Virtual Towing Tank Services
Our dedicated 1500 node plus computing cluster is used to simulate fluid flows around ship hullforms, submarines and offshore structures in full scale. These simulations are conducted hand in hand with our physical model testing and full scale trials to ensure that the required validation and verification is in place to give confidence in our results.
QinetiQ provides a complete suite of optimisation services which includes the ability to optimise performance using a combination of analytical methods and physical model testing.
Computational Fluid Dynamics
Our team utilises Star CCM or Ansys CFX software CFD software code running on a 1500 plus node computer cluster to conduct rapid and detailed flow assessment. CFD is routinely used to refine the design solution before building a physical model and testing in the tank facilities. Modern CFD techniques allow the capability, for example, to accurately align under water appendages for ship scale flows, including rudders, A-bracket arms, bilge keels and stabilisers as well as providing detailed wake information as input to the development of low noise propellers.
Both physical model tests and computational methods are heavily affected by boundary layer size at model scale and this is very difficult to extrapolate into full scale. This can be overcome by running CFD analysis of the hull at full scale to avoid model size problems.
The biggest challenge in predicting propeller behaviour in cavitating conditions using a cavitation tunnel is to accurately model inflow condition to the propeller. As we are interested in full scale propeller behaviour, not model scale, the inflow to the propeller has to have a full scale wake structure. CFD can predict the wake at full ‘ship’ scale and once validated by model scale wake measurement it gives the full picture of the hull wake.