963 research outputs found
NASA broad-specification fuels combustion technology program: Status and description
The program presented is a contracted effort to evolve and demonstrate the technology required to utilize broad-specification fuels in current and next generation commercial Conventional Takeoff and Landing aircraft engines, and to verify this technology in full-scale engine tests in 1983. The program consists of three phases: Combustor Concept Screening, Combustor Optimization Testing, and Engine Verification Testing. The development and screening of the combustion system designs for the CF6-80 engine and the JT9D-7 engine, respectively, in high-pressure sector test rigs are reported
The NASA broad-specification fuels combustion technology program: An assessment of phase 1 test results
An assessment is made of the results of Phase 1 screening testing of current and advanced combustion system concepts using several broadened-properties fuels. The severity of each of several fuels-properties effects on combustor performance or liner life is discussed, as well as design techniques with the potential to offset these adverse effects. The selection of concepts to be pursued in Phase 2 refinement testing is described. This selection takes into account the relative costs and complexities of the concepts, the current outlook on pollutant emissions control, and practical operational problems
The NASA pollution-reduction technology program for small jet aircraft engines
Three advanced combustor concepts, designed for the AiResearch TFE 731-2 turbofan engine, were evaluated in screening tests. Goals for carbon monoxide and unburned hydrocarbons were met or closely approached with two of the concepts with relatively modest departures from conventional combustor design practices. A more advanced premixing/prevaporizing combustor, while appearing to have the potential for meeting the oxides of nitrogen goal as well, will require extensive development to make it a practical combustion system. Smoke numbers for the two combustor concepts were well within the EPA smoke standard. Phase 2, Combustor-Engine Compatibility Testing, which is in its early stages, and planned Phase 3, Combustor-Engine Demonstration Testing, are also described
Performance of an annual combustor designed for a low-cost turbojet engine
Performance tests were conducted on a combustor designed for use in a low-cost turbojet engine. Low-cost features included the use of very inexpensive simplex fuel nozzles and combustor liners of perforated sheet material. Combustion efficiencies at the altitude-cruise and sea-level design points were approximately 94 and 96 percent, respectively. The combustor isothermal total-pressure loss was 8.8 percent at the altitude-cruise-condition diffuser-inlet Mach number of 0.335. The combustor-exit temperature pattern factor was less than 0.3 at the altitude-cruise, sea-level-cruise, and sea-level-static design conditions. The combustor-exit average radial temperature profiles at all conditions were in very good agreement with the design profile. The intense mixing required because of the very high combustor heat-release rate had an adverse effect on ignition capability at altitude windmilling design conditions
Programme evaluation theory: the next step toward a synthesis of logic models and organisational theory
This paper argues that the formulation of policy, at whatever level, to whatever scale
or scope, is any different to the myriad of processes involved in strategic planning
within and between organisations, and the attendant decision making processes that
abound in such an environment (Hage, 1980; Hickson, 1987; Thompson, 1967;
Weick, 1976). Those forces that impact upon organisations are precisely the same
forces that impact upon policy making groups who are themselves ‘organisations’ (or
institutions), whether actual or representative. This provides a startign point for
considering a synthesis between various models or paradigms. The argument
continues, that program theory and the program logic model can incorporate and
synthesise theories from elsewhere that, in turn, usefully inform and develop
programme theory and program logic. A ‘hierarchical’ model is presented to explore
the linkages between the components and ‘simple’ processes of theory, programme
theory, logic modelling, organisational functioning, policy, and the consequent
impact. It is hoped that this model can be used as a framework to: (a) determine
which components are essential to give the policy external validity, credibility,
implementability, and so on; and (b) provide a common point of reference for policy
makers, stakeholders, and evaluators
Key principals of on-line tuition and learning for graduate students
A successful learning experience depends on, and requires, the same commitment and activities from students as in face-to-face learning. It is important to ensure you don’t fall behind with your work – the reading and the conference contributions. The forums provide interaction and the interaction is more than just discussion. It means actively taking part, keeping up to date, and collaborating
The issue of social construction in and through organizations texts: a case in point
This paper provides an attempt to: 1) bring some of the more quantitative approaches to the analysis of bodies of written text into the field of Organizational Discourse Analysis (ODA) without losing the important qualitative aspects; and 2) to re-extend the relationship between text and context. The point in relation to the theme of the conference is that this throws up examples of dramaturgical constructions of identity/ies-in-text that occur during mundane, routine activities (meetings)
A simple introduction to coaching in organizations and business
This unit provides you with a brief overview of the core principles, skills, and capabilities required for coaching. It is set in the context of organizations and businesses, but it is important to recognise that the core principles, skills and capabilities are universal.
The market for coaching in organizational settings has grown massively over the past couple of decades, as have the models, approaches, and sets of questions and techniques. What we do in this module, however, is go back to the tried and tested basics. In simple terms, the models techniques and so on that you apply are not going to deliver consistent benefits to your clients, if they deliver any benefits at all. It is those deep seated understandings and skills that make the difference. This is explained in some of the video clips provided and in the books listed under recommended reading
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