SIMULATION OF MUFFLER PARAMETERS IN VENTILATION CHANNELS OF VENTILATORS

Abstract

During long-term observation of the operation of the ventilator (artificial lung ventilation) of the UVENT-T model, a violation of repeatability was noticed under the same operating conditions. That is, on some devices of this particular model, the air flow sensor under the same conditions showed different values when repeating the measurements.Through experiments, it was established that this is caused by the unevenness of the air flow inside the ventilation channels of the ventilator, which is most likely caused by the design of the silencers installed there.The article highlights the process of research and modeling of air flow in ventilation channels of ventilators of the apparatus due to the manufacture of several test variants of muffler designs, which should solve the problem of various deviations of flow measurements. The main idea was to change the number and size of the muffler holes. Obviously, the 5 holes of 2 mm scattered the air flow too much, due to which there was an increased risk of turbulence in the air flow, which could have caused the unevenness of its measurements. Therefore, on all new mufflers, the holes were reduced to1 mm, but their number was increased by 2 times. In total, 6 design options were obtained. All 6 options were designed in CAD SolidWorks, and flow simulation was also carried out for test models. According to the results of air flow measurements, graphic dependencies were obtained for each of the silencer samples, namely the integral of the absolute error of the flow measurement, the integral of the flow noise power, the integral of the acoustic noise power and the maximum absolute error of the flow measurement.In the future, it is proposed to develop a mathematical model of laminar air flow in a ventilator taking into account new designs of silencers, as well as to develop software for testing according to the developed algorithm and model. Conduct experimental testing of designed mufflers, as well as evaluate the results of the experiment. According to the research results, a conclusion will be made about the most effective muffler design, and its design will be used inthe production of ventilators.