Turbine engine including an air turbine starter and a bleed air circuit
A turbine engine including an engine core, an engine drive shaft, an accessory gear box (AGB), an air turbine starter (ATS) and a bleed air circuit. The engine core has a fan section, a compressor section, a combustion section, and a turbine section in serial flow arrangement. The engine drive shaft operably couples the fan section, the compressor section and the turbine section. The AGB and the ATS are operably coupled to the engine drive shaft.
1. An assembly for a turbine engine, the turbine engine having an engine core comprising a fan section, a compressor section, a combustion section, a turbine section, and an engine drive shaft operably coupling the fan section, the compressor section and the turbine section, the assembly comprising:
an accessory gear box (AGB);
an air turbine starter (ATS) having an ATS turbine, an ATS gearbox, an ATS drive shaft operably coupling the ATS turbine and the ATS gearbox, and an ATS output shaft operably coupling the ATS gearbox to the AGB;
a bleed air turbo (BAT) including a BAT turbine, and a BAT output shaft, the BAT output shaft being operably coupled to the AGB; and
a bleed air circuit comprising:
a first bleed air passage;
a second bleed air passage fluidly coupling the first bleed air passage to an input of the BAT; and
a third bleed air passage fluidly coupled to an output of the BAT;
wherein the BAT output shaft is driven by supplying a working fluid to the BAT through the second bleed air passage, the driving of the BAT output shaft supplying a mechanical input to and at least partially driving the AGB.
2. The assembly of claim 1 , wherein the driving of the AGB through the BAT output shaft is conducted during operation of the turbine engine.
3. The assembly of claim 1 , wherein the BAT turbine is directly coupled to the AGB through the BAT output shaft.
4. The assembly of claim 1 , further comprising a pre-cooler heat exchanger (PCE) fluidly coupled to the fan section and a system external to the turbine engine.
5. The assembly engine of claim 4 , wherein:
the bleed air circuit further comprises a bypass passage fluidly coupling the first bleed air passage to the third bleed air passage while by passing the BAT; and
the third bleed air passage fluidly couples the BAT to the PCE, and the bypass passage fluidly couples the first bleed air passage to the PCE.
6. The assembly of claim 4 , wherein:
the bleed air circuit further comprises a bypass passage fluidly coupling the first bleed air passage to the third bleed air passage while bypassing the BAT; and
the third bleed air passage and the bypass passage meet at a junction upstream of the PCE.
7. The assembly of claim 4 , wherein:
the bleed air circuit further comprises a bypass passage fluidly coupling the first bleed air passage to the third bleed air passage while bypassing the BAT; and
the PCE is selectively fluidly coupled to at least one of the third bleed air passage or the bypass passage to define a fluid input to the PCE, and fluidly coupled to the system external the turbine engine to define a fluid output of the PCE.
8. The assembly of claim 7 , wherein the PCE includes a cooling fluid input and a cooling fluid output, with the cooling fluid input being fluidly coupled to at least one of the fan section or the compressor section.
9. The assembly of claim 4 , wherein the system external the turbine engine includes an environmental control system.
10. The assembly of claim 1 , wherein:
the second bleed air passage and the third bleed air passage each include a respective working fluid with a respective temperature and respective pressure; and
the temperature and the pressure of the working fluid in the second bleed air passage is greater than the temperature and the pressure of the working fluid in the third bleed air passage.
11. The assembly of claim 1 , wherein the bleed air circuit comprises a low pressure (LP) bleed air passage, and a high pressure (HP) bleed air passage, with the LP bleed air passage being fluidly coupled to a portion of the turbine engine upstream of the HP bleed air passage.
12. The assembly of claim 11 , wherein the LP bleed air passage and the HP bleed air passage are each, independently, selectively fluidly coupled to the first bleed air passage.
13. The assembly of claim 12 , wherein the compressor section includes a high pressure (HP) compressor and a low pressure (LP) compressor, the LP bleed air passage is fluidly coupled to the LP compressor and the HP bleed air passage is fluidly coupled to the HP compressor.
14. The assembly of claim 1 , wherein the bleed air circuit further comprises an auxiliary system bleed air passage fluidly coupling the first bleed air passage to an auxiliary system.
15. The assembly of claim 1 , wherein a driving of the ATS and a driving of the BAT cause the engine drive shaft to be driven through the AGB.
16. The assembly of claim 1 , wherein the bleed air circuit further comprises a bypass passage fluidly coupling the first bleed air passage to the third bleed air passage while bypassing the BAT.
17. An assembly for a turbine engine, the turbine engine having an engine core comprising a fan section, a compressor section, a combustion section, a turbine section, and an engine drive shaft operably coupling the fan section, the compressor section and the turbine section, the assembly comprising:
an accessory gear box (AGB);
an air turbine starter (ATS) having an ATS turbine, an ATS gearbox, an ATS drive shaft operably coupling the ATS turbine and the ATS gearbox, and an ATS output shaft operably coupling the ATS gearbox to the AGB;
a bleed air turbo (BAT) including a BAT turbine, and a BAT output shaft, the BAT output shaft being operably coupled to the AGB; and
a bleed air circuit comprising:
a first bleed air passage;
a second bleed air passage fluidly coupling the first bleed air passage to an input of the BAT;
a third bleed air passage fluidly coupled to an output of the BAT; and a bypass passage fluidly coupling the first bleed air passage to the third bleed air passage while bypassing the BAT; and
a controller configured to automatically selectively supply a working fluid within the second bleed air passage to at least one of the BAT or the bypass passage, the supplying of the working fluid being based on at least one of a rotational speed or torque of the engine drive shaft or a requirement of a system external the turbine engine.
18. An assembly for a turbine engine, the turbine engine having an engine core comprising a fan section, a compressor section, a combustion section, a turbine section, and an engine drive shaft operably coupling the fan section, the compressor section and the turbine section, the assembly comprising:
an accessory gear box (AGB);
an air turbine starter (ATS) having an ATS turbine, an ATS gearbox, an ATS drive shaft operably coupling the ATS turbine and the ATS gearbox, and an ATS output shaft operably coupling the ATS gearbox to the AGB;
a bleed air turbo (BAT) including a BAT turbine, and a BAT output shaft, the BAT output shaft being operably coupled to the AGB; and
a bleed air circuit comprising:
a first bleed air passage;
a second bleed air passage fluidly coupling the first bleed air passage to an input of the BAT;
a third bleed air passage fluidly coupled to an output of the BAT; a bypass passage fluidly coupling the first bleed air passage to the third bleed air passage while bypassing the BAT; and
a fourth bleed air passage fluidly coupling at least one of the third bleed air passage or the bypass passage to the ATS.
19. The assembly of claim 18 , wherein the ATS is configured to restart, during a wind down of the turbine engine and through driving of the ATS output shaft, the turbine engine.
20. The assembly of claim 19 , wherein: a working fluid within the fourth bleed air passage is supplied to the ATS during restart of the turbine engine.