Computer Aided Conceptual Design, a Concept Study of Fast Hydraulic 2/2-Way seat Valves

In this paper a concept study of 2/2-way seat valves is presented, using a new developed software tool for conceptual design and some computer based methods for assessing model consistency, computational allowability, and model complexity. The conceptual design software helps the designer to declare his/her physical understanding and generates automatically a mathematical description of the model. It links together the graphical domain of sketches/drawings with the symbol domain for reflecting the physical effects and the domain of basic mathematical models for their quantification. It also calculates the constraint matrix from the mathematical model, which maps the functional requirements (FR) from the functional domain to the design parameter (DP) from the physical domain. According to Nam, P. Suh (1990), certain features of this map gives valuable information on the complexity of a design. The constraint matrix can be transformed into a bipartite graph. A bipartite graph is the companion to the constraint matrix and shows exactly the same information. Theses two models are basic principles of constraint theory, which is a powerful tool for evaluating mathematical model consistency and computational allowability. If a mathematical model is consistent and the computation is allowable, the model will be well-posed. Finding the best solution for a technical product is rather difficult. Model complexity gives the designer a tool for evaluating different well-posed mathematical models. To demonstrate this approach a comparative evaluation of three different principles of a 2/2-way seat valve is discussed. These principles are a 2/2-way cartridge valve, a 2/2-way check valve, which are state of the art and a new leakage free2/2-way ball valve with an integrated deformable disk.