• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2004년도 춘계학술대회
• /
• pp.1963-1968
• /
• 2004

A collection efficiency of cyclone is influenced by cut-size and slope of grade efficiency curve. It has been recognized that the collection efficiency is improved when the cut-size is reduced. However, effects of the slope have never been studied so far. In this study, we analyze a relationship between slope of grade efficiency and collection efficiency in two-stage cyclones. In single stage cyclones, higher slope cyclones have high efficiency. On the contrary to single stage cyclone, collection efficiency of two-stage cyclone have the maximum value when the first cyclone has a lower slope and second cyclone is high.

• 한국가시화정보학회지
• /
• 제18권3호
• /
• pp.90-95
• /
• 2020

The purpose of this study is to numerically evaluate the collection performance of an ultra-small Lapple cyclone separator for 1~10 ㎛ particles introduced at flow rate of 10 L/min. The numerical evaluation reveals that a static pressure drop occurs more dominantly inside of the cyclone separator than at the inlet and the vortex finder. Also a fluid flow in the cyclone separator is confirmed to have a helical structure heading upward in the center of cyclone separator and downward in the vicinity of wall. The investigation on dust collection efficiency of the Lapple cyclone separator shows that particles of 4~8 ㎛ diameters are collected at very lower efficiency than other sizes. Then, the cut-point diameter of the cyclone separator is 1.48 ㎛.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2003년도 춘계학술대회
• /
• pp.2227-2232
• /
• 2003

For a reasonable analysis of grade efficiency of cyclone separator, in-line measurements of particle size and particle concentration are needed. The purpose of this study is to define the correlation of measurement data and to measure grade efficiency and pressure drop. The authors adapted that the grade efficiency could be calculated directly from the counted particle numbers. The problem of collection efficiency calculation was different from counting rate of aerosol counters under the same conditions. It is important factor to use the rate of the particle counters to obtain reliable results. Therefore, the authors should use and calculate compensation factor considering sensitivity of aerosol counters, gas velocity and concentration affect higher 30% than originally measured grade efficiency. As the pressure drop and grade efficiency increase, as flow rate increase and then also pressure drop and grade efficiency increase.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2004년도 춘계학술대회
• /
• pp.1969-1974
• /
• 2004

The performance of small cyclone is analysed by an experiment for the purpose of developing a bag-less vacuum cleaner. For the high collection efficiency and low pressure loss cyclone, the effect of cyclone inlet feature must be well understood. Four types of the helical inlet are considered to compare with the normal tangential inlet, and also various inlet velocities are used to each inlet type. Based on the reference dimension, each type of inlet shows the changes of the grade efficiency and pressure loss which determine the cyclone quality. The results show that the helical inlet has the smaller cut-size but bigger pressure loss than the tangential inlet. And the degree of opening area influences factors of cyclone performance. As the inlet velocity is increased, the cut-size becomes smaller and the pressure loss becomes bigger of each cyclone. Further studies are required to understand the optimized helical inlet of cyclone.