Turbocharger, system, and method for draining fluid from a turbocharger

Abstract

Various methods and systems are provided for removing fluid from a turbocharger turbine. In one example, a turbocharger comprises a turbine including a casing housing a rotor, a drain passage coupled to the casing, and an air jet coupled to the drain passage, the air jet supplying intake air from a high-pressure compressor outlet to the drain passage.

1 . A turbocharger, comprising:
 a turbine including a casing housing a rotor;   a drain passage coupled to the casing; and   an air jet coupled to the drain passage, the air jet configured to supply intake air from a high-pressure compressor outlet to the drain passage.   
     
     
         2 . The turbocharger of  claim 1 , wherein the turbine is a low-pressure turbine located downstream of a high-pressure turbine in an exhaust flow path. 
     
     
         3 . The turbocharger of  claim 1 , wherein the turbine is mechanically coupled to a low-pressure compressor located upstream of the high-pressure compressor in an intake air flow path. 
     
     
         4 . The turbocharger of  claim 1 , wherein the turbine casing is open to atmosphere in at least one location. 
     
     
         5 . The turbocharger of  claim 1 , wherein the drain passage is coupled to atmosphere. 
     
     
         6 . The turbocharger of  claim 1 , wherein the drain passage is coupled to a vertical low point of the casing. 
     
     
         7 . The turbocharger of  claim 1 , wherein the turbine is located downstream of an engine, and wherein the drain passage is configured to passively drain fluid from the casing when the engine is not operating. 
     
     
         8 . The turbocharger of  claim 7 , wherein the drain passage is configured to seal a flow of exhaust gas from the casing to atmosphere when the engine is operating. 
     
     
         9 . The turbocharger of  claim 1 , wherein the turbocharger is installed in a vehicle, and wherein a pressure of the intake air from the high-pressure compressor outlet is greater than atmospheric pressure during engine operation. 
     
     
         10 . A system, comprising:
 an engine;   a first turbocharger including a first turbine mechanically coupled to a first compressor;   a second turbocharger including a second turbine located downstream of the first turbine in an exhaust flow path, the second turbine mechanically coupled to a second compressor, the second compressor located upstream of the first compressor in an intake flow path;   a drain passage coupling the second turbine to atmosphere; and   a compressed air line coupling the drain passage to an outlet of the first compressor.   
     
     
         11 . The system of  claim 10 , wherein the drain passage is configured to passively drain fluid from the second turbine when the engine is not operating. 
     
     
         12 . The system of  claim 10 , wherein the drain passage is configured to seal a flow of exhaust gas from the second turbine to atmosphere when the engine is operating. 
     
     
         13 . The system of  claim 12 , wherein, when the engine is operating, compressed intake air flows from the outlet of the first compressor to the drain passage through the compressed air line in order to seal the flow of exhaust gas. 
     
     
         14 . A vehicle comprising:
 a vehicle platform; and   the system of  claim 10  attached to the vehicle platform.   
     
     
         15 . A method, comprising:
 when a pressure of intake air at a high-pressure compressor outlet is greater than a pressure of exhaust gas downstream of a low-pressure turbine, sealing a flow of exhaust gas from the low-pressure turbine through a drain passage to atmosphere; and   when the pressure of intake air at the high-pressure compressor outlet is not greater than the pressure of exhaust gas downstream of the low-pressure turbine, draining fluid from the low-pressure turbine through the drain passage.   
     
     
         16 . The method of  claim 15 , wherein sealing the flow of exhaust gas from the low-pressure turbine through the drain passage to atmosphere further comprises directing air from the high-pressure compressor outlet to the drain passage. 
     
     
         17 . The method of  claim 15 , wherein the pressure of intake air at the high-pressure compressor outlet being greater than the pressure of exhaust gas downstream of the low-pressure turbine occurs during engine operation. 
     
     
         18 . The method of  claim 15 , wherein the pressure of intake air at the high-pressure compressor outlet being no greater than the pressure of exhaust gas downstream of the low-pressure turbine occurs during engine off conditions. 
     
     
         19 . The method of  claim 15 , further comprising compressing the intake air with the high-pressure compressor, the high-pressure compressor driven by a high-pressure turbine. 
     
     
         20 . The method of  claim 15 , further comprising compressing the intake air with the high-pressure compressor, the high-pressure compressor driven by at least one of a motor or an engine.