Affiliation:
1. School of Mechanical Engineering, University of Bath, Bath, United Kingdom
Abstract
Conditions in the internal-air system of a high-pressure turbine stage are modeled using a rig comprising an outer preswirl chamber separated by a seal from an inner rotor-stator system. Preswirl nozzles in the stator supply the “blade-cooling” air, which leaves the system via holes in the rotor, and disk-cooling air enters at the center of the system and leaves through clearances in the peripheral seals. The experimental rig is instrumented with thermocouples, fluxmeters, pitot tubes, and pressure taps, enabling temperatures, heat fluxes, velocities, and pressures to be measured at a number of radial locations. For rotational Reynolds numbers of Reφ ≃ 1.2 × 106, the swirl ratio and the ratios of disk-cooling and blade-cooling flow rates are chosen to be representative of those found inside gas turbines. Measured radial distributions of velocity, temperature, and Nusselt number are compared with computations obtained from an axisymmetric elliptic solver, featuring a low-Reynolds-number k–ε turbulence model. For the inner rotor-stator system, the computed core temperatures and velocities are in good agreement with measured values, but the Nusselt numbers are underpredicted. For the outer preswirl chamber, it was possible to make comparisons between the measured and computed values for cooling-air temperatures but not for the Nusselt numbers. As expected, the temperature of the blade-cooling air decreases as the inlet swirl ratio increases, but the computed air temperatures are significantly lower than the measured ones. Overall, the results give valuable insight into some of the heat transfer characteristics of this complex system.
Reference22 articles.
1. Bunker
R. S.
, MetzgerD. E., and WittigS., 1992a, “Local Heat Transfer in Turbine Disk Cavities. Part I: Rotor and Stator Cooling With Hub Injection of Coolant,” ASME JOURNAL OF TURBOMACHINERY, Vol. 114, pp. 211–220.
2. Bunker
R. S.
, MetzgerD. E., and WittigS., 1992b, “Local Heat Transfer in Turbine Disk Cavities. Part II: Rotor Cooling With Radial Injection of Coolant,” ASME JOURNAL OF TURBOMACHINERY, Vol. 114, pp. 221–228.
3. Chen
J.-X.
, GanX., and OwenJ. M., 1996, “Heat Transfer in an Air-Cooled Rotor–Stator System,” ASME JOURNAL OF TURBOMACHINERY, Vol. 118, pp. 444–451.
4. Chen, J.-X., Owen, J. M., and Wilson, M., 1993a, “Parallel-Computing Techniques Applied to Rotor–Stator Systems: Fluid Dynamics Computations,” Proc. 8th Intl. Conf. Numer. Meth. Laminar Turbulent Flow, Swansea, Pineridge Press, pp. 899–911.
5. Chen, J.-X., Owen, J. M., and Wilson, M., 1993b, “Parallel-Computing Techniques Applied to Rotor–Stator Systems: Thermal Computations,” Proc. 8th Int. Conf. Numer. Meth. Thermal Problems, Swansea, Pineridge Press, pp. 1212–1226.
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