Inlet or exhaust line for a reciprocating machine
AssigneeCentre National de la Recherche Scientifique (CNRS)
InventorsJean-Laurent Peube, Jacky Tartarin, Janick Laumonier
Life of this patent
Estimating the term…
Abstract
An inlet or exhaust line for a reciprocating machine attenuates the sound level of the machine while being simple and economical to produce. A sensor measures the instantaneous flow rate of gases passing through the line while a restriction device variably restricts the cross-section of the line as a function of the instantaneous flow rate measured by the sensor. Material for absorbing acoustic energy covers the internal wall of the line.
Claims8
An exhaust line, especially for a reciprocating machine, comprising;
- a gas flow pipe fitted with at least one measurement sensor for measuring a physical quantity characteristic of the instantaneous flow rate of the gases;
- the exhaust line further including at least one restriction device for variably restricting a cross-section of the exhaust line and controlling passage of the gases, said at least one restriction device instantaneously varying energy loss of the gases flowing in the pipe as a function of the quantity measured by the at least one measurement sensor in order to reduce low-frequency pulsations of the gases and low-frequency components of noise which results from the presence of low frequency pulsations of gases in the exhaust line;
- an internal wall of the gas flow pipe lined with a material capable of absorbing the low frequency components of noise in order to attenuate high-frequency pulsations of the gases, as well as high-frequency components of the noise generated in the pipe by the at least one restriction device;
- the exhaust line further including an electronic device for analyzing the signal output by the at least one measurement sensor with a view to detecting and optionally diagnosing a malfunction of the reciprocating machine.
An exhaust line, especially for a reciprocating machine, comprising;
- a gas flow pipe fitted with at least one measurement sensor for measuring a physical quantity characteristic of the instantaneous flow rate of the gases;
- the exhaust line further including at least one restriction device for variably restricting a cross-section of the exhaust line and controlling passage of the gases, said at least one restriction device instantaneously varying energy loss of the gases flowing in the pipe as a function of the quantity measured by the at least one measurement sensor, in order to reduce low-frequency pulsations of the gases and low-frequency components of noise which results from the presence of low frequency pulsation of gases in the exhaust line;
- an internal wall of the gas flow pipe lined with a material capable of absorbing the low frequency component of noise in order to attenuate high-frequency pulsations of the gases, as well as high-frequency components of the noise generated in the pipe by the restriction device;
- the exhaust line equipping a motor vehicle, and the at least one restriction device incorporating the speed of movement of the vehicle as an additional parameter in order to attenuate as much as possible the exhaust noise of the engine when the vehicle is moving at low speed and in order to minimize the pressure drops of the exhaust gases, so as to improve the performance of the combustion engine when the vehicle is moving at high speed.
Dependencies are inferred from the claim text.