Abstract: Lubricant compositions comprising an oil of lubricating viscosity and a viscosity modifier that is a hydrocarbon polymer having a number average molecular weight (Mn) of less than 10,000 Daltons (Da). The viscosity modifier is present at greater than 2 wt %, based on a total weight of the lubricant composition. Exemplary hydrocarbon polymers include, but are not limited to, olefin polymers, such as polyisobutylene polybutene, ethylene ?-olefin copolymers, or combinations thereof.

Abstract: A system includes a water injection system configured to supply water from a pressure regulating valve to a water manifold of a turbine engine. The system also includes a drain valve configured to drain at least a portion of the water from the pressure regulating valve during a start-up period of the water injection system at least until a stable water pressure is achieved downstream of the pressure regulating valve.

Abstract: In one embodiment, a system includes a water injection system configured to supply water from a pressure regulating valve to a water manifold of a turbine engine. The system also includes a drain valve configured to drain at least a portion of the water from the pressure regulating valve during a start-up period of the water injection system at least until a stable water pressure is achieved downstream of the pressure regulating valve.

Abstract: A method of operating a fuel system is provided. The method includes removing fuel from at least a portion of the fuel system using a gravity drain process The method also includes channeling nitrogen into at least a portion of the fuel system to facilitate removing air and residual fuel from at least a portion of the fuel system, thereby mitigating a formation of carbonaceous precipitate particulates. The method further includes removing air and nitrogen from at least a portion of the fuel system during a fuel refilling process using a venting process, such that at least a portion of the fuel system is substantially refilled with fuel and substantially evacuated of air and nitrogen. The method also includes removing air from at least a portion of the refilled fuel system using a venting process.

Abstract: A method of operating a fuel system is provided. The method includes removing fuel from at least a portion of the fuel system using a gravity drain process. The method also includes channeling nitrogen into at least a portion of the fuel system to facilitate removing air and residual fuel from at least a portion of the fuel system, thereby mitigating a formation of carbonaceous precipitate particulates. The method further includes removing air and nitrogen from at least a portion of the fuel system during a fuel refilling process using a venting process such that at least a portion of the fuel system is substantially refilled with fuel and substantially evacuated of air and nitrogen. The method also includes removing air from at least a portion of the refilled fuel system using a venting process. The method further includes recirculating fuel within at least a portion of the fuel system, thereby removing heat from at least a portion of the fuel system and facilitating a transfer of operating fuel modes.

Abstract: A method of operating a gas turbine engine is provided. The method includes introducing a fuel into a combustor, detecting a failure of ignition of the fuel, and preventing ignition until the introduced fuel is substantially removed from the gas turbine engine.