Abstract: A device for generating a pulsed flow in a channel containing a circulating algal culture can include a plate that is pivotably mounted on the channel and an activator. A pulsed flow is generated in the channel by first positioning the plate to impede the flow of circulating algal culture and then rotating the plate to a submerged position. The pulsed flow can be employed to counteract the negative effects of bio-fouling on algae cultivation equipment. In another arrangement, a device for generating a pulsed flow in a sloped raceway that is in fluid communication with a sump can include a gate. In different embodiments, the gate can operate as a so-called “pinch gate” or as a so-called “overflow gate.” In another aspect, a variable rate pump, such as a centrifugal pump, a screw pump or an airlift pump, is described for establishing a pulsed flow in a channel.

Abstract: Cooling air is provided from a source of cooling air through a cooling air circuit in a turbine section of a gas turbine engine. A first portion of cooling air is provided from the source along a first path of the circuit to a plurality of blades associated with a stage of the turbine section. A second portion of cooling air is provided from the source along a second path of the circuit. The second path includes a turbine disc bore where the cooling air provides cooling to a radially innermost portion of at least one turbine disc that forms a part of a rotor of the engine. The second path is independent from the first path such that the second portion of cooling air bypasses the stage and is not mixed with the first portion of cooling air in the circuit after leaving the source.

Abstract: A turbine engine including an intermediate space defined between outer and inner portions of the turbine engine. A flow energizer is provided including a flow body located within the intermediate space and including an inlet port, an outlet port and a flow passage extending within the flow body between the inlet and outlet ports. The inlet port receives a flow of a first medium located within the intermediate space and the flow body injects an energizing flow of a second medium to a portion of the first medium within the flow body to create an energized flow of a mixed medium from the outlet portion, the energized flow of mixed medium creates a flow of the first medium adjacent to the flow body within the intermediate space.

Abstract: A power turbine receiving cooling fluid from compressor apparatus is provided. The turbine comprises: fixed housing structure; a support shaft rotatably supported in the housing structure; at least one disk overhung on the support shaft and coupled to the support shaft so as to rotate with the support shaft; and cooling fluid structure. The at least one disk is formed from a low-alloy-content steel. The cooling fluid supply structure extends through the support shaft and the at least one disk so as to supply cooling fluid to the at least one disk.

Abstract: A shell air recirculation system for use in a gas turbine engine includes one or more outlet ports located at a bottom wall section of an engine casing wall and one or more inlet ports located at a top wall section of the engine casing wall. The system further includes a piping system that provides fluid communication between the outlet port(s) and the inlet port(s), a blower for extracting air from a combustor shell through the outlet port(s) and for conveying the extracted air to the inlet port(s), and a valve system for selectively allowing and preventing air from passing through the piping system. The system operates during less than full load operation of the engine to circulate air within the combustor shell but is not operational during full load operation of the engine.

Abstract: A device for generating a pulsed flow in a channel containing a circulating algal culture can include a plate that is pivotably mounted on the channel and an activator. A pulsed flow is generated in the channel by first positioning the plate to impede the flow of circulating algal culture and then rotating the plate to a submerged position. The pulsed flow can be employed to counteract the negative effects of bio-fouling on algae cultivation equipment. In another arrangement, a device for generating a pulsed flow in a sloped raceway that is in fluid communication with a sump can include a gate. In different embodiments, the gate can operate as a so-called “pinch gate” or as a so-called “overflow gate.” In another aspect, a variable rate pump, such as a centrifugal pump, a screw pump or an airlift pump, is described for establishing a pulsed flow in a channel.

Abstract: A turbine engine shutdown temperature control system configured to foster consistent air temperature within cavities surrounding compressor and turbine blade assemblies to eliminate turbine and compressor blade tip rub during warm restarts of gas turbine engines is disclosed. The turbine engine shutdown temperature control system may include one or more air amplifiers positioned in a turbine case. An exhaust outlet of the air amplifier may extend into a cavity created by a turbine case and may be configured to exhaust air in a generally circumferential direction to entrain air within the cavity to flow circumferentially to establish a consistent air temperature within the cavity thereby preventing uneven cooling of turbine engine components after shutdown and prevent damage to turbine components during a warm restart.

Abstract: A turbine engine heating system configured to heat compressor and turbine blade assemblies to eliminate turbine and compressor blade tip rub during warm restarts of gas turbine engines is disclosed. The turbine engine heating system may include a heating air extraction system configured to withdraw air from the turbine engine and to pass that air thru a heating element configured to increase a temperature of the air supplied by the heating air extraction system. The air may then be passed to a heating air supply system via an air movement device. The heating air supply system may be in communication with a turbine cylinder cavity of the turbine engine positioned radially outward from at least one turbine assembly. The heated air may be passed into the turbine cylinder cavity to reduce the cooling rate of the turbine vane carriers after shutdown and before a warm restart to limit tip rubbing.

Abstract: A turbine engine shutdown temperature control system configured to limit thermal gradients from being created within an outer casing surrounding a turbine blade assembly during shutdown of a gas turbine engine is disclosed. By reducing thermal gradients caused by hot air buoyancy within the mid-region cavities in the outer casing, arched and sway-back bending of the outer casing is prevented, thereby reducing the likelihood of blade tip rub, and potential blade damage, during a warm restart of the gas turbine engine. The turbine engine shutdown temperature control system may operate during the shutdown process where the rotor is still powered by combustion gases or during turning gear system operation after shutdown of the gas turbine engine, or both, to allow the outer casing to uniformly, from top to bottom, cool down.

Abstract: During full load operation of gas turbine engine operation, a valve system is maintained in a closed position to substantially prevent air from passing through a piping system of a shell air recirculation system. Upon initiation of a turn down operation, which is implemented to transition the engine to a turning gear state or a shut down state, the valve system is opened to allow air to pass through the piping system. A blower is operated to extract air through at least one outlet port of the shell air recirculation system from an interior volume of an engine casing portion associated with the combustion section, to convey the extracted air through the piping system, and to inject the air into the interior volume of the engine casing portion through at least one inlet port of the shell air recirculation system to circulate air within the engine casing portion.

Abstract: A system and method for using a pulse flow to circulate algae in an algae cultivation apparatus are provided. In order to counteract the negative effects of biofouling on algae cultivation equipment, a pulse flow is created to periodically move through an algae cultivation apparatus. The pulse flow will dislodge algae cells adhering to various surfaces of the apparatus, and it will also create turbulence to stir up any algae cells which may have settled onto the bottom of the apparatus. To produce an increased fluid flow rate required to create an effective pulse flow, a sump, which is periodically filled with drawn algal culture from the apparatus, is located at an elevated position above the apparatus. When released, the algal culture travels through a transfer pipe and into the apparatus with gravity causing the algal culture to flow at a very high rate.

Abstract: A turbine engine including an intermediate space defined between outer and inner portions of the turbine engine. A flow energizer is provided including a flow body located within the intermediate space and including an inlet port, an outlet port and a flow passage extending within the flow body between the inlet and outlet ports. The inlet port receives a flow of a first medium located within the intermediate space and the flow body injects an energizing flow of a second medium to a portion of the first medium within the flow body to create an energized flow of a mixed medium from the outlet portion, the energized flow of mixed medium creates a flow of the first medium adjacent to the flow body within the intermediate space.

Abstract: A shell air recirculation system for use in a gas turbine engine includes one or more outlet ports located at a bottom wall section of an engine casing wall and one or more inlet ports located at a top wall section of the engine casing wall. The system further includes a piping system that provides fluid communication between the outlet port(s) and the inlet port(s), a blower for extracting air from a combustor shell through the outlet port(s) and for conveying the extracted air to the inlet port(s), and a valve system for selectively allowing and preventing air from passing through the piping system. The system operates during less than full load operation of the engine to circulate air within the combustor shell but is not operational during full load operation of the engine.

Abstract: During full load operation of gas turbine engine operation, a valve system is maintained in a closed position to substantially prevent air from passing through a piping system of a shell air recirculation system. Upon initiation of a turn down operation, which is implemented to transition the engine to a turning gear state or a shut down state, the valve system is opened to allow air to pass through the piping system. A blower is operated to extract air through at least one outlet port of the shell air recirculation system from an interior volume of an engine casing portion associated with the combustion section, to convey the extracted air through the piping system, and to inject the air into the interior volume of the engine casing portion through at least one inlet port of the shell air recirculation system to circulate air within the engine casing portion.

Abstract: Cooling air is provided from a source of cooling air through a cooling air circuit in a turbine section of a gas turbine engine. A first portion of cooling air is provided from the source along a first path of the circuit to a plurality of blades associated with a stage of the turbine section. A second portion of cooling air is provided from the source along a second path of the circuit. The second path includes a turbine disc bore where the cooling air provides cooling to a radially innermost portion of at least one turbine disc that forms a part of a rotor of the engine. The second path is independent from the first path such that the second portion of cooling air bypasses the stage and is not mixed with the first portion of cooling air in the circuit after leaving the source.

Abstract: A system and method for using a pulse flow to circulate algae in an algae cultivation apparatus are provided. In order to counteract the negative effects of biofouling on algae cultivation equipment, a pulse flow is created to periodically move through an algae cultivation apparatus. The pulse flow will dislodge algae cells adhering to various surfaces of the apparatus, and it will also create turbulence to stir up any algae cells which may have settled onto the bottom of the apparatus. To produce an increased fluid flow rate required to create an effective pulse flow, a sump, which is periodically filled with drawn algal culture from the apparatus, is located at an elevated position above the apparatus. When released, the algal culture travels through a transfer pipe and into the apparatus with gravity causing the algal culture to flow at a very high rate.

Abstract: A winding for use in a superconducting electric generator having a rotating rotor assembly surrounded by a non-rotating stator assembly is provided. The winding comprises at least one conductor structure associated with a component in the superconducting electric generator. The conductor structure comprises a plurality of conductive elements formed from a high temperature superconductive material. At least a portion of the conductive elements is arranged in a transposed relationship. A protective shell is positioned about the conductive elements and formed from a high strength alloy suitable for cryogenic temperatures.

Abstract: A system and method for using a pulse flow to circulate algae in an algae cultivation apparatus are provided. In order to counteract the negative effects of biofouling on algae cultivation equipment, a pulse flow is created to periodically move through an algae cultivation apparatus. The pulse flow will dislodge algae cells adhering to various surfaces of the apparatus, and it will also create turbulence to stir up any algae cells which may have settled onto the bottom of the apparatus. To produce an increased fluid flow rate required to create an effective pulse flow, a sump, which is periodically filled with drawn algal culture from the apparatus, is located at an elevated position above the apparatus. When released, the algal culture travels through a transfer pipe and into the apparatus with gravity causing the algal culture to flow at a very high rate.

Abstract: A system and method for using a pulse flow to circulate algae in an algae cultivation apparatus are provided. In order to counteract the negative effects of biofouling on algae cultivation equipment, a pulse flow is created to periodically move through an algae cultivation apparatus. The pulse flow will dislodge algae cells adhering to various surfaces of the apparatus, and it will also create turbulence to stir up any algae cells which may have settled onto the bottom of the apparatus. To produce an increased fluid flow rate required to create an effective pulse flow, a sump, which is periodically filled with drawn algal culture from the apparatus, is located at an elevated position above the apparatus. When released, the algal culture travels through a transfer pipe and into the apparatus with gravity causing the algal culture to flow at a very high rate.

Abstract: A power turbine receiving cooling fluid from compressor apparatus is provided. The turbine comprises: fixed housing structure; a support shaft rotatably supported in the housing structure; at least one disk overhung on the support shaft and coupled to the support shaft so as to rotate with the support shaft; and cooling fluid structure. The at least one disk is formed from a low-alloy-content steel. The cooling fluid supply structure extends through the support shaft and the at least one disk so as to supply cooling fluid to the at least one disk.