A combined CFD and network approach for a simulated turbine blade cooling system

摘要

A combined computational fluid dynamics (CFD) and network analysis is proposed as an approach to solve complex flow and heat transfer problems. Perforated cylindrical passages with impingement and film cooling arrangement in a circular cylinder are considered as an example for demonstrating the methodology and simulated a cooled turbine blade geometry. Two networks namely, flow and thermal networks are developed. CFD calculations are performed to estimate loss factors and thermal resistances, which are used as input to the flow and thermal networks. Iterative procedures are adopted for solving the networks. Results of the pressure and temperature at different nodes, flow rates through the elements and film hole effectiveness in the span-wise and peripheral directions are presented at selected positions for different pressure inlet conditions of coolant. The results indicate that 0.15 percent increase in coolant to mainstream flow ratio causes 20 percent reduction in coolant outlet temperature and 25 percent increment in film cooling effectiveness.