The investigation described in the paper was concerned with the computer-aided integration of the different tasks relating to the design of a fluid coupling in a drive system for an auxiliary boiler feed pump in a nuclear power station. The coupling would only be used in the event of a breakdown in the main boiler feed-pump system. Throughout the study, interactive 2D draughting and 3D solid modelling were used in the development of efficient, economical and fast solutions to the many problems encountered in the designs. The study also addressed the structural integrity of the critical components and the dynamic response of the assembly using 3D finite-element analyses. This was followed by the development of cutter-location source files for the machining of the critical components. The work highlights the interactive and integrated nature of the design tasks. fluid coupling, design, interaction, integration, solid modelling, impeller, rotor, slip, drag torque, mean flow path, finite-element method, manutacturing
DESIGN METHODOLOGY
Engineering design has traditionally been accomplished on drawing boards, with the design being documented in the form of detailed engineering drawings. Effectively, mechanical design includes the drawing of the complete product, as well as its components and the subassemblies, tools and fixtures necessary for the manufacture of the product. Clearly, the design process relies entirely on an iterative approach, in the sense that each iteration provides an improvement in the product. The main difficulty with this iterative approach is that it is time-consuming, and many hours of attempts are required before a design project is completed. Today, a number of design-related tasks can be performed with the assistance of a computer. These tasks include the following activities:
β’ interactive computer graphics and modelling, β’ computer-aided design,