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: Provided herein are systems and methods for separation of particulate from water using ultrasonically generated acoustic standing waves.

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: Acoustophoretic devices for separating particles from a non-flowing host fluid are disclosed. The devices include a substantially acoustically transparent container and a separation unit, with the container being placed within the separation unit. An ultrasonic transducer in the separation unit creates a planar or multi-dimensional acoustic standing wave within the container, trapping particles disposed within the non-flowing fluid and causing them to coalesce or agglomerate, then separate due to buoyancy or gravity forces.

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: Several prototype systems are described for separating oil and water from emulsions. The systems operate at ultrasonic resonance and are thus low power. Each system contains one or more acoustic transducers operating in the 100 kHz to 5 MHz range. Each system contains flow input for the emulsion and two or more flow outputs for the separated oil and water. Existing prototypes operate from 200 mL/min to >15 L/min. Each uses low power in the range of 1-5 W.

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: An apparatus for separating particles from a fluid stream includes a flow chamber that has at least one inlet and at least one outlet. At least one ultrasonic transducer is located on a wall of the flow chamber. The transducer includes a piezoelectric array with at least two piezoelectric elements. The piezoelectric array includes a piezoelectric material to create a multi-dimensional acoustic standing wave in the flow chamber. A reflector is located on the wall on the opposite side of the flow chamber from the at least one ultrasonic transducer.

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: An apparatus includes a flow chamber having at least one inlet and at least one outlet. At least one ultrasonic transducer is located on a wall of the flow chamber, which operates to create a multi-dimensional acoustic standing wave in the flow chamber. A reflector is located on the wall on the opposite side of the flow chamber from the at least one ultrasonic transducer. The reflector is formed from a thin structure that provides a pressure release boundary, such as a plastic film/air interface.

Abstract: An acoustophoresis device includes an acoustic chamber with a piezoelectric element located within its volume. The piezoelectric element vibrates and generates acoustic standing waves from both sides, so that particles can be separated from fluid passing through the acoustic chamber. This permits the element to be cooled more efficiently, reducing transient heat loads in the fluid traveling through the device.

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: Disclosed herein are systems and methods for desalination of salt water based on an engineered acoustic field that causes constructive and destructive interference at precomputed spatial positions. The engineered acoustic field can cause high-pressure and low-pressure regions where desalination membranes are located. The induced pressure from the acoustic field can force pure water through the membranes leaving ionic and dissolved molecular species behind.

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: Systems are provided with varying flow chamber configurations which acoustically agglomerate microorganisms such as algae for separation from a host fluid such as water. Related apparatus, systems, techniques and articles are also described.