Exhaust plume cooling using periodic interruption of exhaust gas flow to form ambient air entraining vortices

Patent metadata

Field	Value
Publication number	US-9541030-B2
Application number	US-201314092147-A
Country	US
Kind code	B2
Filing date	Nov 27, 2013
Priority date	Nov 27, 2013
Publication date	Jan 10, 2017
Grant date	Jan 10, 2017

Abstract

An exhaust plume cooling device for cooling an exhaust gas plume to reduce deleterious heat effects on impinged and surrounding surfaces. The device is supportable in a position downstream of an exhaust nozzle of an exhaust gas plume-producing engine and configured to periodically interrupt the flow of exhaust gases.

First claim

What is claimed is:

1. An exhaust plume cooling device for cooling an exhaust gas plume to reduce deleterious heat effects on impinged and surrounding surfaces, the device comprising:
a vent supportable in a position downstream of an exhaust nozzle of an exhaust gas plume-producing engine and across an exhaust plume zone that is occupied by an exhaust plume when the engine is running;
an actuator operably connected to the vent and configured to alternately open and close the vent; and
a vent controller configured to command the actuator to alternately open and close at a rate and duty cycle that forms exhaust gas pulses that form vortical structures that entrain currents of ambient air.

2. The exhaust plume cooling device as defined in claim 1 in which the device is configured to periodically interrupt the flow of exhaust gases at a rate of between 1 and 1000 Hz.

3. The exhaust plume cooling device as defined in claim 2 in which the device is configured to periodically interrupt the flow of exhaust gases at a rate of 50 Hz.

4. The exhaust plume cooling device as defined in claim 1 in which configured to periodically interrupt the flow of exhaust gases at a duty cycle of between 10 and 90%.

5. The exhaust plume cooling device as defined in claim 4 in which configured to periodically interrupt the flow of exhaust gases at a 50% duty cycle.

6. The exhaust plume cooling device as defined in claim 1 in which the vent comprises an array of louvers that are operably connected to the actuator, and are simultaneously actuable between respective open and closed positions in response to commands from the vent controller.

7. A method for cooling an exhaust gas plume to reduce deleterious heat effects on impinged and surrounding surfaces; the method including the steps of;
supporting a vent across an exhaust plume zone that is occupied by an exhaust plume when an engine is running; and
periodically interrupting a flow of exhaust gases by opening and closing the vent at a rate and duty cycle sufficient to cause resulting exhaust gas pulses to form vortical structures that entrain large currents of the ambient air.

8. The method of claim 7 in which the step of periodically interrupting a flow of exhaust gases includes periodically interrupting the flow of exhaust gases at a rate of between 1 and 1000 Hz.

9. The method of claim 8 in which the step of periodically interrupting a flow of exhaust gases includes periodically interrupting the flow of exhaust gases at a rate of 50 Hz.

10. The method of claim 7 in which the step of periodically interrupting a flow of exhaust gases includes periodically interrupting the flow of exhaust gases at a duty cycle of between 10 and 90%.

11. The method of claim 10 in which the step of periodically interrupting a flow of exhaust gases includes periodically interrupting the flow of exhaust gases at a 50% duty cycle.

Assignees

• Lockheed Corp

Inventors

• Baruzzini Dan J
• Domel Neal David
• Miller Daniel N

Classifications

• F02K1/46

  Nozzles having means for adding air to the jet or for augmenting the mixing region between the jet and the ambient air, e.g. for silencing (F02K1/28, F02K1/36, F02K1/38 take precedence) · CPC title

• F02K1/28

  using fluid jets to influence the jet flow · CPC title

• F05D2220/50

  for auxiliary power units (APU's) · CPC title

• B64D41/00

  Power installations for auxiliary purposes · CPC title

• F01D25/30

  Exhaust heads, chambers, or the like · CPC title