Effects of the 1-0-1 Structure Arrangement on the Cooling Effectiveness of Double-Wall Blade Suction Side with High Rotational Speeds

The double-wall impingement/effusion cooling structure represents a novel and efficient design scheme for turbine blades of engine. For turbine rotor double-wall blades, rotation alters flow and heat transfer characteristics, leading to localized high-temperature zones on the suction side of blade when cooling air is limited and film coverage is insufficient. However, there is a scarcity of existing research concerning typical double-wall cooling structures at high rotational speeds. Therefore, this research investigates the influence of the arrangement of the 1-0-1 cooling structure on the film cooling effectiveness of double-wall blade suction sides at the high rotational speeds (5000–15000 rpm). The heat transfer and flow characteristics of twelve different cooling structures, with four different 1-0-1 cooling structures arranged in each of the three areas along the flow direction of the suction side, were studied by simulation of fluid-solid conjugate heat transfer. Results show that the rotational speed exerts a more pronounced impact on the film cooling effectiveness near the leading edge of the suction side compared to other regions on the same side. At rotational speeds of 5000–15000 rpm, apart from the high-radius region (over 50% of the blade height) near the leading edge at 5000 rpm, arranging the film holes upstream of the impingement holes reduces consumption of cooling air and improves film cooling effectiveness, due to the interaction influence of the rotation with the fluid pressure distribution, yielding an increase in film cooling effectiveness of up to 20.3%.