The design of the physical flow of in processes and process equipment is mainly based on design methods completed with experiment based coefficients. Specialised literature provides for most of these coefficients in standard solutions but is unable to cover the full scale of custom designs.
The use of CFD with or without thermal effects provides the necessary analytical tools required to design, validate, upgrade or improve custom processes and process equipment. The detailed visualisation and understanding of the complex flow and temperature distribution is the basis for an optimised design with maximum performance at minimal cost.
ACMT provides a proven track record for pressure vessels, jet-mixing reactors, oxygenation tanks and separation equipment.
Pressure vessels for the petrochemical industry are designed according to process specifications of the process owner and subject to structural approval certification by ASME, AD Merkblatt or EN.
For pressure vessels designed according to ASME div 2, FEA can be required by the client or is a mandatory requirement according to paragraph 4 or 5.
ACMT has established a proven track record of pressure vessel design validation according to ASME VIII div 2 §4 and §5, AD Merkblatt and EN. The FEA is used for nozzles, cylinder-cone and cylinder-skirt transitions and internals under internal and external design, operational and test conditions for pressure, heat and mechanical forces.
The iso-surface for product (scalar) concentration 0.5 shows the onset of the jet-mixing at the bottom of the tank. The initial fully horizontal iso-surface due to stratification of both components, starts to wrap when the impulse of the mixing jets push the lower component upwards and sucks the higher component downwards.
This image is of a 15 000m³ tank where the mixing time was reduced by 50% by the use of CFD to attain a 0.12% difference in homogeneity between top and bottom.
The scalar concentration gradient for a mixing of three products of which one has a relative volume of less than 1/1 000 000 compared to the largest fraction, is difficult to simulate, especially when the diffusivity between the different products is set to zero.
This image, at the start of mixing process, is of a small 10m³ batch reactor which is filled, mixed and emptied as part of a continuous process in less than one hour.
Land based fish farms and ships for transporting live fish, require not only an adequate supply of oxygen-rich water but also a perfect distribution in the entire volume of the tank or cargo. A perfect homogeneous distribution of fresh, oxygen-rich water reduces stress and allows for maximum fish density.
ACMT was commissioned by a major salmon producing company in Norway to analyse the fresh water flow and oxygenised recirculation flow in their transport ships. Based on this research, a new layout was proposed for the redistribution of the inlet jet to optimise the homogenisation of the oxygen-rich water in the cargo.
The design of a sedimentation tank with limited dimensions for the separation of particels < 10 μ with a relative density < 3 is very difficult when the continuous proces outflow is high.