Advanced propfan analysis for the family of commuter airplanes

Advanced propfans were selected to be used throughout the family of commuters. These propulsion systems offer a 25 to 28 percent fuel savings over comparably sized turbofans operating in the 1990s. A brief study of the propulsion systems available for the family of commuters is provided and the selection of the advanced turboprops justified. The propeller and engine designs and performance are discussed. The integration of these designs are examined. Also addressed is the noise considerations and constraints due to propfan installation

Small Engine Component Technology (SECT) studies

A study was conducted to identify component technology requirements for small, expendable gas turbine engines that would result in substantial improvements in performance and cost by the year 2000. A subsonic, 2600 nautical mile (4815 km) strategic cruise missile mission was selected for study. A baseline (state-of-the-art) engine and missile configuration were defined to evaluate the advanced technology engines. Two advanced technology engines were configured and evaluated using advanced component efficiencies and ceramic composite materials; a 22:1 overall pressure ratio, 3.85 bypass ratio twin-spool turbofan; and an 8:1 overall pressure, 3.66 bypass ratio, single-spool recuperated turbofan with 0.85 recuperator effectiveness. Results of mission analysis indicated a reduction in fuel burn of 38 and 47 percent compared to the baseline engine when using the advanced turbofan and recuperated turbofan, respectively. While use of either advanced engine resulted in approximately a 25 percent reduction in missile size, the unit life cycle (LCC) cost reduction of 56 percent for the advanced turbofan relative to the baseline engine gave it a decisive advantage over the recuperated turbofan with 47 percent LCC reduction. An additional range improvement of 10 percent results when using a 56 percent loaded carbon slurry fuel with either engine. These results can be realized only if significant progress is attained in the fields of solid lubricated bearings, small aerodynamic component performance, composite ceramic materials and integration of slurry fuels. A technology plan outlining prospective programs in these fields is presented

Space Transportation Materials and Structures Technology Workshop

The Space Transportation Materials and Structures Technology Workshop was held on September 23-26, 1991, in Newport News, Virginia. The workshop, sponsored by the NASA Office of Space Flight and the NASA Office of Aeronautics and Space Technology, was held to provide a forum for communication within the space materials and structures technology developer and user communities. Workshop participants were organized into a Vehicle Technology Requirements session and three working panels: Materials and Structures Technologies for Vehicle Systems, Propulsion Systems, and Entry Systems

Towards a Low-Carbon Future for Offshore Oil and Gas Industry A Smart Integrated Energy Management System with Floating Wind Turbines and Gas Turbines

Decarbonizing offshore oil and gas fields is crucial in the global fight against climate change. To achieve this objective, the offshore oil and gas industry has embraced innovative energy systems, including microgrids that seamlessly integrate renewable energy sources like floating wind turbines. This study presents a comprehensive investigation into an integrated energy management system for an offshore microgrid, encompassing three platforms and a floating wind farm, along with green hydrogen production and storage facilities. The operational decision-making process for such a complex microgrid, involving numerous assets, presents notable challenges. To address this, a sophisticated smart management system is employed, enabling efficient optimization with advanced forecasting capabilities to identify the most cost-effective and environmentally friendly version of the microgrid's operation. To overcome the intricacies of optimization and computational constraints, a novel hybrid optimization approach, with a platform-centric strategy, is utilized. Leveraging real-world operational data, the study harnesses an innovative online optimization method fortified with state-of-the-art AI algorithms. The results of the optimization are benchmarked against a rule-based operation, wherein no formal optimization occurs, but the most economically viable decisions are made. The findings underscore the effectiveness of the developed optimization method, leading to a significant 16% reduction in operational costs and carbon-based emissions compared to the rule-based approach. This study effectively demonstrates the real-world applicability of the developed method by applying and testing the smart management system on an actual offshore platform with minimal simplifications. The investigation provides valuable evidence of the method's adaptability to complex operational scenarios, highlighting its potential for practical implementation in the offshore oil and gas industry.publishedVersio

Issues in federally supported research on advanced automotive power systems

Based on research supported by Division of Policy Research and Analysis, National Science Foundation, under grant no. PRA-768101

Advanced superposition methods for high speed turbopump vibration analysis

The small, high pressure Mark 48 liquid hydrogen turbopump was analyzed and dynamically tested to determine the cause of high speed vibration at an operating speed of 92,400 rpm. This approaches the design point operating speed of 95,000 rpm. The initial dynamic analysis in the design stage and subsequent further analysis of the rotor only dynamics failed to predict the vibration characteristics found during testing. An advanced procedure for dynamics analysis was used in this investigation. The procedure involves developing accurate dynamic models of the rotor assembly and casing assembly by finite element analysis. The dynamically instrumented assemblies are independently rap tested to verify the analytical models. The verified models are then combined by modal superposition techniques to develop a completed turbopump model where dynamic characteristics are determined. The results of the dynamic testing and analysis obtained are presented and methods of moving the high speed vibration characteristics to speeds above the operating range are recommended. Recommendations for use of these advanced dynamic analysis procedures during initial design phases are given

QCSEE task 2: Engine and installation preliminary design

High-bypass turbofan engines with features required for commercial short haul powered lift transports were designed. Two engines were configured for each of the externally blown flap installations, under-the-wing and over-the-wing. Estimates of installed and uninstalled performance, noise, and weight were defined for each propulsion system