Abstract: Acoustic perfusion devices for separating biological cells from other material in a fluid mixture are disclosed. The devices include an inlet port, an outlet port, and a collection port that are connected to an acoustic chamber. An ultrasonic transducer creates an acoustic standing wave in the acoustic chamber that permits a continuous flow of fluid to be recovered through the collection port while keeping the biological cells within the acoustic chamber to be returned to the bioreactor from which the fluid mixture is being drawn.

Abstract: Acoustic perfusion devices for separating biological cells from other material in a fluid mixture are disclosed. The devices include an inlet port, an outlet port, and a collection port that are connected to an acoustic chamber. An ultrasonic transducer creates an acoustic standing wave in the acoustic chamber that permits a continuous flow of fluid to be recovered through the collection port while keeping the biological cells within the acoustic chamber to be returned to the bioreactor from which the fluid mixture is being drawn.

Abstract: A perfusion bioreactor includes at least one ultrasonic transducer that can acoustically generate a multi-dimensional standing wave. The standing wave can be used to retain cells in the bioreactor, and can also be utilized to dewater or further harvest product from the waste materials produced in a bioreactor.

Abstract: An acoustic standing wave is utilized to separate components from a multi-component fluid, such as oil from an oil-water mixture, in a fluid flow scheme with an acoustophoresis device. For example, the flow scheme and device allows for trapping of the oil as the oil coalesces, agglomerates, and becomes more buoyant than the water.

Abstract: An acoustic standing wave is utilized to separate components from a multi-component fluid, such as oil from an oil-water mixture, in a fluid flow scheme with an acoustophoresis device. For example, the flow scheme and device allows for trapping of the oil as the oil coalesces, agglomerates, and becomes more buoyant than the water.

Abstract: Acoustic perfusion devices for separating biological cells from other material in a fluid medium are disclosed. The devices include an inlet port, an outlet port, and a collection port that are connected to an acoustic chamber. An ultrasonic transducer creates an acoustic standing wave in the acoustic chamber that permits a continuous flow of fluid to be recovered through the collection port while keeping the biological cells within the acoustic chamber to be returned to the bioreactor from which the fluid medium is being drawn.

Abstract: An acoustic standing wave is utilized to separate components from a multi-component fluid, such as oil from an oil-water mixture, in a fluid flow scheme with an acoustophoresis device. For example, the flow scheme and device allows for trapping of the oil as the oil coalesces, agglomerates, and becomes more buoyant than the water.

Abstract: An acoustophoresis device which includes a substantially vertical flow path of the fluid mixture in order to improve separation of particles/secondary fluid from a primary fluid is disclosed. The vertical flow path reduces velocity non-uniformities in the acoustic chamber resulting from gravity forces. The device includes an acoustic chamber in which multidimensional acoustic standing waves are generated. The fluid can be introduced into the acoustic chamber using a dump diffuser in which a plurality of inlets enter near the bottom of the acoustic chamber such that flow symmetry reduces both, gravity driven flow non-uniformities, and any flow interference effects between inlet mixture flow into the acoustic chamber and the continuous gravity driven particle cluster drop out.

Abstract: A system having improved trapping force for acoustophoresis is described where the trapping force is improved by manipulation of the frequency of the ultrasonic transducer. The transducer includes a ceramic crystal. The crystal may be directly exposed to fluid flow. The crystal may be air backed, resulting in a higher Q factor.

Abstract: The present disclosure includes a shrouded fluid turbine that generates large wake expansion to generate power coefficients greater than the Betz power coefficient of 16/27 based on maximum system area. The Virtual Diffuser Wind Turbine (VDWT) system operates differently with, and without power extraction. With power extraction the VDWT system includes a high rotor thrust coefficient combined with an annular shroud system that uses bypass flow to form an annular, high-energy bypass flow stream that flows outward at the exit plane of the VDWT generating an observable virtual diffuser downstream therefrom. This outward, high-energy flow reduces exit plane pressure generating large wake expansions. The large wake expansion increases the flow rate through the rotor. Without rotor power extraction, separation takes place which reduces some of aerodynamic loads on the VDWT at extreme winds.

Abstract: An acoustic standing wave is utilized to separate components from a multi-component fluid, such as oil from an oil-water mixture, in a fluid flow scheme with an acoustophoresis device. For example, the flow scheme and device allows for trapping of the oil as the oil coalesces, agglomerates, and becomes more buoyant than the water.

Abstract: A disposable bioreactor system includes a bag having a first end and a second end. An acoustophoresis device is disposed at the first end of the bag, and is separable from the bag. An actuating mechanism is operably connected to the second end of the bag. The actuating mechanism is configured to move the second end of the bag towards the acoustophoresis device, so that fluids within the volume of the bag flow past the acoustophoresis device and carry desired biomolecules out of the bag for collection, while cells and other debris remain within the bag for disposal.

Abstract: A system having improved trapping force for acoustophoresis is described where the trapping force is improved by manipulation of the frequency of the ultrasonic transducer. The transducer includes a ceramic crystal. The crystal may be directly exposed to fluid flow. The crystal may be air backed, resulting in a higher Q factor.

Abstract: An acoustophoresis device made up of modular components is disclosed. Several modules are disclosed herein, including ultrasonic transducer modules, input/output modules, collection well modules, and various connector modules. These permit different systems to be constructed that have appropriate fluid dynamics for separation of particles, such as biological cells, from a fluid.

Abstract: An acoustic standing wave is utilized to separate components from a multi-component fluid, such as animal cells from fluid-cell mixture, in a fluid flow scheme with an acoustophoresis device. For example, the flow scheme and device allows for trapping of falling cells as the cells coalesce, agglomerate, and the weight of the agglomerated mass overcomes the drag and ultrasonic standing wave forces in the device.

Abstract: A fluid turbine comprises a turbine shroud and an optional ejector shroud. The turbine shroud and/or the ejector shroud are formed from a hard shell and a membrane. The hard shell forms a leading edge, a trailing edge, and an interior surface of the shroud. The membrane forms an exterior surface of the shroud. The resulting construction is lighter than previous turbine shrouds.

Abstract: A perfusion bioreactor includes at least one ultrasonic transducer that can acoustically generate a multi-dimensional standing wave. The standing wave can be used to retain cells in the bioreactor, and can also be utilized to dewater or further harvest product from the waste materials produced in a bioreactor.

Abstract: A shrouded fluid turbine comprises an impeller and a turbine shroud surrounding the impeller. The inlet of the turbine shroud is flared. The shroud includes alternating inward and outward curving lobe segments along a trailing edge of the turbine shroud. The inward and outward curving lobe segments have exposed lateral surfaces, or in other words do not have sidewalls joining the inward and outward curving lobe segments. This allows for both transverse mixing and radial mixing of air flow through the turbine shroud with air flow passing along the exterior of the turbine shroud.

Abstract: A shrouded wind turbine comprises a shroud disposed about an impeller. The impeller surrounds a nacelle body which is shaped to enhance smooth flow of wind through the impeller. Some embodiments include an inlet and an outlet in the nacelle body, allowing airflow through an interior cavity. Other nacelle bodies may be tapered, flared, include mixing lobes around a trailing edge, or may have other shapes that enhance fluid flow. Some nacelle bodies include an annular groove that promotes flow attachment. Maintaining airflow attachment to the nacelle body within the turbine increases the energy generation capacity of the wind turbine.