Scientific and Technical Aerospace Reports Volume 38 July 28, 2000

tion (NPSS), is focused on the integration of multiple disciplines such as aerodynamics, structures and heat transfer with computing
and communication technologies to capture complex physical processes in a timely and cost-effective manner. The vision for
NPSS, as illustrated, is to be a ”numerical test cell” that enables full engine simulation overnight on cost-effective computing platforms.
There are several key elements within NPSS that are required to achieve this capability: 1) clear data interfaces through
the development and/or use of data exchange standards, 2) modular and flexible program construction through the use of objectoriented
programming, 3) integrated multiple fidelity analysis (zooming) techniques that capture the appropriate physics at the
appropriate fidelity for the engine systems, 4) multidisciplinary coupling techniques and finally 5) high performance parallel and
distributed computing. The current state of development in these five area focuses on air breathing gas turbine engines and is
reported in this paper. However, many of the technologies are generic and can be readily applied to rocket based systems and combined
cycles currently being considered for low-cost access-to-space applications. Recent accomplishments include: (1) the
development of an industry-standard engine cycle analysis program and plug ’n play architecture, called NPSS Version 1, (2) A
full engine simulation that combines a 3D low-pressure subsystem with a 0D high pressure core simulation. This demonstrates
the ability to integrate analyses at different levels of detail and to aerodynamically couple components, the fan/booster and lowpressure
turbine, through a 3D computational fluid dynamics simulation. (3) Simulation of all of the turbomachinery in a modern
turbofan engine on parallel computing platform for rapid and cost-effective execution. This capability can also be used to generate
full compressor map, requiring both design and off-design simulation. (4) Three levels of coupling characterize the multidisciplinary
analysis under NPSS: loosely coupled, process coupled and tightly coupled. The loosely coupled and process coupled
approaches require a common geometry definition to link CAD to analysis tools. The tightly coupled approach is currently validating
the use of arbitrary Lagrangian/Eulerian formulation for rotating turbomachinery. The validation includes both centrifugal
and axial compression systems. The results of the validation will be reported in the paper. (5) The demonstration of significant
computing cost/performance reduction for turbine engine applications using PC clusters. The NPSS Project is supported under
the NASA High Performance Computing and Communications Program.
Author
Propulsion System Configurations; Computerized Simulation; Parallel Processing (Computers); Computer Aided Design; Mathematical
Models; Engine Design; Distributed Processing
20000066606 Prins Maurits Lab. TNO, Rijswijk, Netherlands
Occupational Health Risks of Exhaust Gases of the F-16 During Operational Exercises with the 40L70 Final Report Arbeidshygienische
Risico’s Door Uitlaatgassen uit de F-16 Tijdens Operationele Oefeningen met de 40L0
Groeneveld, F. R., Prins Maurits Lab. TNO, Netherlands; February 2000; 26p; In Dutch; Original contains color illustrations
Contract(s)/Grant(s): A99,KLu/431; TNO Proj. 014.11168
Report No.(s): TD99-0420; PML-1999-A104; Copyright; Avail: Issuing Activity
The personnel of the canon 40L70 are feeling inconvenience by the exhaust of the F-16 positioned at the top of runway 24
at Twenthe air base during operational exercises. An unfavourable wind the exhaust gases were blowing over their fixed position
of the 40L70. After measurements of several compounds of the exhaust gases the concentrations did not exceed the MAC-value
at a distance of 100 meter below the wind of the F-16.
Derived from text
Exhaust Gases; Personnel; F-16 Aircraft
20000067666 NASA Glenn Research Center, Cleveland, OH USA
A Probabilistic Approach to Aeropropulsion System Assessment
Tong, Michael T., NASA Glenn Research Center, USA; Jan. 31, 2000; 8p; In English; 45th; Gas Turbine and Aeroengine Technical
Congress, 8-11 May 2000, Munich, Germany; Sponsored by American Society of Mechanical Engineers, USA
Contract(s)/Grant(s): RTOP 522-70-03; No Copyright; Avail: CASI; A02, Hardcopy; A01, Microfiche
A probabilistic approach is described for aeropropulsion system assessment. to demonstrate this approach, the technical performance
of a wave rotor-enhanced gas turbine engine (i.e. engine net thrust, specific fuel consumption, and engine weight) is
assessed. The assessment accounts for the uncertainties in component efficiencies/flows and mechanical design variables, using
probability distributions. The results are presented in the form of cumulative distribution functions (CDFS) and sensitivity analyses,
and are compared with those from the traditional deterministic approach. The comparison shows that the probabilistic
approach provides a more realistic and systematic way to assess an aeropropulsion system.
Author
Distribution Functions; Gas Turbine Engines; Probability Theory; Wave Rotors; Mechanical Engineering; Propulsion System
Performance
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