Turbine rotor blade platform cooling

A combustion turbine engine comprising:

• a compressor;
• a combustor;
• a turbine;
• and
• a turbine rotor blade having a platform cooling arrangement;
• wherein the turbine rotor blade includes a platform at an interface between an airfoil and a root, wherein the rotor blade includes an interior cooling passage formed therein that extends from a connection with a coolant source at the root to the approximate radial height of the platform, wherein, in operation, the interior cooling passage comprises a high-pressure coolant region and a low-pressure coolant region, and wherein along a side that coincides with a suction side of the airfoil, a suction side of the platform comprises a topside extending circumferentially from the airfoil to a suction side slashface, and wherein the suction side of the platform comprises an aft edge that coincides with a trailing edge of the airfoil, the platform cooling arrangement including:
• a manifold positioned within an aft side of the suction side of the platform;
• a high-pressure connector that connects the manifold to the high-pressure coolant region of the interior cooling passage;
• a low-pressure connector that connects the manifold to the low-pressure coolant region of the interior cooling passage;
• and
• heat transfer structure positioned within the manifold to interact with a coolant flowing from the high-pressure connector to the low-pressure connector during operation.