Operating Flow & Particle Parameters
Define gas volumetric flow rate, temperature, particle density, and geometry.
Cyclone Sizing & Separation Results
Live calculated barrel diameter, cut size d50, pressure drop, and efficiency.
Cyclone Separator Aerodynamics & Cut Size Derivations
For a standard tangential cyclone separator, the barrel diameter \(D_c\) is calculated from the gas volumetric flow rate \(Q\) and target inlet velocity \(v_i\) based on the rectangular inlet area \(A_{in} = a \cdot b = (a/D_c)(b/D_c) D_c^2\):
The effective number of spiral turns \(N_e\) executed by the gas stream in the outer descending vortex is:
Balancing the outward centrifugal force on a solid particle against Stokes inward radial aerodynamic drag yields the classic Rosin-Rammler-Intelmann cut size \(d_{50}\):
The grade-efficiency function \(\eta(d_p)\) for any particle diameter \(d_p\) follows the Barth/Leith-Licht sigmoidal curve:
Cyclone static pressure drop \(\Delta P\) is expressed in terms of the inlet velocity head:
5 Fatal Engineering Traps in Cyclone Separator Design
1. Air Inleakage into the Bottom Dust Discharge Hopper (Vortex Core Re-entrainment)
Allowing ambient air to infiltrate through worn rotary airlock seals or leaky dump valves beneath the conical apex. Because the core of the cyclone operates at a strong negative vacuum, incoming air creates a high-velocity upward jet through the dust cone, sucking settled fines straight into the inner vortex. Overall collection efficiency drops from 94% down to under 50%.
2. Operating at Hyper-Velocities (> 24 m/s) Triggering Saltation Re-entrainment
Designing with excessively high inlet velocity in an attempt to capture sub-micron dust. Beyond 22–24 m/s, violent wall boundary layer turbulence scours already-deposited particles off the cone walls ("saltation"). Furthermore, pressure drop escalates with \(v_i^2\) and abrasive wall wear accelerates with \(v_i^3\), cutting through 6 mm AR steel plates in months.
3. Moisture Condensation Causing Mud-Caking and Asymmetric Vortex Precession
Failing to thermally insulate the cyclone casing when handling humid process gases (e.g. spray dryers or wood pellet dryers). Wall temperatures dropping below the water or acid dew point cause fine dust to bake into a dense mud crust. This asymmetric buildup disrupts the circular vortex boundary, causing violent pressure pulsations that shake ductwork.
4. Overfilling the Dust Hopper past the Conical Discharge Apex
Failing to empty the dust hopper continuously or operating with a jammed discharge valve. As dust levels rise past the hopper flange into the conical apex, the high-speed spinning vortex core directly contacts the stationary dust bed, scouring hundreds of kilograms of powder into the clean gas exhaust within minutes.
5. Paralleling Multiple Cyclones without Balanced Inlet Ductwork
Connecting multiple cyclones to a single header without symmetrical splitters. Flow inevitably maldistributes; the lower-flow cyclone experiences velocity decay below 12 m/s, losing its vortex and dumping uncollected dust directly into the stack, while the overloaded cyclone suffers extreme pressure drop.