The Set-Based Concept approach (SBC approach) is a unique methodology, which allows a computer-based search of the design space with the aim to support concept selection. According to this approach, the search is simultaneously done at two levels including the conceptual solution level and the particular solution level. The main advantage of the SBC approach is that it permits concept selection to be based not just on one performance vector per concept, but rather on a set of performance vectors (per concept). This enables comparing concepts based not just on optimality but also on the inherent solution variability of the concept. In this study we employ a relaxed-Pareto approach to filter-out non-promising concepts during the search. This approach is based on the understanding that it is important to find not just concepts with performances in the combined Pareto-front (of all the concepts), but also within the vicinity of that front. In this study we demonstrate the applicability of the approach on a real-life design problem. We define several types of concepts of propellers, and simultaneously search the design space with many concepts and two design objectives. For this purpose we use a simulation model that has been developed at the Israel Aircraft Industry. It is shown that the approach may not just confirm the knowledge of an experienced propellers` designer, but it can help enhancing such knowledge. Furthermore, the proposed exploration technique can support novice engineers in developing a reliable perception of the design space.
