Abstract: Rotor thrust balancing systems for turbomachines and methods of using the same are generally disclosed. For example, a rotor thrust balancing system for a turbomachine, wherein the turbomachine defines a centerline extending the length of the turbomachine. The system includes a rotating drive shaft, a thrust bearing, and a first waveguide sensor. The rotating drive shaft couples a turbine section and a compressor section of the turbomachine. The thrust bearing supports the rotating drive shaft of the turbomachine. The thrust bearing includes a plurality of ball bearings, an inner race coupled to the rotating drive shaft, and an outer race coupled to a fixed structure. The first waveguide sensor is coupled to the outer race at a first end of the waveguide sensor. The waveguide sensor communicates a vibrational frequency from the thrust bearing to a second end of the waveguide sensor.

Abstract: Sealing assemblies and systems and their assembly methods are provided. For example, a seal assembly is provided for use between an inner shaft and an outer shaft that are rotatable about a common axis. The seal assembly comprises a first end ring having an aft face; a second end ring positioned aft of the first end ring and having a forward face; a first hydrodynamic portion defined on the aft face of the first end ring; a second hydrodynamic portion defined on the forward face of the second end ring. A seal element is disposed between the first end ring and the second end ring such that the seal element is positioned between the first hydrodynamic portion and the second hydrodynamic portion.

Abstract: A system for managing thermal transfer in at least one of an aircraft or a gas turbine engine includes a first engine system utilizing an oil for heat transfer. The oil of the first system has a temperature limit of at least about 500° F. The system additionally includes a fuel system having a deoxygenation unit for deoxygenating fuel in the fuel system, as well as a fuel-oil heat exchanger located downstream of the deoxygenation unit. The fuel-oil heat exchanger is in thermal communication with the oil in the first engine system and the fuel in the fuel system for transferring heat from the oil in the first engine system to the fuel in the fuel system.

Abstract: A power detection device for a facility monitoring system provides non-contact power detection in a power supply line for determining a powered up or energized state of equipment connected to the power supply line. The power detection device is adapted to be disposed in communication with a live power supply line without disconnecting or interrupting the power supply to the powered equipment. A hinged casing including a sensor circuit for detecting electrical current is frictionally engaged to the power supply line by closing the hinge and drawing opposed sides of the casing together. Sensor signals are aggregated and amplified such that an amplified signal above a threshold is indicative of a current flow sufficient to power the equipment and render a determination of an energized, or “equipment on” state. Conversely, the lack of a threshold signal indicates inactive equipment such that remedial measures may be commenced.

Abstract: An apparatus and method of reducing a flow of fluid and heat between a first space and a second space in a rotatable machine and an integral seal and heat shield device are provided. The device includes an annular flange configured to couple to the rotating member of the rotatable machine and a multi-walled seal shield member extending axially from the flange. The multi-walled seal shield member is formed integrally with the flange. The seal shield member includes a first wall including a plurality of surface features, a second wall spaced radially inwardly with respect to the first wall, and a cavity formed between the first and second walls. The integral seal and heat shield device also includes a cap end integrally formed and configured to seal the first and second walls. Each of the flange, the seal shield member, and the cap end are formed of a sintered metal.

Abstract: A system for managing thermal transfer in at least one of an aircraft or a gas turbine engine includes a first engine system utilizing an oil for heat transfer. The oil of the first system has a temperature limit of at least about 500° F. The system additionally includes a fuel system having a deoxygenation unit for deoxygenating fuel in the fuel system, as well as a fuel-oil heat exchanger located downstream of the deoxygenation unit. The fuel-oil heat exchanger is in thermal communication with the oil in the first engine system and the fuel in the fuel system for transferring heat from the oil in the first engine system to the fuel in the fuel system.

Abstract: In one aspect, the present disclosure is directed to a bearing compartment sealing system including a bearing for supporting a shaft. A housing encloses the bearing and defines a compartment for holding lubricant therein. At least two seals are located between the shaft and the housing. The at least two seals, the housing, and the shaft collectively enclose the compartment. Only one of the at least two seals is a hydrodynamic seal.

Abstract: A method for determining a lowest stimulation threshold current level in a group of channels of a neuromonitoring device. The method includes stimulating tissue at a current level from a predetermined range of current levels as a sequence of pulses delivered at a frequency. The stimulating includes increasing the current level of each pulse in the sequence of pulses from an immediately preceding pulse by a first current increment. The method includes determining that a first evocation pulse from the sequence of pulses evokes a first muscular response. The method includes stimulating the tissue with a second evocation pulse from the sequence of pulses to evoke a second muscular response. The stimulating includes decreasing the frequency of the delivery of each pulse in the sequence of pulses and increasing the current level of each pulse in the sequence of pulses from the immediately preceding pulse by a second current increment.

Abstract: Devices and methods for stimulation and recording of muscle responses for determining degree of neuromuscular blockade, particularly relevant to elicitation of such responses in those under the influence of anesthesia. A system for estimating the degree of neuromuscular blockade includes at least one stimulating electrode, at least one recording electrode, a pulse generator for providing stimulation to a nerve through the stimulating electrode, and a computing device configured to: apply stimuli to the nerve according to a stimulation protocol, wherein the stimulation protocol provides a plurality of stimulation sequences that vary in frequency of pulses in the stimulation sequence, frequency of the stimulation sequences, number of pulses in the stimulation sequence, or all of the above; measure, by the recording electrode, electrical responses of a muscle; and estimate the degree of neuromuscular blockade based on changes in the electrical responses of the muscle during a stimulation sequence.

Abstract: A medical method of automatically improving signals received from a patient's physiological system can include delivering stimulation signals to a nerve pathway of a patient with electrical pulses via electrodes placed over the nerve pathway to generate a plurality of resultant electrical waveforms (EPs) based on a plurality of electrophysiological responses (ERs); recording the plurality of resultant EPs; generating an ensemble average waveform (EA), the generating comprising averaging a subset of the plurality of ERs; and denoising the EA, the denoising comprising applying a wavelet transform to the EA.

Abstract: A power detection device for a facility monitoring system provides non-contact power detection in a power supply line for determining a powered up or energized state of equipment connected to the power supply line. The power detection device is adapted to be disposed in communication with a live power supply line without disconnecting or interrupting the power supply to the powered equipment. A hinged casing including a sensor circuit for detecting electrical current is frictionally engaged to the power supply line by closing the hinge and drawing opposed sides of the casing together. Sensor signals are aggregated and amplified such that an amplified signal above a threshold is indicative of a current flow sufficient to power the equipment and render a determination of an energized, or “equipment on” state. Conversely, the lack of a threshold signal indicates inactive equipment such that remedial measures may be commenced.

Abstract: An automated evoked potential analysis apparatus for improved monitoring, detecting and identifying changes to a patient's physiological system is described. The apparatus includes an input device for obtaining electrical potential data from the patient's physiological system after application of stimulation to a patient's nerve and a computing system for receiving and analyzing the electrical potential data. The computing system includes a processing circuit configured to: generate a plurality of evoked potential waveforms (EPs) based on the electrical potential data, measure changes or trends in the generated EPs utilizing a sliding window of analysis, display incremental changes in waveforms between full subsets of EPs, and determine an alert vote for each subset, representative of changes to the physiological system generating the EPs.

Abstract: One embodiment describes a bearing damper including a housing; a damper with an annular gap and an internal spring, in which the annular gap is formed between an inner rim and an outer rim of the damper, the internal spring circumferentially bounds the annular gap, the outer rim is coupled to the housing, and the annular gap is configured to be filled with fluid used to dampen vibrations produced on a drive shaft; and an external spring coupled to the housing and to the inner rim, in which the external includes an axial stiffness engineered to externally offset axial forces exerted on the inner rim of the and a radial stiffness engineered to externally offset a first portion of radial forces exerted on the inner rim and to permit a second portion of the radial forces to propagate the vibrations from the drive shaft to the inner rim.

Abstract: An apparatus and method of reducing a flow of fluid and heat between a first space and a second space in a rotatable machine and an integral seal and heat shield device are provided. The device includes an annular flange configured to couple to the rotating member of the rotatable machine and a multi-walled seal shield member extending axially from the flange. The multi-walled seal shield member is formed integrally with the flange. The seal shield member includes a first wall including a plurality of surface features, a second wall spaced radially inwardly with respect to the first wall, and a cavity formed between the first and second walls. The integral seal and heat shield device also includes a cap end integrally formed and configured to seal the first and second walls. Each of the flange, the seal shield member, and the cap end are formed of a sintered metal.

Abstract: A bearing apparatus includes: a bearing including a first race rotatable relative to a second race, wherein the first race includes one or more drain passages extending therethrough; and a squeeze film damper connected to the first race, the squeeze film damper including first and second squeeze film spaces separated by an oil drain path which communicates with the one or more drain passages of the first race.

Abstract: A seal assembly for use between an inner shaft and an outer shaft rotatable about a common axis within a turbine engine includes a pair of end rings and a plurality of seal elements coupled between the pair of end rings. Each end ring includes a flange extending in an axial direction, and each seal element includes a pair of shoulders extending in opposing axial directions. The seal assembly also includes a pair of retaining rings. Each retaining ring is positioned between one shoulder of the pair of shoulders and a corresponding one end ring flange of the pair of end ring flanges.

Abstract: One embodiment describes a bearing damper including a housing; a damper with an annular gap and an internal spring, in which the annular gap is formed between an inner rim and an outer rim of the damper, the internal spring circumferentially bounds the annular gap, the outer rim is coupled to the housing, and the annular gap is configured to be filled with fluid used to dampen vibrations produced on a drive shaft; and an external spring coupled to the housing and to the inner rim, in which the external includes an axial stiffness engineered to externally offset axial forces exerted on the inner rim of the and a radial stiffness engineered to externally offset a first portion of radial forces exerted on the inner rim and to permit a second portion of the radial forces to propagate the vibrations from the drive shaft to the inner rim.

Abstract: This disclosure describes a surgical instrument comprising a combination femoral nerve localizer and needle placement guide instrument. The instrument may be used with a neuromonitoring system to localize and monitor the femoral nerve during a spinal procedure.

Abstract: A gas turbine engine is provided defining a radial direction. The gas turbine engine generally includes a compressor section and a turbine section, the compressor section and turbine section together defining a core air flowpath. The gas turbine engine also includes a sump positioned inward of the core air flowpath along the radial direction. An air pump is positioned inward of the core air flowpath along the radial direction for providing a flow of air from the sump to lower an internal pressure of the sump and reduce a likelihood of lubrication leaking from the sump.

Abstract: A gas turbine engine having a core engine. The core engine includes an inlet, a compressor section, a combustion section, a turbine section, and an exhaust. The gas turbine engine also includes a bearing sump arranged in the core engine for containing lubrication, the bearing sump and lubrication having an operational range between at least about 0° F. and about 550° F.