Abstract: Multi-stage acoustophoretic devices for continuously separating a second fluid or a particulate from a host fluid are disclosed. Methods of operating the multi-stage acoustophoretic devices are also disclosed. The systems may include multiple acoustophoretic devices fluidly connected to one another in series, each acoustophoretic device comprising a flow chamber, an ultrasonic transducer capable of creating a multi-dimensional acoustic standing wave, and a reflector. The systems can further include pumps and flowmeters.

Abstract: Systems and methods for increasing the accuracy of a turbidity sensor are disclosed. The systems include a turbidity sensor and a flow module with a specialized flow path, with the turbidity sensor engaging with the flow module such that a measurement zone of the turbidity sensor is disposed within a flow path of the flow module and a bypass path of the flow module does not pass through the measurement zone. The methods include flowing a fluid containing bubbles into a system that separates the fluid in the flow module into a first stream of fluid containing relatively more bubbles and a second stream of fluid containing relatively fewer bubbles, the first stream flowing through a bypass path that does not pass through the measurement zone, and the second stream flowing through the measurement zone of the turbidity sensor.

Abstract: Methods and systems for separating material from a host fluid use an acoustophoresis device. These methods and systems can deflect material (e.g., a second fluid, cells, beads or other particles, exosomes, viruses, oil droplets) in host fluid streams at high flow rates.

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: An acoustic standing wave is utilized to separate components from a multi-component fluid, such as oil from an oil-water mixture, or cells entrained in a fluid, 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. A driver and controller for the acoustophoretic device accommodate variable loading as the components are separated, thereby improving separation efficiency.

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: Methods are disclosed for separating beads and cells from a host fluid. The method includes flowing a mixture containing the host fluid, the beads, and the cells through an acoustophoretic device having an ultrasonic transducer including a piezoelectric material driven by a drive signal to create a multi-dimensional acoustic standing wave. A drive signal is sent to drive the at least one ultrasonic transducer to create the multi-dimensional acoustic standing wave. A recirculating fluid stream having a tangential flow path is located substantially tangential to the standing wave and separated therefrom by an interface region. A portion of the cells pass through the standing wave, and the beads are held back from the standing wave in the recirculating fluid stream at the interface region. Also disclosed is an acoustophoretic device having a coolant inlet adapted to permit the ingress of a cooling fluid into the device for cooling the transducer.

Abstract: Devices for separating a host fluid from a second fluid or particulate are disclosed. The devices include an acoustic chamber, a fluid outlet at a top end of the acoustic chamber, a concentrate outlet at a bottom end of the acoustic chamber, and an inlet on a first side end of the acoustic chamber. An ultrasonic transducer and reflector create a multi-dimensional acoustic standing wave in the acoustic chamber that traps and separates particulates (e.g. cells) from a host fluid. The host fluid is collected via the fluid outlet, and the particulates are collected via the concentrate outlet. The device is a large-scale device that is able to process liters/hour, and has a large interior volume.

Abstract: An acoustophoretic system is controlled and driven to attain a desired level of performance. An RF controller and a driver provide a frequency and power to an acoustic transducer, which can be implemented as a piezoelectric element, which presents a reactive load or a complex load. A controller implements a control technique for efficient transducer operation. The control technique can locate a frequency for operation that is at a reactance minimum or maximum for the system to produce a modal pattern and to provide efficient operation of the transducer. A method of detecting a minimum or maximum reactance in a acoustophoretic system used to trap, separate, deflect, cluster, fractionate or otherwise process particles or secondary fluids or tertiary fluids in a primary fluid and utilizing the frequency of the detected reactance to operate the acoustophoretic system.

Abstract: A system for enhancing the separation of particles or fluids from water is disclosed. A tank or bioreactor is provided with an open submersible acoustophoretic separator. The separator captures and holds fluid droplets or particles such as cells, permitting them to coalesce or agglomerate until they are large enough and have sufficient buoyant or weight force to float/sink to the top/bottom of the tank or bioreactor. In a tank or bioreactor, the separator captures and holds particles until they are large enough that their weight causes them to settle out of the host fluid. The acoustophoretic device thus speeds up separation of the particles or droplets from the host fluid.

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: Transducer assemblies that can be used in acoustophoretic systems are disclosed. The acoustophoretic systems including the transducer assemblies and methods of operating the acoustophoretic systems are also disclosed. The transducer assemblies include a housing, a polymeric film attached to the housing, and a piezoelectric material attached to the polymeric film. The piezoelectric material is not attached to, and does not come in direct contact with, the housing. The piezoelectric material is configured to be driven by a drive signal to create a multi-dimensional acoustic standing wave. The piezoelectric material can be attached to the polymer film by an adhesive coating on the polymer film.

Abstract: Acoustic perfusion devices and processes for separating biomolecules 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 series of multi-dimensional acoustic standing waves is set up inside a growth volume of a bioreactor. The acoustic standing waves are used to hold a cell culture in place as a nutrient fluid stream flows through the cell culture. The nutrient fluid stream dislodges some cells from the cell culture, which can then be recovered for cell therapy applications. The cell culture continues to expand and reproduce, permitting continuous recovery of cells from the bioreactor.

Abstract: Systems and methods for increasing the accuracy of a turbidity sensor are disclosed. The systems include a turbidity sensor and a flow module with a specialized flow path, with the turbidity sensor engaging with the flow module such that a measurement zone of the turbidity sensor is disposed within a flow path of the flow module and a bypass path of the flow module does not pass through the measurement zone. The methods include flowing a fluid containing bubbles into a system that separates the fluid in the flow module into a first stream of fluid containing relatively more bubbles and a second stream of fluid containing relatively fewer bubbles, the first stream flowing through a bypass path that does not pass through the measurement zone, and the second stream flowing through the measurement zone of the turbidity sensor.

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: 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: Multi-stage acoustophoretic devices for continuously separating a second fluid or a particulate from a host fluid are disclosed. Methods of operating the multi-stage acoustophoretic devices are also disclosed. The systems may include multiple acoustophoretic devices fluidly connected to one another in series, each acoustophoretic device comprising a flow chamber, an ultrasonic transducer capable of creating a multi-dimensional acoustic standing wave, and a reflector. The systems can further include pumps and flowmeters.

Abstract: An ultrasonic welding assembly joins bare ends of an insulated wire bundle to a wire terminal in a weldment zone by intimate contact with a sonotrode of an ultrasonic stack. A door allows the operator to place the terminal into the nest within the weldment zone. One operator hand holds the wire bundle while one contacts an external sensor. A pair of terminal clamps extend inwardly and down to secure the terminal and create a taller capture area for the loose bare wire ends. A pair of clamp finger assemblies reversibly extend towards the insulated wires away from the weldment zone for securing the wires. A wire gatherer descends upon and captures all of the wire bare ends and secures them until the horn descends, captures, and holds the wire ends in place, then extends away from the weldment zone for ultrasonic welding to commence.