Cyclone separator proportions: Stairmand high-efficiency and Lapple conventional — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/cyclone-separator-proportions/  (sheet CC BY 4.0)
Basis: Published ratios: Stairmand 1951, Lapple 1951, as tabulated in Utikar et al. 2010, Grave et al. 2021 and Dartmouth ENGS 37 notes
Catalog version: 2026-10-20

Sizes: see table below
- Reference geometry from published ratios; no efficiency claim. A reverse-flow cyclone is sized by its barrel diameter D: every other dimension is a fixed ratio of D for a given family. Gas enters tangentially through a rectangular inlet, spirals down the barrel and cone, and leaves upward through the vortex finder; the separated dust leaves through the bottom outlet.
- Stairmand (1951) high-efficiency and Lapple (1951) conventional ratios as tabulated by Utikar et al. (2010, after Leith & Licht 1972), Grave et al. (2021, Stairmand only) and Cushman-Roisin (Dartmouth, after Cooper & Alley). Utikar et al. print the Lapple cylinder height as 1 D; the other tabulation prints 2 D with a 2 D cone and H = 4 D, which is what is used here.
- Files: D = 100 and 150 mm for both families. D, a, b, De, S, h, H and B are gas-side (inside) sizes; the wall is added outside them. The wall (2 mm, normal to the cone too) and the inlet duct run (1 D from the barrel centre plane, open end) are example parameters, not part of the published ratios. The vortex finder is a plain tube De inside, flush with the top of the roof; the inlet's outer wall is tangent to the barrel and its top is level with the roof.
- Material-neutral: the files are shapes. Wall thickness, joints and outlet connections are yours to choose.

dimension  Stairmand HE  Lapple  Stairmand at D = 100 / 150  Lapple at D = 100 / 150
a: inlet height  0.5 D  0.5 D  50 / 75 mm  50 / 75 mm
b: inlet width  0.2 D  0.25 D  20 / 30 mm  25 / 37.5 mm
De: vortex finder (gas outlet) diameter  0.5 D  0.5 D  50 / 75 mm  50 / 75 mm
S: vortex finder length below the roof  0.5 D  0.625 D  50 / 75 mm  62.5 / 93.75 mm
h: cylinder (barrel) height  1.5 D  2 D  150 / 225 mm  200 / 300 mm
H: overall height, roof to dust outlet  4 D  4 D  400 / 600 mm  400 / 600 mm
B: dust outlet diameter  0.375 D  0.25 D  37.5 / 56.25 mm  25 / 37.5 mm
cone height (H − h)  2.5 D  2 D  250 / 375 mm  200 / 300 mm

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- InTech (open access): Utikar et al., Hydrodynamic Simulation of Cyclone Separators, in Computational Fluid Dynamics (2010), Table 1 — web — Open access chapter; ratios are facts — https://cdn.intechopen.com/pdfs/6738/InTech-Hydrodynamic_simulation_of_cyclone_separators.pdf
- EPJ Web of Conferences (open access): Grave, Paulo, Petit, Irassar, Optimal design of cyclones in series ..., EPJ Web Conf. 249, 12003 (2021), Table 1 — web — CC BY 4.0; ratios are facts — https://www.epj-conferences.org/articles/epjconf/pdf/2021/03/epjconf_pg2021_12003.pdf
- Dartmouth College (ENGS 37 course notes): B. Cushman-Roisin, Cyclones: standard cyclone dimensions (Stairmand 1951, Lapple 1951, Swift 1969) — web — Publisher's page; dimensions are facts — https://cushman.host.dartmouth.edu/courses/engs37/Cyclones.pdf

Free files (CC BY 4.0, Xem Studio; STEP + STL, 4 parts): https://xemstudio.com/files/hardware/cyclone-separator-proportions/index.json
API: https://xemstudio.com/api/geometry?object=cyclone-separator-proportions