Research turbine for high temperature core engine application. 1: Cold-airoverall performance of solid scaled turbine

A solid, half-scale model of a 50.8-cm (20-in) research turbine designed for a high temperature core engine application was investigated over a range of speeds and pressure ratios. The results of this test are presented. The effect of rotor blade twist was also investigated. At the design equivalent speed and specific work output, the total efficiency of the turbine with untwisted rotor blades was 87.1 percent; at the same pressure ratio the efficiency of the turbine with twisted rotor blades was 88.0 percent

Effect of variable stator area on performance of a single-stage turbine suitable for air cooling. 1 - Stator overall performance with 130-percent design area

Effect of variable stator geometry on performance of air cooling turbin

Research turbine for high-temperature core engine application. 2: Effect of rotor tip clearance on overall performance

A 25.4-cm (10-in) tip diameter turbine was tested to determine the effect of rotor radial tip clearance on turbine overall performance. The test turbine was a half-scale model of a 50.8-cm-(20-in.-) diameter research turbine designed for high-temperature core engine application. The test turbine was fabricated with solid vanes and blades with no provision for cooling air and tested at much reduced inlet conditions. The tests were run at design speed over a range of pressure ratios for three different rotor clearances ranging from 2.3 to 6.7 percent of the annular blade passage height. The results obtained are compared to the results obtained with three other turbines of varying amounts of reaction

Cold-air investigation of a turbine for high temperature-engine application. 5: Two-stage turbine performance as affected by variable stator area

The stator areas of the design two-stage turbine were both decreased and increased by nominally 30 percent, and the performances of the two turbines are compared with that of the design stator area turbine. Turbine efficiency decreased with stator area changes. Closing the stator area resulted in the more severe efficiency loss. The decrease in efficiency for both turbines is attributable to rotor incidence, off-design blade-surface velocities, and adverse reaction changes across the blade rows

Cold-air experimental investigation of a turbine with blade trailing edge coolant ejection. 1: Single-stage turbine

Tests were made on a 0.762-meter-tip-diameter research turbine to determine the effect of blade coolant flow on its aerodynamic performance. Both stator and rotor blades had trailing-edge slots for coolant ejection. The turbine was tested over a range of speed and pressure ratio. High primary efficiencies, calculated on the basis of primary air only, were obtained. The efficiency attained was identical to that reported for the turbine from a previous investigation were only slotted stator blades where incorporated in the turbine and tested. And it also compares with results for the turbine with solid blading. Independently varying the rotor coolant flow showed that rotor cooling imposed a severe penalty on turbine efficiency. The thermodynamic efficiency, which accounts for the ideal energies of both blade coolant flows, decreased linearly with rotor coolant at a rate of about 0.7 percent per percent rotor coolant fraction

Design and cold-air test of single-stage uncooled turbine with high work output

A solid version of a 50.8 cm single stage core turbine designed for high temperature was tested in cold air over a range of speed and pressure ratio. Design equivalent specific work was 76.84 J/g at an engine turbine tip speed of 579.1 m/sec. At design speed and pressure ratio, the total efficiency of the turbine was 88.6 percent, which is 0.6 point lower than the design value of 89.2 percent. The corresponding mass flow was 4.0 percent greater than design

Effect of variable stator area on performance of a single-stage turbine suitable for air cooling. 6 - Turbine performance with 70-percent design stator area

Variable stator area effect on performance of single stage turbine suitable for air coolin