By simulating the membrane, valves and fluid dynamics in an artificial ventricle using Ansys Fluent and Ansys LS-DYNA, researchers developed a computational model able to accurately reproduce the blood flow inside the left chamber of a total artificial heart, together with the displacement of the aortic and mitral valves and the membrane. Results from fluid–structure interaction simulations led to realistic analysis of the motion of the valve leaflets and membrane.
Moving the wall boundaries of a fluid domain during a CFD simulation is still a big challenge, particularly for cardiovascular applications. Engineers used Ansys Fluent, Ansys Mechanical and RBF Morph to perform cardiovascular simulation with moving walls and applied it to the fluid–structure interaction analysis of a custom valve coupled with patient data. They developed a high-fidelity, fast and accurate way to bring simulation into the clinic.
Unexploded landmines are a massive problem in some countries. Conventional radar is not able to detect them because they are often housed in plastic containers. Using Ansys HFSS to obtain the radar cross section of a 330 ml plastic soda bottle filled with dielectric materials to mimic explosives, engineers were able to apply machine learning techniques to predict whether a bottle detected underground is a landmine or not.
A small internal cavity in a high temperature copper ingot can cause a very costly production shutdown. Engineers developed an electromagnetic detector to sense cavities during production using Ansys Maxwell to check the coil configuration and induced currents; Ansys CFD to monitor the detector’s behavior at extreme temperatures; and Ansys Mechanical to determine whether thermal and pressure effects could damage the electronics. The detector paid for itself in the first month in operation.
Astec, Inc. engineers identified an opportunity to optimize the hot mix asphalt aggregate drying process where the phase change of liquid to gas can consume half the energy input. By developing software that captures the mass transfer between aggregate particles — in addition to momentum and energy exchange between the fluid phase solved by Ansys Fluent — they designed a more efficient dryer that gives them and their customers a competitive advantage with lower running costs and reduced emissions.
Flutter, the self-excited vibration due to fluid–structure interaction in rotating machines, can lead to blade loss and damage to large-scale turbomachinery. To develop a flutter-free blade, engineers created their own FLTR tool for automatic blade flutter prediction in Ansys CFX, which led to a reduction in simulation time by 60% and in pre- and post-processing time by 95%. This tool could accelerate the development of the flutter-free blade.
To check the accuracy of simulation versus experimental results for wind turbines, engineers used Ansys CFX for the numerical simulation of vertical and horizontal axis wind turbines. CFX velocity distribution results were in very good agreement with the calibrated wind tunnel tests for a variety of turbulence models.
Air quenching instabilities in internal combustion engines can lead to catastrophic failures within a combustion chamber due to intense pressure fluctuation and acoustic wave resonation. A 2D transient simulation of flame instability in a Rijke tube using Ansys Fluent enabled engineers to study the acoustic wave formation and temperature release throughout the flow region in an effort to reduce flame instability issues.
Motorcycle exhausts with no catalytic convertors vent a large amount of pollutants into the atmosphere. Using Ansys Fluent to study the flow through a custom-made multi-chamber muffler, engineers were able to monitor the chemical reaction between carbon monoxide and oxygen for different mixtures of the two gases in the muffler, in an effort to reduce pollution.
To study air blast shock scaling, engineers used Ansys AUTODYN to simulate an explosion of 5 grams of C4 explosive in a tube 15 feet long and 6 inches in diameter. Simulations provided data of shock propagation through the tube that accurately predicted the blast profile observed in experimental testing.
Restenosis is the narrowing of a blood vessel that has previously been treated to remove a blockage. Patient-specific geometries based on ultrasound images of arteries experiencing restricted blood flow from restenosis were modeled in Ansys Fluent. Simulating the fluid dynamics within peripheral arteries can help predict device or treatment failure without using invasive methods.
To study residual stresses in welding, engineers created finite element models of a tube-to-plate welded joint, and performed sequentially coupled thermomechanical full transient analysis using Ansys Mechanical. They were able generate a predictive model for residual welding stresses that closely matched experimental results obtained using strain gauges and thermocouples.
The problem of flame stability in supersonic parallel flow is a major concern. Shock impingement from the walls causes a separation bubble to form at the flame region, which makes the flame unstable. Ansys Fluent simulations revealed the location of the separation bubble inside the combustor body. Flame stability was achieved using a species transport model by calculating the molar fractions of different species.
A modern helicopter needs a large number of interference-free, high-frequency systems for communications and other purposes. To save time and costs, engineers performed an interference analysis using Ansys HFSS SBR+ to choose the best possible positions of the different antennas, without the need for lengthy physical positioning and testing of the antennas.
Billet transfer cars are crucial in integrated steel production plants. Engineers modeled the car’s drive mechanism, gearbox and suspension systems in Ansys Spaceclaim Design Modeler to pinpoint all possible failure scenarios, followed by Ansys rigid body dynamics simulations. They found a suspension system malfunction that was impossible to discover by routine maintenance inspections, and extended the lifetime of their billet transfer cars.
To evaluate the temperature rise of enclosed switchgear exposed to the sun, engineers simulated the effects of solar radiation and the rated current load. They used Ansys Mechanical APDL to calculate losses caused by the rated current load and Ansys CFX to determine the temperature rise of the closed gas tank filled with insulating gas. The result was a convenient tool to predict the temperature of switchgear exposed to extremely hot conditions.
In aerospace systems, control gap seals isolate the bearing chamber from the secondary air system to avoid oil contamination. Using Ansys Fluent to simulate the spreading of an oil drop under a pressure differential that increases with time, engineers found that the droplet can resist aerodynamic forces until a certain pressure drop value. Once that pressure barrier is broken, the oil spreads and is pushed out of the domain.
Ansys Fluent and Ansys EnSight gave engineers a look into a new, patented system for spray drying using electrostatics. Simulating the low-temperature spray drying of whey slurry (50% whey /50% water) through four nitrogen-assisted electrostatic nozzles, they found that the slurry dried rapidly, with the majority of particles impacting tower walls as fully dried powder.
In the early stages of the design of the First Narrows pumping station in Vancouver, B.C., engineers simulated the hydrodynamic conditions of the proposed pumping system and wet well design under the station’s normal operating conditions using the k-epsilon turbulence model coupled with the volume of fluid (VOF) method in Ansys Fluent. This saved costs with less turnaround time compared to physical/scale model testing and produced reliable results.
To understand the thermal effects and forces on their C4M space launch vehicle, engineers used Ansys Fluent to model the flame trench and launch vehicle during ignition, lift-off and flight, when flame temperatures can reach 3,800 K. They accurately determined the locations and magnitudes of the maximum pressure and thermal loads on the structures to optimize the design and materials selection.