System and method for controlling contrail formation
A system includes an engine of an aircraft, an oil buffer tube disposed on a bottom side of the engine, a valve disposed at or near an end of the oil buffer tube, and a control device. The control device is configured to obtain data indicating at least one operational condition associated with the aircraft or the engine. The control device is also configured to, in response to determining a first operational condition, control the valve to a first position, wherein the valve in the first position directs oil buffer air to an exhaust of the engine. The control device is also configured to, in response to determining a second operational condition, control the valve to a second position, wherein the valve in the second position directs the oil buffer air away from the exhaust of the engine.
1 . A system comprising:
an engine of an aircraft having a hot exhaust nozzle to exhaust hot exhaust gas flow;
an oil buffer tube disposed on a bottom side of the engine;
a valve disposed near an end of the oil buffer tube; and
a control device configured to:
obtain data indicating at least one operational condition associated with the aircraft or the engine;
in response to determining a first operational condition, control the valve to a first position, wherein the valve in the first position directs oil buffer air to a first portion of the oil buffer tube arranged in a first direction towards the hot exhaust nozzle and a lubrication atomization zone in the hot exhaust gas flow of the engine to atomize oil in the oil buffer air and to promote contrail formation; and
in response to determining a second operational condition, control the valve to a second position, wherein the valve in the second position directs the oil buffer air to a second portion of the oil buffer tube arranged in a second direction to exhaust the oil buffer air into a surrounding airflow and away from the hot exhaust nozzle and the lubrication atomization zone of the engine to minimize contrail formation.
2 . The system of claim 1 , wherein:
the first operational condition comprises a differential pressure (DP) across an oil seal being less than a threshold pressure; and
the second operational condition comprises the DP across the oil seal being greater than the threshold pressure.
3 . The system of claim 1 , wherein:
the first operational condition comprises a time of day associated with daytime; and
the second operational condition comprises a time of day associated with nighttime.
4 . The system of claim 1 , wherein:
the first operational condition comprises a first humidity level that is below a threshold humidity level associated with contrail formation; and
the second operational condition comprises a second humidity level that is above the threshold humidity level associated with contrail formation.
5 . The system of claim 4 , wherein the second humidity level is representative of an ice-supersaturation region proximate the aircraft.
6 . The system of claim 1 , wherein the data is obtained from at least one sensor disposed within or adjacent to a housing of the engine.
7 . The system of claim 1 , wherein the data is obtained from at least one sensor located remote from the aircraft.
8 . The system of claim 1 , wherein the at least one operational condition comprises at least one of:
a pressure inside the oil buffer tube;
an ambient pressure outside the aircraft;
a pressure differential across an oil seal;
a temperature of the air outside the aircraft;
a humidity of the air outside the aircraft;
a time of day; or
an indication of sunlight.
9 . A method comprising:
obtaining data indicating at least one operational condition associated with at least one of an aircraft or an engine of the aircraft having a hot exhaust nozzle to exhaust hot exhaust gas flow;
in response to determining a first operational condition, controlling a valve to a first position, the valve disposed near an end of an oil buffer tube disposed on a bottom side of the engine, wherein the valve in the first position directs oil buffer air to a first portion of the oil buffer tube arranged in a first direction towards the hot exhaust nozzle and a lubrication atomization zone in the hot exhaust gas flow of the engine to atomize oil in the oil buffer air and to promote contrail formation; and
in response to determining a second operational condition, controlling the valve to a second position, wherein the valve in the second position directs the oil buffer air to a second portion of the oil buffer tube arranged in a second direction to exhaust the oil buffer air into a surrounding airflow and away from the hot exhaust nozzle and the lubrication atomization zone of the engine to minimize contrail formation.
10 . The method of claim 9 , wherein:
the first operational condition comprises a differential pressure (DP) across an oil seal being less than a threshold pressure; and
the second operational condition comprises the DP across the oil seal being greater than the threshold pressure.
11 . The method of claim 9 , wherein:
the first operational condition comprises a time of day associated with daytime; and
the second operational condition comprises a time of day associated with nighttime.
12 . The method of claim 9 , wherein:
the first operational condition comprises a first humidity level that is below a threshold humidity level associated with contrail formation; and
the second operational condition comprises a second humidity level that is above the threshold humidity level associated with contrail formation.
13 . The method of claim 12 , wherein the second humidity level is representative of an ice-supersaturation region proximate the aircraft.
14 . The method of claim 9 , wherein the data is obtained from at least one sensor disposed within or adjacent to a housing of the engine.
15 . The method of claim 9 , wherein the data is obtained from at least one sensor located remote from the aircraft.