Accession Number : ADA260941


Title :   Flow Control Of Low Heat Load Turbine Airfoils


Descriptive Note : Final rept. Jul 87-Feb 91,


Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE GAS TURBINE LAB


Personal Author(s) : Epstein, A H ; Guenette, G R ; Stone, T D ; Stentoe, W J


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a260941.pdf


Report Date : 28 Feb 1992


Pagination or Media Count : 312


Abstract : The goal of this work was to examine how the heat load to turbines may be reduced by aero- dynamic design. The effort consisted of three separate investigations: (1) determination of the effect of small grooves in the flow direction (riblets) on heat transfer, (2) an investigation of the role of inviscid flow aerodynamics on heat load, and (3) examination of the measurement technology required to assess heat transfer and aerodynamic performance in a short duration turbine test facility. For the first effort, a low turbulence, constant wall temperature wind tunnel was constructed with one wall containing riblets. Measurements indicated a maximum of 5% reduction in heat transfer and 7% in skin friction drag. In the second effort, an integral technique was developed to predict laminar flow heat transfer and drag losses for a two- dimensional airfoil. The integral method was incorporated into the ISES inverse design code and comparisons were made to existing calculational methods and experimental data. For the third effort, errors associated with heat transfer and aerodynamic performance measurements in short duration (isothermal) test facilities were found to be small but not negligible. It is shown that these errors can be estimated to sufficient accuracy so that data from short duration facilities will have equal or better accuracy than that from conventional turbine rigs.


Descriptors :   *HEAT TRANSFER , *BOUNDARY LAYER , TEST AND EVALUATION , CONTROL , MEASUREMENT , TEMPERATURE , EXPERIMENTAL DATA , DYNAMICS , AIRFOILS , DRAG , LOSSES , WORK , TURBINES , WALLS , ERRORS , CONSTANTS , REDUCTION , COOLING , AERODYNAMICS , SKIN FRICTION , WIND TUNNELS , TEST FACILITIES , DETERMINATION , LAMINAR FLOW , FRICTION , INVISCID FLOW , TURBULENCE , LAYERS , TWO DIMENSIONAL , COMPARISON , INTEGRALS , FACILITIES , ACCURACY


Subject Categories : Aerodynamics
      Mechanics
      Jet and Gas Turbine Engines


Distribution Statement : APPROVED FOR PUBLIC RELEASE