ͳ Aero‐thermal investigation of a multi‐splitter axial turbine J.P. Solano*, V. Pinilla ͳ , G. Paniagua, S. Lavagnoli, T. Yasa von Karman )nstitute for Fluid Dynamics, Turbomachinery and Propulsion Department, Chaussée de Waterloo, ͹ʹ, Bͳ͸ͶͲ Rhode‐Saint‐Genèse, Belgium Abstract This paper reports the external convective heat transfer in an innovative low‐ pressure vane, designed with a multi‐splitter configuration. Three aerodynamic airfoils are positioned in between larger structural vanes, replacing struts presently used in current aero‐engines, which results in superior aerodynamic performance. Static pressure and heat flux measurements were carried out in the large compression tube facility of the von Karman )nstitute, using pneumatic taps and single‐layered thin film gauges respectively. The steady and unsteady heat transfer distributions were obtained at representative conditions of modern aero‐ engines, with M ʹ,is close to unity and a Reynolds number of approximately ͳͲ ͸ . This facility is specially suited to control the gas‐to‐wall temperature ratio that drives transition mechanisms. The heat transfer across the multi‐splittered passages is confronted with correlations on ducts to further characterize the boundary layer status. The data will be used to guide code developers by verifying their boundary layer transition models, and designers by showing the areas of the vane where heat transfer is most sensitive to the off‐design conditions. Keywords: transition, thin film gauges, turbine, convective heat transfer * Corresponding author. Present address: Dep. )ngeniería Térmica y de Fluidos, Universidad Politécnica de Cartagena, Campus Muralla del Mar, ͵ͲʹͲʹ Cartagena, Spain. Tel: +͵Ͷ ͻ͸ͺ ͵ʹͷͻ͵ͺ, Fax: +͵Ͷ ͻ͸ͺ ͵ʹͷͻͻͻ. Email address: juanp.solano@upct.es ȋJ.P. SolanoȌ ͳ Present address: )ndustria de Turbopropulsores S.A., Parque Tecnológico de Zamudio, Edificio ͵ͲͲ, Ͷͺͳ͹Ͳ Zamudio, Spain