Coupled Analysis Capability of ANSYS Makes Virtual Prototyping Easier

You can read the advertorial published in the September 2019 Issue of MSI Turkish Defence Review here:

 

Represented in Turkey by NUMESYS, as an Elite Channel Partner, ANSYS software can perform many analyses needed in virtual prototyping, especially in such fields as mechanical, thermal, fluid, electromagnetic and optical engineering, from a single platform through its broad range of modules. The results garnered from the coupled solutions offered by ANSYS through these different analysis methods can be evaluated together, making the virtual prototyping processes much more effective.

Virtual prototyping, which provides that at the current technology level achieved, the real-world performance of the product can be observed in a digital environment, offering many advantages. So, what led us to enter the field of virtual prototyping?

• The ability to improve product performance through parametric studies and optimization algorithms performed in the digital world, prior to creating a physical prototype;
• The ability to test performance in all operational situations that may occur, and in extreme conditions and scenarios;
• The ability to increase the reliability of the final product; and
• The ability to report on performance criteria without the need of extensive experimental studies.

All of these advantages shorten the time needed to launch the product on the market, provide savings in the budget allocated for R&D, offer advantages in global competitions and improve the quality of the first physical prototype.

Man-made products are required to operate in different conditions. In the real world, many different physical factors are intrinsically combined, and multi-physics principles apply. The performance of a product is affected by the fluids it requires to operate and by its mechanical structure, as well as electromagnetic, optical, thermal and acoustic factors. Accordingly, a vital need emerges to make accurate simulations involving a virtual prototype under the influence of significant physical forces and the interactions between these forces. At this point, multi-physics simulations come into the game. In fact, these methods, as the most important aspect of virtual prototyping, provide a better understanding of product performance by considering the interactions of multiple engineering disciplines.

In general, there are three components to multi-physics solutions:

• Data transfer: Transferring and matching data from experiments, other software packages and in-house simulation tools, for inputs of the first condition or boundary condition.
• One-way connection: Making an automatic result transfer when one physical solution is dependent on another.
• Two-way connection: Making a two-way integration where different physical solutions interact with each other.

Regardless of the fact that the need for simulation requires whichever of the above cases, ANSYS can draw upon a wide range of multidisciplinary solutions from within the product family, as well as the flow charts used to couple these solutions.

 

In general, engineering problems in the present day require an interdisciplinary approach, and it is becoming increasingly difficult to analyse the data obtained from different software and to come up with a result. In such situations, ANSYS, which allows different solutions to be used within the same graphical interface and permits both one-way and two-way connections to be made, stands out as a platform that can draw upon various methods of analysis. Among the various interdisciplinary multi-physics studies that can be carried out through ANSYS are:

• fluid structure interactions (FSI);
• thermal and mechanical (thermomechanical) analyses;
• noise/vibration/hardness (NVH) applications for electric motors;
• reviews of thermal and mechanical effects on chips, packages and electronic boards;
• electromagnetic, electrothermal, electromechanical effects and electromagnetic cooling of electrical equipment; and
• effects of thermal deformation on lighting performance in lighting products.

 

Thermal Deformation and Optical Performance of Headlights

The ability of different modules of ANSYS to respond to different physics and engineering problems can be explained through the example of temperature management in headlights. The temperature management of headlights is important for manufacturers and suppliers in terms of compliance with the ever-improving safety standards, which are becoming more difficult to achieve. The heat given off by headlights causes thermal expansion and deformation, resulting in changes in the direction of light.

The Icepak, Fluent, Mechanical and SPEOS modules of ANSYS allow the thermal performance, the final deformation and the optical performance of a headlight to be simulated to ensure compliance with the requirements.

The workflow to identify a solution to the multi-physics problem regarding the “Effects of thermal deformation of headlight components on light performance” can be summarized as follows:

• Simulation of the optical system through ANSYS SPEOS when deformations are not taken into account.
• Solar energy striking the headlight system causes obliqueness and colorimetric changes in the optical system. To analyse this, lighting maps simulating solar loads at different times of the day are generated by the ANSYS SPEOS.
• The thermal conductivity of the PCB over the heat capacity is generated by the ANSYS Icepak.
• These two inputs are then used by the ANSYS Fluent module to analyse the combined heat transfer.
• ANSYS Mechanical makes a steady state thermal analysis, and the results of this analysis and the thermal deformations are calculated.
• The modified and distorted headlight system is simulated again with the ANSYS SPEOS to compare the differences.

Comparison of the lighting performance of the headlight before (left) and after (right) thermal deformation, through ANSYS SPEOS.

 

 

Increasing the Life Cycle and Performance of PCBs

Another example of a multi-physics application is the thermal analysis of electronic boards (PCBs). Aside from performance, the compatibility of electronic boards with the environmental conditions is of great importance in practice. Normally, almost all electronic boards are housed in casings to protect the PCB from dust, moisture and vibration. However, this requirement brings with it thermal problems. ANSYS software can simulate the thermal behaviour of an electronic board within the case, along with such elements as fans and thermal absorbers used for cooling purposes, and can simulate the expansion and deformation of the electronic board with reference to the resulting temperature distribution. To obtain more realistic results during multi-physics simulations of electronic boards, the PCB must first be electromagnetically analysed to provide inputs for thermal simulations.

Simulations of electronic boards involve many other factors, such as resonance modes, near/far-field radiation problems, power/signal integrity and EMI/EMC. An example of an electrothermal simulation will be given here.

• A current and power map of the PCB can be calculated using the ANSYS SIWave and HFSS 3D Layout software, considering the integrated circuit elements that separately emit heat within the PCB, through a DC/IR analysis.
• After using the power map as an input for the ANSYS Icepak software, the temperature distribution on the PCB can be analysed.

 

• Thermal deformations due to temperature distribution can be analysed using ANSYS Mechanical software based on the data obtained from the ANSYS Icepak

 

• After checking the final temperature distribution, the analysis of the performance of the fan and the heat-absorbing elements in cooling the electronic board within the case can be continued using the ANSYS Icepak

 

• One of the most important performance criteria in electronic boards is the strength of the board. ANSYS Sherlock software can determine the mechanical life of all components of the electronic board under vibration loads, separately.

 

 

The importance of resolving such complex engineering problems through virtual prototyping and multi-physics simulation is increasing every day, according to which, the software investments of engineering companies are shifting towards multi-physics solutions. This increases their engineering capabilities, while also resulting in reducing the costs associated with prototypes that do not operate properly.