In years past, research activities of most engineering organizations—both academic and industrial—focused on one or more aspects of design, fabrication, and experimentation. As a young engineer in a large applied research laboratory, I remember reviewing a flowchart of our department’s design method and realizing that there was no termination point! Indeed, it seemed that our organization was caught in a perpetual loop, relegated to incremental advances in our understanding of the relevant technologies with little opportunities for significant creativity. True, we had a sound reputation for our expertise in design and testing, but we needed to jump confidently from evolutionary, empirical developments to revolutionary new concepts. While computational analysis tools have existed for a while, only within the last decade have the results been sufficiently accurate and timely to influence design. Now, engineers can think more confidently beyond the usual, incremental technology improvements and more affordably evaluate their creative ideas without undue risk or an abundance of costly design, build, and test cycles.
For the business of designing process heat exchangers, computational fluid dynamics (CFD) tools are still not practical for everyday use. However, in a research consortium such as HTRI, integrating advanced analysis tools like CFD with industrial-sized experimentation and then applying them to real-world technical problems provides a significant synergistic benefit to the consortium members. For example, we have used CFD analyses successfully to
• Improve the quality and extend the performance of our experiments
• Study the behavior of empirically-based correlations beyond the limits of available data or achievable temperatures and pressures
• Set priorities for developing correlation models by identifying which physical phenomena are most important
• Diagnose and understand problems in operating shell-and-tube heat exchangers
• Determine crossflow velocity profiles for assessing tube vibration potential
Moreover, we have used our experimental results, as well as field data from our consortium members, to validate detailed computational analyses. In the future, we plan to use optical imaging to extend the scope and resolution of our measurements. Finally, knowing the current technical challenges of our consortium members helps to focus our computational resources on those areas that will provide the most benefit. Certainly CFD and finite element analysis tools are valuable in their own right as the many trade journal advertisements suggest, but they become particularly beneficial when carefully validated and applied to real-world problems in the context of a focused research program.
