Methods and apparatus for operating an internal combustion engine

Abstract

A piston assembly for an internal combustion engine is provided. The piston assembly includes at least one connecting rod comprising at least one wall that defines at least one first cooling fluid passage within the connecting rod. The piston assembly also includes at least one piston body including at least one wall coupled to the connecting rod. The piston body wall defines at least one second cooling fluid passage within the piston body that is coupled in flow communication with the first cooling fluid passage. The piston assembly further includes at least one piston pin positioned within the second cooling fluid passage and is coupled to at least a portion of the connecting rod and at least a portion of the piston body. The piston assembly also includes at least one piston crown including at least one wall coupled to the piston body. The piston crown wall defines at least one third cooling fluid passage within the piston crown. The third cooling fluid passage is coupled in flow communication with the second cooling fluid passage.

1 . A piston assembly for an internal combustion engine comprising:
 at least one connecting rod comprising at least one wall, said connecting rod wall defining at least one first cooling fluid passage within said connecting rod;   at least one piston body comprising at least one wall coupled to said at least one connecting rod, said piston body wall defining at least one second cooling fluid passage within said piston body, said second cooling fluid passage coupled in flow communication with said first cooling fluid passage;   at least one piston pin positioned within said second cooling fluid passage and coupled to at least a portion of said connecting rod and at least a portion of said piston body; and   at least one piston crown comprising at least one wall coupled to said piston body, said piston crown wall defining at least one third cooling fluid passage within said piston crown, said third cooling fluid passage coupled in flow communication with said second cooling fluid passage.   
   
   
       2 . A piston assembly in accordance  claim 1  wherein said second cooling fluid passage comprises a cross-passage, said cross-passage facilitating channeling a cooling fluid from said connecting rod to said piston body. 
   
   
       3 . A piston assembly in accordance  claim 1  wherein said piston pin comprises at least one sealing plug positioned within said second cooling fluid passage. 
   
   
       4 . A piston assembly in accordance  claim 3  wherein said sealing plug is substantially cylindrical and extends between and is coupled to a plurality of axially opposing piston body segments, said sealing plug facilitating channeling a cooling fluid from said connecting rod to said piston crown. 
   
   
       5 . A piston assembly in accordance  claim 1  wherein said piston pin comprises at least one piston pin wall, said piston pin wall facilitating channeling a cooling fluid from said a connecting rod to said piston crown. 
   
   
       6 . A piston assembly in accordance  claim 1  wherein at least a portion of said piston crown and at least a portion of said piston body define at least one fourth cooling fluid passage therebetween, said fourth cooling fluid passage coupled in flow communication with said third cooling fluid passage and facilitating compression ignition. 
   
   
       7 . A method of operating an internal combustion engine comprising channeling at least one cooling fluid to a piston crown of a piston assembly thereby facilitating compression ignition. 
   
   
       8 . A method of operating an internal combustion engine in accordance with  claim 7  wherein said channeling at least one cooling fluid to a piston crown comprises channeling the fluid such that a radially outer portion of the piston crown has a first temperature and a radially inner portion of the piston crown has a second temperature, the second temperature is greater than the first temperature. 
   
   
       9 . A method of operating an internal combustion engine in accordance with  claim 8  wherein said channeling the fluid comprises providing at least one fluid passage dimensioned to facilitate at plurality of predetermined rates of heat transfer such that a radially outer portion of the piston crown has a first predetermined rate of heat transfer and a radially inner portion of the piston crown has a second predetermined rate of heat transfer, the first predetermined rate of heat transfer is greater than the second predetermined rate of heat transfer. 
   
   
       10 . An internal combustion engine comprising:
 at least one substantially cylindrical housing; and   a plurality of opposed piston assemblies enclosed within said at least one cylindrical housing, said plurality of opposed piston assemblies comprising at least one connecting rod, at least one piston body, at least one piston pin, and at least one piston crown, said connecting rod comprising at least one wall, said wall defining at least one first cooling fluid passage within said connecting rod, said piston body comprising at least one wall coupled to said connecting rod, said piston body wall defining at least one second cooling fluid passage within said piston body, said second cooling fluid passage coupled in flow communication with said first cooling fluid passage, said piston pin positioned within said second cooling fluid passage and coupled to at least a portion of said connecting rod and at least a portion of said piston body, said piston crown comprising at least one wall coupled to said piston body, said piston crown wall defining at least one third cooling fluid passage within said piston crown, said third cooling fluid passage coupled in flow communication with said second cooling fluid passage.   
   
   
       11 . An engine in accordance  claim 10  wherein said second cooling fluid passage comprises a cross-passage, said cross-passage facilitating channeling a cooling fluid from said connecting rod to said piston body. 
   
   
       12 . An engine in accordance  claim 10  wherein said piston pin comprises at least one sealing plug positioned within said second cooling fluid passage. 
   
   
       13 . An engine in accordance  claim 12  wherein said sealing plug is substantially cylindrical and extends between and is coupled to a plurality of axially opposing piston body segments, said sealing plug facilitating channeling a cooling fluid from said connecting rod to said piston crown. 
   
   
       14 . An engine in accordance  claim 10  wherein said piston pin comprises piston pin wall, said piston pin wall facilitating channeling a cooling fluid from said connecting rod to said piston crown. 
   
   
       15 . An engine in accordance  claim 10  wherein at least a portion of said piston crown and at least a portion of said piston body define at least one fourth cooling fluid passage therebetween, said fourth cooling fluid passage coupled in flow communication with said third cooling fluid passage and facilitating compression ignition.