Why do we use CFD Simulation in Additive Manufacturing? Flow Science told us and will showcase it at Formnext 2022

Our means of transport (car, train, plane, etc.) or household appliances are a few examples of everyday products that may require the use of computational fluid dynamics (CFD) in the product development process.

CFD is a branch of fluid mechanics that focuses on numerical analysis of complex fluid flows. Used in a wide range of industries, from aerospace to biotech to civil engineering, CFD has gained recognition as an emerging technology around the world. Since the 2000s, the market has witnessed a significant increase in the development and application of CFD to all areas related to fluid behavior associated with momentum, heat, and mass transfer. However, the potential for such solutions in the AM industry has yet to be fully realized.

One company that has brought the development of CFD solutions to AM is Flow Science, a software company that has over 40 years of experience in modelling free surface flows. Known for a wide range of solutions used for various manufacturing processes across industries, the company’s extensive portfolio includes FLOW-3D AM, a CFD software engineered to address the physical complexity of additive manufacturing processes.

How CFD fits into the AM ecosystem

As explained earlier, CFD involves studying fluid flow using numerical methods. These numerical methods require computers to solve complex equations and determine analytical solutions that will enable the simulation of fluid interaction in different environments. Various situations can benefit from the use of a simulation software: the need to create and simulate models at low cost before investing in hardware prototypes; the need to test several designs quickly and efficiently before choosing one to build on an additive manufacturing system, or even the need to test the integration of the full design by connecting the simulation software to hardware; all of which can be achieved through the use of a dedicated technology called digital twin that CFD helps to create.

As seen in a recent dossier dedicated to this topic, the DT concept goes beyond what may happen to a physical product, to encompass the prediction of production and performance within specific environments. FLOW-3D AM is therefore a solution in virtual representation of additive manufacturing processes that aims to achieve accurate and robust flow simulations of AM systems.

From material extrusion to binder jetting, directed energy deposition, and laser powder bed fusion, FLOW-3D AM can be used to analyze, in detail, the flow patterns of the process material. The software accounts for physical phenomena such as the recoil pressure, surface tension, thermal plume, powder interactions during settling and spreading, non-Newtonian rheology, viscoelasticity, thermal shrinkage, and many others. Our customers use FLOW-3D AM to understand the source of the defects in the process, select optimal parameters, assess the feasibility of new printing materials, and to improve the design of their machines”, Dr. Marcin Serdeczny, CFD Engineer at Flow Science told 3D ADEPT Media.

This means that there are several aspects of AM processes that one can better understand or optimize through CFD simulations. In a Laser Powder Bed Fusion (LPBF) process for instance, where powder is spread onto a build plate and a laser beam then melts and fuses the powder, the engineer can perform CFD simulations of the melt pool to obtain an input for modelling the laser beam’s interaction with the powder bed and melt pool formation that will follow. However, it should be noted that to do so, he should perform a discrete element method (DEM) simulation upfront to simulate the powder spreading process in detail. Such simulation method accounts for particle dynamics, particle collisions and geometry effects.

This is just one example that illustrates the potential of CFD for an AM process. Flow Science plans to unveil other examples of insights that its customers achieve with FLOW-3D AM. “We have many case studies for different AM processes that our staff will be happy to discuss in detail. We will be available to demonstrate FLOW-3D AM, FLOW-3D POST, and FLOW-3D (x), as well as discuss the licensing options we have for commercial users, research institutions and academics,” Serdeczny states.

Flow Science’s 2022 AM roadmap and what we can expect moving forward

As seen in the industry, the upgrade and development of software solutions is core to any software company’s activities. Flow Science is no exception. The company releases a new version of FLOW-3D twice a year, with new and enhanced physical models, as well as improvements to the graphical user interface based on user feedback. In this vein, the latest version of FLOW-3D AM came with several new features such as an enhanced user interface and a thermal plume model that accounts for energy losses due to laser scattering above the melt pool.

In addition to FLOW-3D AM, earlier this year we released a new version of FLOW-3D POST – our advanced post-processing tool, which allows for intuitive and sophisticated visualization and analysis of our CFD results. In this new version, we introduced macros and batch post-processing capabilities that allow our users to automate and speed up their work. We have just released a second version of our new product FLOW-3D (x), an optimization and automation software that connects with FLOW-3D AM, FLOW-3D POST, as well as other commonly used engineering software to create a unified workflow. FLOW-3D (x) uses artificial intelligence and was specifically designed to work with computationally heavy problems such as CFD simulations. The software automatically chooses the optimization strategy based on the time the user has to finish the project. Additionally, FLOW-3D (x) allows seamlessly run parametric sweeps or preforms numerical Design of Experiment (DoE). In this latest release, we have extended the optimization engine to benefit from running multiple simulations in parallel with the ability to run on remote hardware”, Serdeczny outlines.

From a business standpoint, we can legitimately say the first three quarters of the year have been successful for the company that has not only welcomed new users but has also hired skilled engineers with doctoral degrees in additive manufacturing to better assist customers in this field.

Moving forward, 2023 will see further development of FLOW-3D AM with a key focus on LPBF and DED. “Our next development is focused on improving the discrete element method to increase the accuracy of the powder behavior and spatter prediction. Moreover, we look at modelling other AM processes such as Wire-Arc, for which we have already introduced a simplified model that will be further developed. We will continue our work making sure that the graphical user interface provides an efficient and intuitive workflow that is easy to use for non-CFD experts. And we have our yearly planned releases of FLOW-3D POST and FLOW-3D (x) that will bring new features and improvements”, Flow Science explains.

In the meantime, visitors at Formnext can interact with the Flow Science team and discover their products in Hall 12.0, B75. You can also listen to Dr. Marcin Serdeczny who will discuss “Next generation melt pool control via multi-laser beam shaping in Laser Powder Bed Fusion” at Introducing Stage at Formnext @ TCT on Wednesday, November, 16 at 10:20 am CET. Serdeczny’s presentation will highlight findings and key takeaways from a project achieved in collaboration with nLIGHT, Inc., a leader in the development of semiconductor and fiber lasers. Another talk on the topic will be given at the 2nd nLIGHT AFX360° forum (time and date to be confirmed).

Corporate communication and marketing expert by training at 3D Adept, Kety is currently leading the publication’s editorial and content activities. She has a unique gift for knowing how to grab an audience's attention on insights that matter – in this case, everything related to additive manufacturing. She believes that a wide range of innovations still have to be discovered about the technologies that shape the world of tomorrow and she has made it her objective at 3D ADEPT Media.