Interview 1


Interviewee profile: University, representative of WP5
Tags used: application – investigations – benefits.


Head of Meadow Aerodynamics laboratory at Tel Aviv University (TAU), Israel

Q1: Tel Aviv University has recently purchased a 3D prototyping machine. Could you please tell us howyou envisage exploiting the machine’s potential within AFLoNext? What was your motivation and what is the planned application?

A1: TAU is actually in the possession of more than one 3D printer. We have a range of machines one made by Stratasys (formerly the Israeli company Objet) which has a range of materials and a resolution of about 0.1mm, and a few simpler machines with poorer resolution of about 0.5mm. The machines differ in the print time, the finalization process, the surface quality and certainly by the material cost. The main benefit of the 3D printing machines is the capability to make complex parts that would be extremely complex, time consuming and costly to fabricate otherwise.

In the images below you can see parts made for adapting the TAU developed suction and pulsed blowing actuator to fit inside an existing aerofoil that was used previously for separation control studies. Another picture shows the upper surface of the airfoil with an array of SaOB actuators housed under the surface, and the suction holes and pulsed blowing slots clearly visible. Making these parts from conventional machining would have cost 10 times more and last at least 10 times longer. The student working on this project, Dima Sarkorov designed all these parts using a CAD software package and downloaded an STL file directly to the machine which gave Mr. Sarkorov great flexibility in designing complex shapes.

Q2: At what stage of the project will the machine contribute to the AFLoNext investigations?

A2: The machines already contribute significantly to the progress of two tasks, as part of WP 2 and WP 5, TAU is involved in. In WP5, for instance, the student working on the project, Danny Dolgopyat, in the effort to miniaturize his version of the SaOB actuator to fit into the thin trailing edge region of an aerofoil, printed several versions. Eventually we reached the conclusion that we have to resort back to conventional CNC milling since details smaller than 0.1mm were needed. So one does not need to expect 3D will replace conventional milling techniques, though it is a great prototyping tool. Therefore, the nozzles, connection and cover parts to the small SaOB system probably will be made in the 3D printer technology. This can be shown in the example below, where we have “printed” an early version of a slat intended to be used in AFLoNext.

Q3: What are the expected benefits of using a 3D approach within AFLoNext?

A3: The expected benefits are the ability to make very complicated shapes in significant short time and cost savings and therefore the capability to reach the project goals with higher certainty, and I might say with less anxiety.