An Exact Solution for Heat Transfer of a Jet Co-Axially Impinging on a Rotating Disk and Its Comparisons with Stagnation Point Experiments

IntroductionJet impingement is a widely used high-efficiencytechnique fOr cooling rotating disks, which are end-wallsurfaces of gas turbine rotors, comPuter disk drives etc.Fluid f'low, heat trallsfer and geometric arrangement inthe case of a single round jet impinging co-axially in anorthogonal mode on a rotatng disk are characterized byFig. l.Many peculiarihes of fluid fIow and heat transfer ofreal impinging jets under comPlicated conditions(different system geometry, impinging flow proper…

An exact solution for heat transfer of a jet co-axially impinging on a rotating disk and its comparisons with stagnation point experiments

An exact solution of laminar heat transfer problem for a uniform flow perpendicular to a rotating disk was obtained. Radial velocity at the outer edge of the boundary layer increases linearly in the radial direction, while the temperature difference between the disk and outer flow follows a power law. The problem is solved using self-similar velocity and temperature profiles. Nusselt numbers were computed for the Prandtl numbers Pr=1 and 0.71 at different values of parameters affecting flow and heat transfer. Special flow regime was identified where rotating disk heat transfer is determined only by peculiarities of the impinging flow. Results of predictions agree well with known experiments in the vicinity of the stagnation point.