Inertial deposition of particles in a bent pipe

Crane, Robert I.; Evans, Robert

doi:10.1016/0021-8502(77)90003-9

Cited by 90 publications

(40 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Using their fit suggests that particles as large as 20-30 µm will be transmitted with nearly 100% efficiency. A similar result is obtained from the simplified Crane and Evans (1977) model. It must be stressed that these fits and models are approximations and can only be used as such.…”

Section: Aerosol Samplingsupporting

confidence: 84%

Real time chemical characterization of local and regional nitrate aerosols

et al. 2009

View full text Add to dashboard Cite

Abstract. Nitrate aerosols make a very major contribution to PM 2.5 and PM 10 in western Europe, but their sources and pathways have not been fully elucidated. An Aerosol Time-of-Flight Mass Spectrometer (ATOFMS) and a Compact Time of Flight Aerosol Mass Spectrometer (C-ToF-AMS) were deployed in an urban background location in London, UK, collecting data as part of the REPARTEE-I experiment. During REPARTEE-I, daily PM 10 concentrations ranged up to 43.6 µg m −3 , with hourly nitrate concentrations (measured by AMS) of up to 5.3 µg m −3 . The application of the ART-2a neural network algorithm to the ATOFMS data characterised the nitrate particles as occurring in two distinct clusters (i.e. particle types). The first (33.6% of particles by number) appeared to be locally produced in urban locations during nighttime, whilst the second (22.8% of particles by number) was regionally transported from continental Europe. Nitrate in locally produced aerosol was present mainly in particles smaller than 300 nm, whilst the regional nitrate presented a coarser mode, peaking at 600 nm. In both aerosol types, nitrate was found to be internally mixed with sulphate, ammonium, elemental and organic carbon. Nitrate in regional aerosol appeared to be more volatile than that locally formed. During daytime, a core of the regionally transported nitrate aerosol particle type composed of organic carbon and sulphate was detected.Correspondence to: R. M. Harrison

show abstract

Section: Aerosol Samplingsupporting

confidence: 84%

Real time chemical characterization of local and regional nitrate aerosols

et al. 2009

View full text Add to dashboard Cite

show abstract

“…The sampling line was also slightly bent at two other points. For laminar flow, the inertial deposition of particles due to tube bends is given by the equation (Crane and Evans, 1977) Bend loss = Stk · 2…”

Section: Correctionsmentioning

confidence: 99%

Emission and dry deposition of accumulation mode particles in the Amazon Basin

et al. 2010

View full text Add to dashboard Cite

Abstract. Size-resolved vertical aerosol number fluxes of particles in the diameter range 0.25-2.5 µm were measured with the eddy covariance method from a 53 m high tower over the Amazon rain forest, 60 km NNW of Manaus, Brazil. This study focuses on data measured during the relatively clean wet season, but a shorter measurement period from the more polluted dry season is used as a comparison. Size-resolved net particle fluxes of the five lowest size bins, representing 0.25-0.45 µm in diameter, were in general dominated by deposition in more or less all wind sectors in the wet season. This is an indication that the source of primary biogenic aerosol particles may be small in this particle size range. Transfer velocities within this particle size range were observed to increase linearly with increasing friction velocity and increasing particle diameter.In the diameter range 0.5-2.5 µm, vertical particle fluxes were highly dependent on wind direction. In wind sectors where anthropogenic influence was low, net upward fluxes were observed. However, in wind sectors associated with higher anthropogenic influence, deposition fluxes dominated. The net upward fluxes were interpreted as a result of primary biogenic aerosol emission, but deposition of anthropogenic particles seems to have masked this emission in wind sectors with higher anthropogenic influence. The net emission fluxes were at maximum in the afternoon when the mixed layer is well developed, and were best correlated with horizontal wind speed according to the equationwhere F is the net emission number flux of 0.5-2.5 µm particles [m −2 s −1 ] and U is the horizontal wind speed [ms −1 ] at the top of the tower.

show abstract

“…Flow patterns in curved tubes have important applications to problems in engineering and aerosol science and technology, for example, heat and mass transfer (Mori and Nakayama, 1965;Dravid et al, 1971;Cheng and Takuma, 1991;Choi and Park, 1994) and analyses of particle movement in curved pipes and aerosol instrumentation (Crane and Evans, 1977;Stober and Hederer, 1978;Martonen, 1982;Willeke and Baron, 1993). Quite different from flow in a straight tube, flow in a curved tube has secondary motion in the plane perpendicular to the axial (i.e., longitudinal) motion of flow, and the axial flow itself is skewed rather than parabolic.…”

Section: Introductionmentioning

confidence: 99%