Particle Settling Velocities

Particle diameter (µm): Setting Velocity (m/s): Setting Velocity (mm/hr)
0.05 3.85E-07 1.39
0.06 4.75E-07 1.71
0.08 6.69E-07 2.41
0.1 8.82E-07 3.18
0.15 1.50E-06 5.40
0.2 2.26E-06 8.14
Typical Concept particle    
0.3 4.21E-06 15.16
0.4 6.76E-06 24.34
0.5 9.91E-06 35.68
0.6 1.37E-05 49.32
0.8 2.30E-05 82.80
1 3.48E-05 125.28
1.5 7.47E-05 268.92
2 1.30E-04 468.00
3 2.85E-04 1026.00
4 5.00E-04 1800.00
5 7.76E-04 2793.60
Typical competitor particle size    
6 1.11E-03 3996.00
8 1.96E-03 7056.00
10 3.06E-03 11016.00
15 6.84E-03 24624.00
20 1.21E-02 43560.00
30 2.72E-02 97920.00

The terminal settling velocity of an aerosol or "artificial smoke" particle increases rapidly with particle size. The settling velocity is proportional to the square of the particle diameter, although sub micron particles, such as those produced by Concept systems require the use of slip correction factors.

Calculated for standard density spheres at 293 K [20° C] and 101 kPa (1 atm).
"Aerosol Technology", William C. Hinds, Wiley-Interscience, 1999

Demonstration movies

scroll through the slides,
click on a thumnail and
view the movies

latest news

Latest News

> view all articles

Colt 4 Twin Turbo - New Product

Concept Smoke Systems are one of the leading smoke machine manufacturers... Read more >


ESS 2015

Concept are pleased to be exhibiting and supporting the Emergency Servic... Read more >

> view all

Testimonials

Building Envelope Technologies Ltd

"We have been using the ViCount unit now for some time as our main method of generating smoke for air leakage path identification as part of building airtightness tests.

The speed at which the unit builds smoke is very impressive and consistently in line with the guidance given by yourselves.

The nature and density of the smoke produced proves very effective when observed from outside the building giving sufficient time for and allowing easy observation of emerging smoke and leakage paths. The very persistent effect has allowed us to test buildings with volumes up to 40,000 m3 with just two units.

The very dry nature of smoke (i.e. small particle size) has meant that there have been no instances of contamination of the buildings following the test.

We have found the continuing technical support provided by Concept to be prompt and effective in answering queries and allowing us to get the most out of our equipment."