would be geometrically thicker and longer. However, this does not necessarily mean that such alternative fuels have a stronger impact on climate because such fuels will cause less and larger particles with smaller optical thickness and faster sedimentation. (orig.)}
journal = []
issue = {1}
volume = {5}
journal type = {AC}
place = {Germany}
year = {1996}
month = {Jun}
}
title = {On conditions for contrail formation from aircraft exhausts}
author = {Schumann, U}
abstractNote = {The formation of contrails (condensation trails) from aircraft exhaust has been investigated since 1919. Related studies are reviewed. The thermodynamical foundation of the Appleman threshold criterion for contrail formation has been first described by SCHMIDT in 1940. The Schmidt/Appleman criterion is reexamined, including the effects of the conversion of part of the combustion heat into kinetic energy of the motions in the wake of the aircraft causing higher threshold temperatures for contrail formation than without this conversion. The criterion is also derived including the kinetic energy of the jet plumes but this effect changes the threshold temperature only a little. The analysis is applied for a measured test case with the so-called ATTAS aircraft and for typical modern wide-body aircraft of type B747. If the aircraft would burn liquid hydrogen (liquid methane) instead of kerosene fuel, contrails would appear at typically 10 K (4.5 K) higher ambient temperatures and would be geometrically thicker and longer. However, this does not necessarily mean that such alternative fuels have a stronger impact on climate because such fuels will cause less and larger particles with smaller optical thickness and faster sedimentation. (orig.)}
journal = []
issue = {1}
volume = {5}
journal type = {AC}
place = {Germany}
year = {1996}
month = {Jun}
}