"Towards Direct Numerical Simulation of Compressible Orifice Flow"
, in ASME: Proc. of the ASME/BATH 2013 Symposium on Fluid Power & Motion Control - FPMC2013, October 6-9, 2013, Sarasota, Florida, USA, 10-2013
Towards Direct Numerical Simulation of Compressible Orifice Flow
Sprache des Titels:
Proc. of the ASME/BATH 2013 Symposium on Fluid Power & Motion Control - FPMC2013, October 6-9, 2013, Sarasota, Florida, USA
Simulation methods from simple lumped parameter approaches to complex computational fluid dynamics codes have become a widely used tool in the fluid power community. Certain tasks like
the predicition of flow forces on the control spools in valves or the design of port plates in axial piston pumps are usually treated
by the aid of numerical simulation. Like in many other cases, the underlying principle is the control of flow by orifices. The importance of orifice flow for hydraulic systems is reflected by
the vast number of publications on various aspects of orifice flow in the fluid power literature. In lumped parameter simulations, the orifice equation giving the flow rate as a square root of the
pressure drop is widely used even in transient cases where it is not clear whether the flow develops fast enough to justify the assumption of stationary flow. On the other end of the model complexity spectrum computational fluid dynamics codes are used in the fluid power community. These very complex models require a high number of parameters for the tuning of turbulence models,
wall models, and the like. The quality of the results heavily dependes on a good choice for these parameters. Additionally, the
vast majority of turbulent flow simulations is done with the assumption of an incompressible fluid. Very often, the results from
simulations deviate heavily from measurement results and only after parameter tuning a good match between model and simulation is achieved. This paper suggests the use of direct numerical
simulations for simple and prototypical geometries in order to gain a better understanding for transient orifice flows lacking the fully developed flow assumed in traditional models.