Abstract: In accordance with one aspect of the present invention, a combustor is disclosed having three separate domes, each dome having disposed therein a plurality of circumferentially spaced mixers for uniformly mixing air and fuel. The combustor utilizes a high percentage of the total available combustion air at the dome area in order to maintain a lean mixture of air and fuel during all levels of engine output. Besides providing an unobstructed area in the diffuser dump region upstream of the mixers for the combustion air, sealing means is included to prevent cooling air from entering the combustion chamber until downstream of the primary combustion zone. Heat shields having radial centerbodies are also included between each dome to isolate each primary combustion zone.

Abstract: The cooling air duct for a clearance control system has spacers which abut the surface to be cooled. Critical spacing for proper cooling is obtained and is easily inspected. Ajustable supports facilitate adjustment.

Abstract: An instrument for carrying out mechanical strain tests on metallic samples with the addition of an electrical system for varying the temperature with strain, the instrument including opposing arms and associated equipment for holding a sample and varying the mechanical strain on the sample through a plurality of cycles of increasing and decreasing strain within predetermined limits, circuitry for producing an output signal representative of the strain during the tests, apparatus including a set point and a coil about the sample for providing a controlled temperature in the sample, and circuitry interconnected between the strain output signal and set point for varying the temperature of the sample linearly with strain during the tests.