Echogen Power Systems Inc. | Date: 2016-08-08
A heat engine system and a method for cooling a fluid stream in thermal communication with the heat engine system are provided. The heat engine system may include a working fluid circuit configured to flow a working fluid therethrough, and a cooling circuit in fluid communication with the working fluid circuit and configured to flow the working fluid therethrough. The cooling circuit may include an evaporator in fluid communication with the working fluid circuit and configured to be in fluid communication with the fluid stream. The evaporator may be further configured to receive a second portion of the working fluid from the working fluid circuit and to transfer thermal energy from the fluid stream to the second portion of the working fluid.
Echogen Power Systems Inc., Giegel, Held, Bowan and Cameron Inc. | Date: 2017-05-03
A method for controlling a heat engine system, comprising: initiating flow of a working fluid through a working fluid circuit having a high pressure side and a low pressure side by controlling a pump to pressurize and circulate the working fluid through the working fluid circuit; determining a configuration of the working fluid circuit by determining which of a plurality of waste heat exchangers and which of a plurality of recuperators to position in the high pressure side of the working fluid circuit; determining, based on the determined configuration of the working fluid circuit, which of a plurality of valves to position in a closed position to isolate a portion of the working fluid from the working fluid flowing through the working fluid circuit; receiving data corresponding to a measured temperature and/or pressure of the working fluid flowing through the working fluid circuit; determining whether the measured temperature and/or pressure exceeds a predetermined threshold; and actuating, if the measured temperature and/or pressure exceeds the predetermined threshold, one or more of the plurality of valves positioned in the closed position to position the one or more of the plurality of valves in an opened position or a partially opened position to enable at least a portion of the isolated portion of the working fluid to flow through the working fluid circuit.
Echogen Power Systems Inc. | Date: 2017-04-19
A turbopump system includes a pump portion including a housing having a pressure release passageway disposed therein. The pump portion is disposed between a high pressure side and a low pressure side of a working fluid circuit. A drive turbine is coupled to the pump portion and configured to drive the pump portion to enable the pump portion to circulate a working fluid through the working fluid circuit. A pressure release valve is fluidly coupled to the pressure release passageway and configured to be positioned in an opened position to enable pressure to be released through the pressure release passageway and in a closed position to disable pressure from being released through the pressure release passageway.
Echogen Power Systems Inc. | Date: 2017-04-19
A method includes controlling a bearing fluid supply system to provide the bearing fluid to a hydrostatic bearing of the turbopump assembly. The bearing fluid includes a supercritical working fluid. The method also includes receiving data corresponding to a pressure of the bearing fluid measured at or near a bearing fluid drain fluidly coupled to the hydrostatic bearing, determining a thermodynamic state of the bearing fluid at or near the bearing fluid drain based at least in part on the received data, and controlling a backpressure regulation valve to throttle the backpressure regulation valve between an opened position and a closed position to regulate a backpressure in a bearing fluid discharge line to maintain the bearing fluid in a supercritical state in the hydrostatic bearing and/or at or near the bearing fluid drain.
Echogen Power Systems Inc. | Date: 2014-08-27
Embodiments of the invention generally provide a heat engine system, a mass management system (MMS), and a method for regulating pressure in the heat engine system while generating electricity. In one embodiment, the MMS contains a tank fluidly coupled to a pump, a turbine, a heat exchanger, an offload terminal, and a working fluid contained in the tank at a storage pressure. The working fluid may be at a system pressure proximal an outlet of the heat exchanger, at a low-side pressure proximal a pump inlet, and at a high-side pressure proximal a pump outlet. The MMS contains a controller communicably coupled to a valve between the tank and the heat exchanger outlet, a valve between the tank and the pump inlet, a valve between the tank and the pump outlet, and a valve between the tank and the offload terminal.
Echogen Power Systems Inc. | Date: 2015-05-08
A system including a seal cartridge is provided. The seal cartridge includes a housing defining a passageway that receives a driveshaft. A dry gas seal is circumferentially disposed about the passageway within the housing at a first axial location along the housing. A magnetic liquid seal is circumferentially disposed about the passageway within the housing at a second axial location along the housing. A fluid leakage cavity is formed between the dry gas seal at the first axial location and the magnetic liquid seal at the second axial location. An extraction port is disposed in the housing and enables recovery of a leaked fluid from the fluid leakage cavity.
Echogen Power Systems Inc. | Date: 2015-07-16
Aspects of the invention provided herein include heat engine systems, methods for generating electricity, and methods for starting a turbo pump. In some configurations, the heat engine system contains a start pump and a turbo pump disposed in series along a working fluid circuit and configured to circulate a working fluid within the working fluid circuit. The start pump may have a pump portion coupled to a motor-driven portion and the turbo pump may have a pump portion coupled to a drive turbine. In one configuration, the pump portion of the start pump is fluidly coupled to the working fluid circuit downstream of and in series with the pump portion of the turbo pump. In another configuration, the pump portion of the start pump is fluidly coupled to the working fluid circuit upstream of and in series with the pump portion of the turbo pump.
Echogen Power Systems Inc. | Date: 2015-07-20
Aspects of the invention disclosed herein generally provide heat engine systems and methods for generating electricity. In one configuration, a heat engine system contains a working fluid circuit having high and low pressure sides and containing a working fluid (e.g., sc-CO_(2)). The system further contains a power turbine configured to convert thermal energy to mechanical energy, a motor-generator configured to convert the mechanical energy into electricity, and a pump configured to circulate the working fluid within the working fluid circuit. The system further contains a heat exchanger configured to transfer thermal energy from a heat source stream to the working fluid, a recuperator configured to transfer thermal energy from the low pressure side to the high pressure side of the working fluid circuit, and a condenser (e.g., air- or fluid-cooled) configured to remove thermal energy from the working fluid within the low pressure side of the working fluid circuit.
Echogen Power Systems Inc. | Date: 2014-03-13
Provided herein are a heat engine system and a method for generating energy, such as transforming thermal energy into mechanical energy and/or electrical energy. The heat engine system may have a single charging pump for efficiently implementing at least two independent tasks. The charging pump may be utilized to remove working fluid (e.g., CO2) from and/or to add working fluid into a working fluid circuit during inventory control of the working fluid. The charging pump may be utilized to transfer or otherwise deliver the working fluid as a cooling agent to bearings contained within a bearing housing of a system component during a startup process. The heat engine system may also have a mass control tank utilized with the charging pump and configured to receive, store, and distribute the working fluid.
Agency: Department of Energy | Branch: | Program: SBIR | Phase: Phase I | Award Amount: 150.00K | Year: 2016
Supercritical carbon dioxide (sCO2) power cycles offer higher thermodynamic efficiency than both traditional and advanced steam Rankine cycles. One of the significant, but rarely recognized challenges of this type of cycle is the need to actively manage the fluid inventory within the primary power cycle loop to properly control the inlet pressure to the compressor/pump(s). Without inventory management, changes in operating state due to ambient temperature, source temperature, or source heat flow result in uncontrolled variation in the inlet state to the compression devices, leading to substantial performance loss, or even physical damage to the fluid impellers. Echogen has significant experience in the operational control of megawatt-class sCO2 power cycles, and has developed control algorithms with demonstrated effectiveness in control of compressor/pump inlet pressure over a wide range of operating conditions. However, the primary method for fluid addition to the main loop is transfer of lower pressure liquid CO2 into the main loop using positive displacement pumps due to the high head and relatively low flow needed for this service. Currently-available commercial pumps of this type and capacity are generally of the plunger type. While effective and efficient, the sliding seals represent an objectionable fluid leak source, and a large component of the maintenance burden of the cycle. Traditional centrifugal pumps require a large number of stages to develop the high head needed for the fluid transfer service. As a result, they have a low overall efficiency, and require a large physical footprint. Alternatively, regenerative pumps allow for a much higher head with fewer stages. However, few commercial versions of this pump style exist, and none combine the regenerative impeller with the near-zero leakage requirement for the sCO2 application. We propose the development of a purpose-designed sCO2 “transfer pump,” which satisfies the high head, low-to-moderate flow, and zero leakage requirements of the present application. The Phase I program would include the design, fabrication and test of a subscale version of this pump. The design tools and parametric relationships derived during the Phase I program would then be used in a Phase II effort to design a full-scale version of the pump for commercial service. Key Words: Supercritical CO2, power cycles, regenerative pump