Cyclone separator simulation for efficiency and pressure drop
See which particle sizes your cyclone captures, what pressure drop it costs and how the vortex behaves inside it, then compare inlet, vortex finder and cone changes before anything is fabricated.
A cyclone has no moving parts and only a few key dimensions, yet small changes to them move its performance a long way. A narrower vortex finder captures finer particles but raises the pressure drop. A longer body can help, or it can let the end of the vortex settle on the cone wall, where it wears through the metal and throws collected dust back into the gas. Empirical sizing methods give a starting point, but they assume proportions that many real cyclones, with their space limits and awkward inlets, do not follow.
More about cyclone separator simulation
Cyclone separator simulation computes the swirling gas flow inside the body, including the vortex core and the short-circuit flow that slips beneath the vortex finder. Particles across your size range are released at the inlet and followed through that flow, giving a grade efficiency curve and the cut size d₅₀, the particle size captured with 50% efficiency. The same model gives pressure drop and shows where the vortex ends and where particles concentrate at the wall.
Several geometries can be compared at the same flow rates. SixGate™’s engineers design and detail process equipment as well as simulate it, so the comparison ends with one recommended cyclone and the figures behind the choice.
Typical uses: dust collection and extraction, pneumatic conveying, spray drying and powder recovery, biomass and combustion plant, mineral processing, cyclonic vacuum cleaners and pre-separators ahead of filters.
What a cyclone study tells you
What fraction of each particle size is captured?
A grade efficiency curve from the finest to the coarsest particles in your feed, and the overall efficiency once it is combined with your size distribution.
What is the cut size?
The d₅₀, the size collected with 50% efficiency, which shows quickly whether a design is in the right range for your dust or product.
What pressure drop does it cost?
Pressure loss from inlet to gas outlet at your flow rates, also given as an Euler number, Eu = Δp/(½ρv²) based on inlet velocity, for comparison between sizes.
Where does the vortex end?
The position of the vortex end and whether it reaches the cone wall or the dust outlet, where it causes wear and re-entrainment.
Is fine dust escaping straight to the outlet?
How much gas short-circuits under the vortex finder, and how much fine material it carries with it into the clean gas.
What we model
Swirling flow and vortex structure
Tangential and axial velocity profiles, the vortex core and its movement over time, with turbulence treated to suit strongly swirling flow.
Particle separation
Particles across your size range followed through the gas flow to build grade efficiency curves and find the cut size.
Inlet design
Tangential, scroll and axial vane inlets compared, along with inlet height and width and the approach duct upstream.
Vortex finder
Diameter, insertion depth and shape compared, since this one part does much to set both cut size and pressure drop.
Cone, hopper and dust outlet
Cone angle and length, dust outlet diameter, vortex stabilisers and hopper design, judged on efficiency, vortex end position and re-entrainment.
Wall wear zones
Where particles concentrate at the wall, pointing to the areas that may need wear liners or thicker plate.
Multi-cyclone arrangements
Flow distribution between cyclones in parallel and the effect of shared inlet and outlet plenums on each unit.
Before you start
What to send us
- CAD or a dimensioned drawing of the cyclone, inlet duct and outlets (STEP or native)
- The gas, its temperature and pressure, and the range of flow rates
- Particle size distribution and density of the dust or product
- Solids loading, as a mass or volume concentration
- Target efficiency or cut size, and the allowable pressure drop
- Any space limits, wear problems or existing performance data
Does solids loading affect the result?
It can. At low loadings, particles follow the gas without changing it, which suits this kind of study well. At high loadings, particles start to alter the flow itself, and we will tell you early if your case falls in that range.
How does a smaller vortex finder change performance?
It usually lowers the cut size, so finer particles are captured, and raises the pressure drop. The simulation shows how much of each you get for your geometry, which empirical methods only approximate.
Is one large cyclone or several small ones better?
Smaller cyclones generally capture finer particles at a given pressure drop, so several in parallel can outperform one large unit. Simulation shows whether the flow divides evenly between them, which decides whether that advantage is realised.
Can you model a cyclone that underperforms in service?
Yes. A model of the existing unit usually shows why it misses its target, whether through short-circuit flow, a vortex end on the wall or a poor inlet, and which change would cost least to make.
Send us your cyclone
