Abstract: A heat recovery steam generator (“HRSG”) 40, which is closely coupled to a gas turbine, includes a flow controls structural array 10 disposed upstream of the tubes 42 of the HRSG 40. The structural array 10 is formed of a plurality of grate-like panels 18 secured to horizontal supports 24 mounted to the support structure of the HRSG 40. The structural array 10 diffuses the high velocity exhaust stream 14 exiting the gas turbine and redistributes the gas flow evenly throughout the HRSG 40. The structural array 10 reduces wear and damage of the tubes 46.

Abstract: In a nozzle and a nozzle assembly, for use in a pressure vessel, stress analysis is used to determine areas of stress concentration. The nozzle is configured to reduce these stress concentrations.

Abstract: A heat recovery steam generator that includes a first steam drum for receiving a flow of water and steam from an evaporator. The first steam drum is adapted to provide the flow of water and steam to a second steam drum. The second steam drum is in fluid communication with the first steam drum and receives the flow of water and steam from the first steam drum and separates steam from the flow of water and steam to form a separated steam. There is a steam flow outlet positioned in the second steam drum, the steam flow outlet adapted to release the separated steam from the second steam drum.

Abstract: A radial nozzle assembly for use in a pressure vessel to enable fluid flow through the vessel wall is provided. The radial nozzle assembly has a nozzle and a cup-shaped flange extending from one end of the nozzle. The nozzle has a bore disposed therethrough along its length to permit fluid flow through the wall of the pressure vessel. The flange is defined by a generally cup or dome-shaped wall having an open end. The nozzle assembly is secured to the wall of the vessel such that the nozzle is disposed in a radial orientation to the flange and possibly in a horizontal orientation.

Abstract: An evaporator for steam generation is presented. The evaporator includes a plurality of primary evaporator stages and a secondary evaporator stage. Each primary stage includes one or more primary arrays of heat transfer tubes, an outlet manifold coupled to the arrays, and a downcomer coupled to the manifold. Each of the primary arrays has an inlet for receiving a fluid and is arranged transverse to a flow of gas through the evaporator. The gas heats the fluid flowing through the arrays to form a two phase flow. The outlet manifold receives the two phase flow from the arrays and the downcomer distributes the flow as a component of a primary stage flow. One or more of the plurality of primary evaporator stages selectively form the primary stage flow from respective components of the two phase flow, and provide the primary stage flow to inlets of the secondary evaporator stage.

Abstract: A radial nozzle assembly for use in a pressure vessel to enable fluid flow through the vessel wall is provided. The radial nozzle assembly has a nozzle and a cup-shaped flange extending from one end of the nozzle. The nozzle has a bore disposed therethrough along its length to permit fluid flow through the wall of the pressure vessel. The flange is defined by a generally cup or dome-shaped wall having an open end. The nozzle assembly is secured to the wall of the vessel such that the nozzle is disposed in a radial orientation to the flange and possibly in a horizontal orientation.

Abstract: In a nozzle and a nozzle assembly, for use in a pressure vessel, stress analysis is used to determine areas of stress concentration. The nozzle is configured to reduce these stress concentrations.

Abstract: A heat recovery steam generator that includes a first steam drum for receiving a flow of water and steam from an evaporator. The first steam drum is adapted to provide the flow of water and steam to a second steam drum. The second steam drum is in fluid communication with the first steam drum and receives the flow of water and steam from the first steam drum and separates steam from the flow of water and steam to form a separated steam. There is a steam flow outlet positioned in the second steam drum, the steam flow outlet adapted to release the separated steam from the second steam drum.

Abstract: An evaporator for steam generation is presented. The evaporator includes a plurality of primary evaporator stages and a secondary evaporator stage. Each primary stage includes one or more primary arrays of heat transfer tubes, an outlet manifold coupled to the arrays, and a downcomer coupled to the manifold. Each of the primary arrays has an inlet for receiving a fluid and is arranged transverse to a flow of gas through the evaporator. The gas heats the fluid flowing through the arrays to form a two phase flow. The outlet manifold receives the two phase flow from the arrays and the downcomer distributes the flow as a component of a primary stage flow. One or more of the plurality of primary evaporator stages selectively form the primary stage flow from respective components of the two phase flow, and provide the primary stage flow to inlets of the secondary evaporator stage.

Abstract: A method of controlling stress in a boiler pressure vessel comprises limiting the diameter of a drum (10) of the boiler pressure vessel and preheating at least a portion of the wall (12) of the drum (10). Limiting the diameter of the drum (10) allows pressure in the drum (10) to be increased for a given mechanical stress. Furthermore, preheating the wall (12) of the drum (10) reduces peak thermally induced stresses in a material from which the drum (10) is fabricated.

Abstract: A heat recovery steam generator (“HRSG”) 40, which is closely coupled to a gas turbine, includes a flow controls structural array 10 disposed upstream of the tubes 42 of the HRSG 40. The structural array 10 is formed of a plurality of grate-like panels 18 secured to horizontal supports 24 mounted to the support structure of the HRSG 40. The structural array 10 diffuses the high velocity exhaust stream 14 exiting the gas turbine and redistributes the gas flow evenly throughout the HRSG 40. The structural array 10 reduces wear and damage of the tubes 46.