Fluid distribution (and its mirror image – collection) is a common requirement in a large variety of processes. In the field of chemical engineering, these processes include chromatography, ion exchange, aeration, combustion, distillation, fermentation, etc. Effective fluid distribution is equally important in other fields.
ARi is the inventor of fractal technology for distribution and collection of fluids.
These devices are based on the concept of replacing conventional distribution equipment with fractal devices which exhibit extreme symmetry over many scales.
Conventional methods used for fluid distribution typically involve a turbulent component. For example, fluid is jetted from a nozzle or orifice or the distribution is aided by splashing or stirring. Another distribution method is to add space or height to equipment so the distributed fluid eventually "spreads out". Still another distribution technique is to use high pressure drop to force an equivalence of flow to exits, again, resulting in uncontrolled jetting.
With respect to fluid scaling and distribution, fractals can be used as functional alternatives to turbulence. The uncontrolled geometry and energy dissipation characteristics of turbulence can be replaced with the precise geometry and minimal energy use of engineered fractals.
Universal path symmetry with fractal distribution
Fractal distributors are designed to exhibit extreme symmetry from large to small scale. Any individual fluid path from the center inlet to an exit point can be used to generate all other paths, to a close approximation, using symmetry operations. We refer to this property as "universal path symmetry". The resulting path symmetry provides equivalent hydraulics (equivalent flow rate, equivalent time of passage, equivalent pressure drop, etc.) to each exit or collection point. In addition to the symmetry between paths and the scaling symmetry within paths, the structures are often used as mirror image distributor and collector pairs – providing additional flow symmetry and plug flow characteristics.
As additional fractal iterations are added to the distributor, fluid flow approaches closer and closer to a perfect surface distribution or collection. There is no preference for fluid to flow to any specific area as flow rate or pressure drop are varied. The devices are also massively parallel and the total cross sectional area is increasing at the smallest scales. Therefore, pressure drop (energy use) is very low and the devices have extremely large turndown ratio – typically 10 to 1.
Another beneficial characteristic is that the devices exhibit an invariance to scaling. Larger or smaller fractals can be designed by adding or subtracting bifurcations while the symmetry of the device is maintained. This overcomes scale-up problems often encountered when taking a process from pilot to full scale operation. We have piloted fractal distributors with a diameter of a few centimeters with subsequent successful industrial scale-up to over 20 feet diameter.