NUMERICAL PREDICTIONS OF PRESSURE DROP AND HEAT TRANSFER IN A BLADE INTERNAL COOLING PASSAGE WITH CONTINUOUS/TRUNCATED RIBS

Abstract

Ribs are often used in the mid-section of internal turbine blades to augment heat transfer from the blade wall to a coolant, but most research works are concerned only with continuous ribs attached to the side walls. In this paper, a turbulent flow and heat transfer of a rectangular passage with continuous and truncated ribs on opposite walls have been predicted numerically. Two types of ribs are studied: 90-deg ribs and 45-deg V-shaped ribs. The inlet Reynolds numbers range from 12,000 to 60,000. The complex three-dimensional turbulent flows inside the blade internal coolant passage and heat transfer between the rib-walls and side-walls are presented. The overall performances of six different ribbed passages are evaluated and compared. Numerical results show that the passage with truncated V-shaped ribs is very effective in improving the heat transfer performance with a low pressure drop. (Less)