Prediction of Particle-Collection Efficiency for Vacuum-Blowing Cleaning System Based on Operational Conditions

Abstract

<jats:p>The dust-collection system, as the core of a sweeper vehicle, directly inhales dust particles on the pavement. The influence of variable operational conditions on particle-separation performance was investigated using computational fluid dynamics (CFD) Euler–Lagrange multiphase model. The particle-separation performance efficiency and retention time were used to evaluate the dust-collection efficiency. The uniform design (UD) and multiple regression analysis (MRA) methods were employed to predict and optimize the effects of reverse-blowing flow rate, pressure drop, and traveling speed on separation efficiency. The results indicated that the dust-collection performance initially increased and then decreased with increasing reverse-blowing flow rate. As the pressure drop increased, there was an increase in total dust-collection efficiency. However, the efficiency decreased with increasing traveling speed. The regression model showed that the proposed approach was able to predict the particle collection efficiency accurately. In addition, the optimum operational conditions were obtained, namely a reverse-blowing flow rate of 2100 m3/h, a traveling speed of 5 km/h, and a pressure drop of 2400 Pa. The maximum particle-separation efficiency was 99.10%, which showed good agreement with the experimental results.</jats:p>

Enhancement of particle collection efficiency considering the structural interplay: particle motion characteristics analysis

“…Where u * is the friction velocity, y is the distance to the nearest wall, and v is the local kinematic viscosity. We find that the grid y+ of the boundary layer is 3 in our published paper [23]. It is suitable for the simulated calculation of vacuum-blowing cleaning system.…”

“…Under the action of the applied blowing force, the negative pressure generated by Suction-inlet can suck the particles up easily with lower pressure. In our previous published papers, we have clarified the mechanism of the reverse blowing flow rate that acted on the Blowing-inlet, and we also calculated the optimized results [23]. So the Blowing-inlet helps enhance the cleaning efficiency and reduces the consumption of energy for centrifugal fan.…”

“…There has no critical value of the retention time after which particles cannot be collected [22,23]. In order to realize the synchronous transportation of different-sized particles in the industrial process, it is necessary to match the mean residence time of different-sized particles with the transportation completion time [35,36].…”

“…The traditional vacuum type only utilizes the negative pressure delivery theory. We have proposed a novel structure which utilizes both negative and positive pressure mixed-delivery theory [23], and we call this novel structure the vacuum-blowing cleaning system. The particle behavior is more complicated in the mixedpressure field.…”

Flow and Noise Characteristics of Centrifugal Fan in Low Pressure Environment

“…For every 1000 m increment in altitude, the atmospheric pressure drops by about 10 kPa, and the air density also gradually decreases. When the altitude is 5000 m, the air density is 0.7263 kg/m 3 , which is only about half of that in the plain area [1,2]. However, from the sea level to the elevation below 85,000 m, the volume ratio of the main gases such as nitrogen and oxygen is basically the same at each altitude.…”