Cavitation is among the most critical and costly phenomena in fluid-flow turbomachinery. It limits the operating range, reduces efficiency, causes noise and vibrations \u2013 and in the worst case, can lead to irreversible material damage within a short period. CFD-based cavitation simulation is currently the most reliable tool for effectively addressing this phenomenon even during the design phase.<\/p>\n\n\n\n
Cavitation<\/strong> describes the local evaporation of a liquid due to a pressure drop below the vapor pressure-dependent boiling point \u2013 without a temperature increase. In turbomachinery, this pressure drop typically occurs at points of high flow velocity: on the suction side of pump impellers, at the pressure edge of propeller blades, or in tight clearance areas.<\/p>\n\n\n\n The resulting vapor bubbles collapse abruptly as soon as they reach areas of higher pressure. This collapse creates:<\/p>\n\n\n\n The Cavitation is a limiting phenomenon for turbomachinery<\/strong>, that operate in liquids. For predicting the onset of cavitation and its effects on machine performance, the CFD simulation as the most reliable method<\/strong> Einsatz. Affected are almost all machine types in which liquids are accelerated or redirected:<\/p>\n\n\n\n modern CFD cavitation models are based on a Two-phase approach<\/strong>: The flow is modeled as a mixture of liquid and vapor phases, with the local vapor fraction governed by a transport equation. Established modeling approaches include:<\/p>\n\n\n\n The cavitation model is supplemented by suitable Turbulence models<\/strong> (k-\u03c9 SST, k-\u03b5 Realizable) and \u2013 if necessary \u2013 by models for thermal effects that become relevant with cryogenic fluids or hot water.<\/p>\n\n\n\n A carefully set up cavitation simulation provides much more than just a statement about whether cavitation occurs. Typical results include:<\/p>\n\n\n\n Our cavitation simulations are fully performed with Open-source software<\/strong> carried out \u2013 primarily with OpenFOAM<\/strong> and embedded in the automated InsightCAE Workflow<\/strong>:<\/p>\n\n\n\n The true strength of CFD-based cavitation analysis lies not just in diagnosis\u2014but in Optimization<\/strong>. Based on the simulation results, specific design measures can be identified and evaluated:<\/p>\n\n\n\n In combination with our automated optimization framework, many geometry variants can be systematically investigated for their cavitation behavior \u2013 without additional manual effort for each variant.<\/p>\n\n\n\n Cavitation in turbomachinery is not an uncontrollable fate\u2014it is predictable, localizable, and can be controlled through targeted design measures. CFD cavitation simulation based on OpenFOAM offers the most accurate and cost-effective tool for this purpose: it requires no license fees, is fully automatable, and can be integrated directly into the design process.<\/p>\n\n\n\n\n
Cavitation as a limiting phenomenon for turbomachinery<\/h2>\n\n\n\n
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Cavitation Simulation with CFD: Physical Fundamentals<\/h2>\n\n\n\n
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What specifically does CFD cavitation simulation achieve?<\/h2>\n\n\n\n
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Our Workflow: Cavitation Simulation with Open-Source Software<\/h2>\n\n\n\n
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Cavitation simulation as a basis for cavitation-resistant design<\/h2>\n\n\n\n
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Conclusion: Calculate cavitation before it causes damage<\/h2>\n\n\n\n