Fluid Power Simulation and Modeling
The Fluid Power libraries offer elements for the efficient and intuitive modeling of fluid-power systems and components. Users are able to create their models in a straightforward manner according to the hydraulic or pneumatic circuit diagram. The models are assembled from library elements such as cylinders, valves, pipes, hoses, pumps and accumulators.
The fluid power models in SimulationX consider the extreme nonlinearities such as the pressure-, temperature- and gas-fraction-dependent fluid properties, nonlinear valve properties, temperature influences and changes, aeration and cavitation, as well as volumetric and mechanical efficiencies. If one- and two-phase behavior of fluids and gases is to be examined, the Fluid Power domain is amended by the domain Thermodynamics. The fluid power libraries interact with models from the domains Mechanics, Power Transmission and Controls. This permits the simulation of complex multi-physics models.
SimulationX Fluid Power Libraries
The Hydraulics library is applied to the simulation of complete hydraulic plants as well as components (such as valves), using models with varying degree of detail. Input parameters for each element are kept as simple as possible and close to the technical device, such as the data sheet information and geometry. Depending on the available parameter knowledge the user can chose between different model descriptions for one and the same physical phenomenon, such as the flow resistance and friction behavior of a hydraulic component. The fluid properties required in the simulation are computed as functions of pressure, temperature, and gas fraction and are stored in a comprehensive and user-expandable fluid database.
Using the pneumatics library, tasks in the fields of pneumatic drives and handling equipment, hydro-pneumatic accumulators and shock absorbers, or fuel cells and chemical process equipment are efficiently solved. The pneumatics library allows simulating systems operating on pure gases as well as mixtures. All resistance models include laminar as well as turbulent losses. Furthermore, all pneumatic resistances distinguish between sub-critical and super-critical flow behavior. The gas properties are calculated as functions of pressure, temperature, and mixture composition. Several different gases and mixtures can be used within one model. The gas properties are defined in a comprehensive and user-expandable fluid database.
The ITI FluidDesigner supplements the Hydraulics and Pneumatics libraries as a comfortable tool for the creation and editing of user-defined fluids. It allows an efficient description all physical fluid properties (such as viscosity, density, and compressibility), which are relevant for dynamic simulation. The fluid properties are defined as dependencies of pressure, temperature, and gas fraction. Supported by an already existing classification of fluids suitable default properties are proposed, which simplifies the creation of user-defined fluids. The provision of manifold alternative parameterization options (numbers, arbitrary functions, multi-dimensional characteristic data sets) ensures a maximum flexibility.