Altair Hyperworks - A Platform for Innovation™

FSI Simulation of Airfoil Using AcuSolve and RADIOSS. AcuSolve was used to simulate the hydrodynamic damping of water flowing over an flexible airfoil using the Practical Fluid Structure Interaction technology. The airfoil was excited by applying an initial displacement to the first mode, then letting it naturally decay. The added mass of surrounding water makes this a challenging FSI application from a numerical stability standpoint. The modal data for the analysis is provided by RADIOSS in OP2 format. The hydrodynamic damping ratio is calculated by evaluating the logarithmic decrement of the displacement time history plot from a monitor point placed on the airfoil surface.

Wind Turbine FSI AcuSolve has been used to simulate the Fluid Structure Interaction of a rotating wind turbine model. The model consists of a 2-bladed twisted and tapered rotor design that is operating with a constant rotational speed and steady inflow. The complex flow structures along the blade lead to unsteady aerodynamic forces that give rise to vibration and unsteady loading.

Wind Turbine Micro-siting and Wake Propagation AcuSolve has been used to perform detailed micro siting calculations of candidate wind park terrain. In addition to providing detailed flow profiles over complex terrain AcuSolve can be used to optimize turbine placement and power output by looking at the wake propagation downstream of the turbines.

Corrugated Pipe Modeling Turbulent fluid flow and pressure drop are sources of concern in corrugated flexible pipe that is used to transport refined oil and liquefied natural gas (LNG). Due to the complex physics, the empirical pipe flow models yield a great uncertainty in the validity of pressure drop and thermal predictions. The turbulence models available in AcuSolve provide accurate predictions of pressure drop, which compare reasonably well with the experimental tests of corrugate pipes. AcuSolve can offer guidance on design variations and can improve the full scale design of offshore transport system.

Airflow and Temperature Stratification in Buildings A pre-construction phase CFD analysis was conducted using AcuSolve for a skyscraper atrium to determine airflow and temperature levels during winter and summer conditions. Airflow requirements, vent locations and heating requirements were optimized to conform to building code standards for human comfort. ( Courtesy of Dr. Kishan Padakannaya ).

Shock Absorber Valve. JSOL Corporation and KYB Corporation collaborated to solve the valve deflection in a shock absorber. AcuSolve's Practical Fluid Structure Interaction methodology computed the deflection based on 13 mode shapes computed by NASTRAN. The gap between the valve and the piston ranged from 0.010 mm - the initial gap - to 0.117 mm.

Tube-Fin (Plain) Heat Exchanger. ACUSIM Software Inc. and API Heat Transfer collaborated for solving unsteady flow and heat transfer in staggered tube bundles with external fins. The methodology accurately computed friction (f) and Colburn (j) factors of a plain fin with a staggered tube arrangement. It can be easily extended to other fin types. The solution corresponds to bench mark data from Kays and London.

Chemical Mixing. Mixing operations are used across a wide spectrum of process industries: pharmaceutical, chemical, personal care products, biotechnology, food and beverages, paper pulp, oil, rubber, ceramics, and waste disposal, just to name a few. ORCA™ is a fully integrated GUI based mixing package designed to analyze these processes. It combines the computational power of AcuSolve, the intuitive pre and post processing capabilities of ICEM CFD, the extensive mixing knowledge and experimental validation of Mixing Consultant Inc.

Train Aerodynamic Interaction. Passing trains can generate strong aerodynamic forces. We have used CFD techniques to predict the dynamic forces for a high-speed train passing other rail cars. The aerodynamic loads are used to evaluate the risk of accidents such as damage to commuter rail windows or dislodging freight containers. (Courtesy of Redwing Engineering.)

Design of Blood Handling Devices. CFD is an effective tool for the complex design problem of blood pumps. We first solved a complete blood pump design analysis for our client to demonstrate the use of CFD in design. We also developed a software module to predict the blood damage, an important design criteria. We then assisted the client in developing a continuing in-house CFD design capability combining both software and hardware. (Courtesy of Applied Research Associates.)

Automotive. AcuSolve is widely used by the automotive industry to analyze vehicle designs, specifically in the area of climate control and underhood cooling systems. With AcuSolve, automotive companies and their suppliers can test cooling system designs without having to tool or experimentally test prototypes, thus saving time and resources, as well as speeding up the design process.

Electronic Cooling. As computers and electronic devices become faster and more powerful, thermal management gains ever increasing importance. It is no longer sufficient to use the rule of thumb to design for thermal integrity, but rather detailed and accurate simulation is required. AcuSolve is used by Electronics industry to analyze the thermal dissipation at the system as well as component levels. (Courtesy of SGI.)

Blood Pump Design Optimization. Computational tools can be used to optimize performance in blood pumps. We are using advanced CFD codes to calculate the flow of blood through pumps combined with blood damage models to predict hemolysis. The resulting tools can be used to evaluate and optimize a blood pump to both minimize blood damage and optimize pump performance. (Courtesy of Applied Research Associates.)

Process Intensifier. Before one can optimize any mixing system, one first needs to know what is the current mixing. A study of 4 currently commercially available pipe mixers or inline mixers was initiated. Because the line mixers are inside the pipe, they are the mixing version of a black box. Do they really mix? Are they any good at what they do? What are they doing right? What could they be doing better? How do you use CFD or CFM to determine the goodness of mixing? What can a good CFD tool, especially made for mixing, reveal in the fluid mixing world? (Courtesy of Post Mixing.)

Compact Heat Exchanger Elements. Helically-finned tubes are often used to enhance heat transfer in compact heat exchangers. Complex flow phenomena are observed, which are attributed to the interaction between the geometry and turbulence conditions. A Ph.D. research study is conducted to analyze the effect of fin shapes and turbulence models. AcuSolve is used to predict both turbulent fluid flow and heat transfer. (Courtesy of SCOREC.)

Brick/Tet Element Comparison. It is indisputable that for a complex industrial geometry in 3D it is significantly easier to generate an unstructured tet mesh than unstructured or structured all hex mesh. What may be disputable is the CFD solution on these meshes. AcuSolve's unique finite element technology consistently delivers solutions that are equivalent in accuracy, but at lower computer resources for tet meshes.

Isentropic and Ideal Gas Density Relationships. AcuSolve^TM has been shown to be useful in solving mildly compressible flows with variable density. A converging-diverging nozzle shows good comparison with published theoretical results.

Turbulent Particle Tracking. In many flow problems, Reynolds Averaged Navier-Stokes (RANS) equations produce steady solutions. Particle tracing of these solutions, however, just accounts for diffusion due to the inherent unsteady nature of turbulence.

Tollmien-Schlicting Wave Propagation. In the second stage of laminar-turbulent boundary layer transition, unstable disturbances in the boundary layer appear as two-dimensional Tollmien-Schlicting (TS) waves. Since the growth rate of TS waves is well predicted by linear stability theory, their simulation provides a rigorous test problem for AcuSolve^TM.

Offshore Platform Hydrodynamics. Floating platforms are subjected to cyclic loads caused by wind, waves and currents. The motion of platforms and the resultant loads can be predicted with increased accuracy using CFD techniques. New methods are being developed to solve these difficult design problems. (Courtesy of Redwing Engineering.)