Hybrid propulsion power system for aerial vehicles

Abstract

This disclosure generally relates to a hybrid solid-state propulsion system for aerial vehicles which includes a thermoelectric generator. The thermoelectric generator includes a first heat exchanger disposed within an exhaust duct of an unmanned aerial vehicle. The thermoelectric generator further includes a first ceramic layer disposed on the first heat exchanger and a first and second metal tab bonded to the first ceramic layer. The thermoelectric generator further includes a second metal tab bonded to a second ceramic layer. At least one N-type thermoelectric leg is disposed between the first metal tab bonded to the first ceramic layer and the metal tab bonded to the second ceramic layer. Further, at least one P-type thermoelectric leg is disposed between the second metal tab bonded to the first ceramic layer and the metal tab bonded to the second ceramic layer.

What is claimed is: 
     
         1 . A thermoelectric generator, comprising:
 a first heat exchanger disposed within an exhaust duct of an unmanned aerial vehicle;   a first ceramic layer disposed on the first heat exchanger;   a first and second metal tab bonded to the first ceramic layer;   at least one metal tab bonded to a second ceramic layer;   at least one N-type thermoelectric leg disposed between the first metal tab bonded to the first ceramic layer and the at least one metal tab bonded to the second ceramic layer; and   at least one P-type thermoelectric leg disposed between the second metal tab bonded to the first ceramic layer and the at least one metal tab bonded to the second ceramic layer.   
     
     
         2 . The thermoelectric generator of  claim 1 , further comprising a second heat exchanger disposed on the second ceramic layer and implemented with at least one of an extruded aluminum and a graphite. 
     
     
         3 . The thermoelectric generator of  claim 1 , wherein the first heat exchanger is implemented with at least one of an ultrathin carbon steel, a refractory metal, a silicon carbide, and a silicon material. 
     
     
         4 . The thermoelectric generator of  claim 1 , wherein the first ceramic layer is implemented with at least one of Aluminum Nitride, Aluminum Oxide, Silicon Nitride, Molybdenum, and Aluminum. 
     
     
         5 . The thermoelectric generator of  claim 1 , wherein the at least one N-type thermoelectric leg is implemented with at least one of skutterudite materials, lead chalcogenide systems, half-Heusler compositions, rare earth element tellurides, semiconductors, and Silicon and Phosphorus doped Silicon-Germanium systems. 
     
     
         6 . The thermoelectric generator of  claim 1 , wherein the at least one P-type thermoelectric leg is implemented with at least one of skutterudite materials, lead chalcogenide systems, half-Heusler compositions, Zintl compounds, semiconductors, and Boron doped Silicon-Germanium systems. 
     
     
         7 . The thermoelectric generator of  claim 1 , wherein the at least one N-type thermoelectric leg and the at least one P-type thermoelectric leg are created by at least one of spark plasma sintering, PVD, or CVD techniques. 
     
     
         8 . The thermoelectric generator of  claim 1 , wherein the at least one N-type thermoelectric leg and the at least one P-type thermoelectric leg are disposed in an electrically series and thermally parallel configuration. 
     
     
         9 . The thermoelectric generator of  claim 1 , wherein the first heat exchanger absorbs heat from exhaust gases in the exhaust duct. 
     
     
         10 . The thermoelectric generator of  claim 9 , wherein the heat from the first heat exchanger is absorbed by the at least one N-type thermoelectric leg and the at least one P-type thermoelectric leg. 
     
     
         11 . The thermoelectric generator of  claim 10 , wherein a temperature differential is created between the at least one N-type thermoelectric leg and the at least one P-type thermoelectric leg. 
     
     
         12 . The thermoelectric generator of  claim 11 , wherein the temperature differential created between the at least one N-type thermoelectric leg and the at least one P-type thermoelectric leg creates a voltage differential between a first terminal and a second terminal. 
     
     
         13 . The thermoelectric generator of  claim 12 , wherein the voltage differential between the first terminal and the second terminal provides an electrical current to one or more electrical motors within the unmanned aerial vehicle. 
     
     
         14 . The thermoelectric generator of  claim 12 , wherein excess heat is dissipated by the second heat exchanger. 
     
     
         15 . An unmanned aerial vehicle, comprising
 a thermoelectric generator comprising:
 a first heat exchanger disposed within an exhaust duct of the unmanned aerial vehicle; 
 a first ceramic layer disposed on the first heat exchanger; 
 a first and second metal tab bonded to the first ceramic layer; 
 at least one metal tab bonded to a second ceramic layer; 
 at least one N-type thermoelectric leg disposed between the first metal tab bonded to the first ceramic layer and the at least one metal tab bonded to the second ceramic layer; and 
 at least one P-type thermoelectric leg disposed between the second metal tab bonded to the first ceramic layer and the at least one metal tab bonded to the second ceramic layer. 
   
     
     
         16 . The unmanned aerial vehicle of  claim 15 , wherein the first heat exchanger absorbs heat from exhaust gases in the exhaust duct. 
     
     
         17 . The unmanned aerial vehicle of  claim 16 , wherein the heat from the first heat exchanger is absorbed by the at least one N-type thermoelectric leg and the at least one P-type thermoelectric leg. 
     
     
         18 . The unmanned aerial vehicle of  claim 17 , wherein a temperature differential is created between the at least one N-type thermoelectric leg and the at least one P-type thermoelectric leg. 
     
     
         19 . The unmanned aerial vehicle of  claim 18 , wherein the temperature differential created between the at least one N-type thermoelectric leg and the at least one P-type thermoelectric leg creates a voltage differential between a first terminal and a second terminal. 
     
     
         20 . The unmanned aerial vehicle of  claim 19 , wherein the voltage differential between the first terminal and the second terminal provides an electrical current to one or more electrical motors within the unmanned aerial vehicle.