摘要:
A system for cancelling or attenuating noise in at least two positive displacement compressors proximately located from each other for use with a heating or cooling system. A lead compressor and a lag compressor have a controllable rotational speed and phase of operation. A controller selectably controls the rotational speed and the phase of operation of each of the compressors. The controller controls the rotational speed of the compressors at substantially the same speed for each compressor, with a phase-lock loop and a comparator circuit for each compressor. The controller controls the phase of operation of the compressors through an oscillator so that the lead and lag compressor pressure pulses are spaced between successive outlet pressure pulses to effectively double the combined pulsation frequency for noise attenuation.
摘要:
A system is provided for attenuating noise in at least two positive displacement compressors proximately located from each other for use with at least one heating or cooling system. A lead compressor and a lag compressor have a selectably controllable rotational speed and a selectably controllable phase of operation. A controller selectably controls the rotational speed and the phase of operation of each of the compressors. The controller controls the rotational speed of the compressors at a predetermined rotational speed that is substantially the same for each of the compressors. The controller controls the phase of operation of the compressors by shifting the phase of operation of the lag compressor so that an outlet pressure pulse operatively produced by the lag compressor is substantially evenly spaced between successive outlet pressure pulses operatively produced by the reference compressor.
摘要:
A backflow and strainer device is presented. The device is a unitary unit that prevents backflow of fluid gas in a compressor and prevents dirt particles and debris from entering the compressor, thereby damaging the components. A valve mechanism moves between an open position and a closed position to either allow or prevent fluid gas from flowing into the compressor. A mesh portion is disposed in the device to trap all dirt particles and debris to prevent them from entering the compressor. The valve mechanism responds to the higher and lower pressures associated with the operation and shutdown of compressors.
摘要:
A system is provided for attenuating tonal acoustic noise associated with a single positive displacement compressor, or multiple positive displacement compressors proximately located from each other. A controller selectably controls the rotational speed and the frequency of operation of each of the compressors. The controller controls the rotational speed of the compressors about a predetermined rotational speed, in a random manner, within the pre-selected speed band to reduce the magnitude of the central tonal acoustic frequency of the pressure pulsations and disperse the sound power over a wider acoustic bandwidth.
摘要:
An economizer-equipped refrigeration system and method is provided for simultaneous operation of at least one capacity control valve controlling an independent bypass circuit with operation and variable control of the economizer circuit to permit efficient, flexible, and reliable variable system capacity control, without leakage that sacrifices system peak capacity.
摘要:
A resonator in a closed fluid system includes a body having a passageway in communication with a closed fluid system wherein a piston is movable within the passageway. Each position of the piston within the passageway defines a noise attenuation frequency corresponding to a noise frequency generated by the closed fluid system. A device providing a pressurized fluid from the closed fluid system selectively moves the piston within the passageway to vary the noise attenuation frequency.