Available information concerning spot welding as a means of joining aluminum-alloy parts has been summarized and comparisons have been made of the relative merits of spot-welding and riveted aluminum-alloy structural elements. The results indicated that spot welding was as satisfactory as riveting insofar as resistance to static loads is concerned. Spot welds showed slightly lower resistance to impact loads but definitely lower resistance to repeated loads than rivets.

Analytical expressions are derived to show the geometric, thermodynamic, and aerodynamic relations among compressor, turbine, and exhaust nozzle for a gas-turbine engine. For a known compressor performance map, a matching method is described to show some of the design compromises that must be made when the components are to be combined into a turbine-propeller engine. A method of predicting engine performance for a range of operating conditions from known component maps is presented. An illustrative example of the matching method and the performance analysis is presented, showing some of the practical limitations of engine operation.

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