MATERIALE PLASTICE ♦ 56 ♦ no. 4 ♦ 2019 910 http://www.revmaterialeplastice.ro Aspects Regarding the Use of 3D Printing Technology and Composite Materials for Testing and Manufacturing Vertical Axis Wind Turbines ALEXANDRU-POLIFRON CHIRIȚĂ 1 *, PAUL-PETRU BERE 2 , RADU IULIAN RĂDOI 1 , LILIANA DUMITRESCU 1 1 Hydraulics and Pneumatics Research Institute INOE 2000-IHP, 14 Cuțitul de Argint Str., 040558, Bucharest, Romania 2 Technical University of Cluj-Napoca, 28 Memorandum Str., 400114, Cluj-Napoca, Romania The article presents the technology and process, whereby a small-scale demonstration model and the real-scale prototype of vertical axis wind turbine blades are produced using rapid prototyping technology (3DP) and GFRP surface coatings, which help to improve the mechanical properties. In the end of the article the results of the production process and the advantages of combining these technologies are presented. Keywords: vertical axis wind turbine, 3D printing, polylactide, GFRP. 3D printing (3DP), specifically fused filament fabrication (FFF), is one of the most accessible and widespread rapid prototyping technologies [1-7]. Recent advances in additive manufacturing (AM), a construction technique where a three-dimensional object is created through the build-up of thin layers of a thermoplastic material, have resulted in the commercialization and popularization of what is commonly known as 3DP. [1-4, 6-8] Objects for 3D printing are stored in digital files for modification using 3D modeling software, and are easily copied, and transferred via the Internet. Small wind turbine technology stands to benefit greatly from this technology. With the appropriate design, wind turbines could be rapidly manufactured (printed) and assembled on-site at an as needed basis without too many tools beyond a 3D printing machine and printing filament, or at least it helps a lot in creating the complicated geometry of wind turbine blades that would be quite difficult to produce with other technologies. Applications for wind energy technology The primary and historic application of 3D printing technology for wind turbines has been through rapid prototyping – where a model of a part for industrial manufacture is produced through the 3D printing process so that engineers and designers can test certain component properties within a controlled environment before releasing a design into full production. Typically scale models of larger components are printed. 3DP, rapid prototyping has been utilized in the sustainability technology sector to produce aerodynamic research models hydro turbine prototypes [3, 4, 9] and recently micro-scale wind turbines. In each of these cases the printed parts were prototypes simulating the construction and shape of the manufacture-able part in different materials and construction means. With the emergence of affordable and accessible 3DP technology there is the opportunity for wind energy to realize a second, and potentially equally impactful, benefit. By considering the approach of designing small wind turbines as a modular assembly of components for direct manufacture by a consumer level 3D printer, new opportunities are presented for decreasing cost, reducing waste and increasing accessibility for wind turbines around the world [10-14]. This approach extends beyond rapid prototyping and into rapid manufacturing, defined as the direct production of finished goods from a rapid prototyping device [15-20]. Experimental part Materials and methods This section presents the production process of a functional model (demonstrator) in 1:5 scale, as well as the production process of the Darrieus blades of the experimental model in 1:1 scale. They are shown in Figure 1. * chirita.ihp@fluidas.ro, Phone: 0769.404.303