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Technical Paper

Spin Resistance Development for Small Airplanes - A Retrospective

2000-05-09
2000-01-1691
With the resurgence of the General Aviation industry, the incentive to develop new airplanes for the low-end market has increased. Increased production of small airplanes provides the designers and manufacturers the opportunity to incorporate advanced technologies that are not readily retrofitable to existing designs. Spin resistance is one such technology whose development was concluded by NASA during the 1980’s when the production of small airplanes had slipped into near extinction. This paper reviews the development of spin resistance technology for small airplanes with emphasis on wing design. The definition of what constitutes spin resistance and the resulting amendment of the Federal Aviation Regulations Part 23 to enable certification of spin resistant airplanes are also covered.
Technical Paper

Review of Organic Friction Modifiers - Contribution to Fuel Efficiency?

2000-06-19
2000-01-1792
Friction modifiers have been around for many years. Originally, the application was for limited slip gear oils, automatic transmission fluids and multipurpose tractor fluids. Since fuel economy became an international issue, initially to reduce crude oil consumption, friction modifiers have been introduced into automotive crankcase lubricants as well. The current emphasis is to improve the fuel efficiency through the engine lubricant and to reduce emissions to the environment. This paper describes the chemistry of the various organic friction modifiers as well as the non-organic types. A basic understanding is given on the mechanisms how and why these products work as friction modifiers and what is known about structure - activity relationships. Definitions are given about the various lubrication regimes as well as figures to what extend these regimes are present in current engine tests measuring fuel economy.
Technical Paper

Rheology of Used Diesel Lubricants When Contaminated with Soot - The Brookfield Measurement Opportunity

2000-06-19
2000-01-1808
Used Diesel oil viscosity is commonly measured by the kinematic method as outlined in the Mack T-8 used diesel soot procedure (ASTM D 5967 for used oil from Mack T-8 engine test, and CEC L-83-A-97 for used oil from PSA XUD11 ATE engine test). The limitations of the kinematic viscosity measurement for used oils heavily loaded with carbonaceous matters, have led to a new proposed method which may be better suited for these oils. This paper describes an investigation about the rheology of Diesel oils heavily loaded with carbonaceous matters. The kinematic viscosity result (measured with only the first sphere) was presented as a function of shear rate (imposed by differents kinematic viscometers) and demonstrated that the behaviour of these oils is not newtonian for low shear rates.
Technical Paper

Identifying the Environmental Impact Drivers and Tradeoff Options in the Life Cycle of Automobiles - A Software Based Methodology for the Sound Restriction of System Boundaries

2000-04-26
2000-01-1493
Life cycle assessments (LCA) require extensive quantities of data on processes as well as on material and energy flows. Therefore, simplifying methods that reduce the effort in modeling the product system do have the most potential to make reliable LCAs of complex products like automobiles more efficient. Methodological approaches allowing the LCA practitioner to conduct the scope definition and life cycle inventory (LCI) with minimal effort through “smart” software based support are introduced. The suggested methodology has been validated with a case study on material options for a front subframe system of a Ford passenger car.
Technical Paper

ECOTEC-GM's New Global 4-Cylinder Engine

2000-03-06
2000-01-1392
ECOTEC is the new Global 4-Cylinder engine designed and developed with participation by GM organizations and experts worldwide for vehicle applications in markets around the world. The four areas of significance within the paper are: Definition of product specifications so as to meet the functional and regulatory requirements for all marketing regions; description of the technical solution and the design/development process for the components; implementation of the best common manufacturing systems at multiple locations around the world; and overall program management.
Technical Paper

Heat Pipe Application for Thermal Stable Bench Arrangement in Small Satellite Design

2000-07-10
2000-01-2460
Heat pipes efficiency for space thermal engineering is widely recognized and illustrated. Among majority of heat transfer tasks the heat pipe employment for high precision optical devices' thermal control is interesting and challenging. The main heat pipe functions are associated with a) heat removal tasks in the wide temperature range (90 ÷ 300 K), b) heat transfer and redistribution inside/outside of system, c) providing of isothermality of mounting plate (seats) of devices; d) regulating of temperature in selected device or group of devices. The brief description of technical realization example of heat pipe application in peculiarities of small satellite design is subject of this report.
Technical Paper

Biological Wastewater Processor Experiment Definition

2000-07-10
2000-01-2468
The Biological Wastewater Processor Experiment Definition team is performing the preparatory ground research required to define and design a mature space flight experiment. One of the major outcomes from this work will be a unit-gravity prototype design of the infrastructure required to support scientific investigations related to microgravity wastewater bioprocessing. It is envisioned that this infrastructure will accommodate the testing of multiple bioprocessor design concepts in parallel as supplied by NASA, small business innovative research (SBIR), academia, and industry. In addition, a systematic design process to identify how and what to include in the space flight experiment was used.
Technical Paper

Simple Experimental Methods for Measurement of Heat Capacities for Electronic and Structure Components

2000-07-10
2000-01-2495
For the prediction of the transient behavior of thermal nodes which are interacting within a Thermal Mathematical Model (TMM) it is necessary to know the heat capacity of each node. For instance this is actual for components of opto-electronic devices for space exploration. Other assignment is to define the thermal properties of new structure materials and their combinations. Often the base for the correction of the TMM is the comparison of the calculated node temperatures with the node temperatures measured on a Thermal Engineering Model (TEM) during a Thermal Vacuum Test. The TEM has to be very similar to the flight hardware from the thermal point of view. But very expensive flight components are replaced in the TEM by thermal equivalent dummies. This makes it possible to use all components of the TEM for an unusual but simple experimental determination of their heat capacity as well.
Technical Paper

Data Exchange Using STEP Now Really Working

2000-07-10
2000-01-2524
STEP-TAS and STEP-NRF are two companion, open standards for electronic exchange and archival of space engineering data based on STEP (ISO-10303) technology: STEP-TAS: Definition of space missions and models used in thermal analysis. STEP-NRF: Discipline-independent protocol for the definition of analysis, test or operation cases/models and the bulk results produced by running such cases/models. Associated with these standards, some high-level programs have been developed for helping with the implementation of these protocols into user applications. Now, the STEP-TAS standard has started its industrial deployment phase in Europe with the incorporation into thermal software like ESARAD and THERMICA, while the first STEP-NRF proof-of concept implementations have started with software like CORATHERM from Alcatel Space.
Technical Paper

Integrated Orbiter/International Space Station Air Quality Analysis for Post-Mission 2A.1 Risk Mitigation

2000-07-10
2000-01-2250
Crewmember ingress of the International Space Station (ISS) before that time accorded by the original ISS assembly sequence, and thus before the ISS capability to adequately control the levels of temperature, humidity, and carbon dioxide, poses significant impacts to ISS Environmental Control and Life Support (ECLS). Among the most significant considerations necessitated by early ingress are those associated with the capability of the Shuttle Transportation System (STS) Orbiter to control the aforementioned levels, the capability of the ISS to deliver the conditioned air among the ISS elements, and the definition and distribution of crewmember metabolic heat, carbon dioxide, and water vapor. Even under the assumption that all Orbiter and ISS elements would be operating as designed, condensation control and crewmember comfort were paramount issues preceding each of the ISS Missions 2A and 2A.1.
Technical Paper

Mathematical Conceptualization of Kalicosmia

2000-07-10
2000-01-2333
We discuss herein the mathematical conceptualization of Kalicosmia (past and future of architecture). Definitions of Kalicosmia are constructed in order to conceptulize the subject; two lemmas are discussed and evaluated: one on the relation between volumetric mass and construction speed, and the ther on spatial volume available in a building. Spatial volume available in an architectonic building is calculated, and fundamental theorem of fractal architecture theory is discussed. Kalicosmia, volumetric mass M, housing surface E, construction speed V, convergence
Technical Paper

Thermal Balance Testing of the Envisat Payload Module

2001-07-09
2001-01-2242
The Envisat spacecraft has a launch mass greater than 8.0 tonnes and external dimensions of 10.0 metres x 2.8 metres x 2.1 metres. Due to it’s large size, it was necessary to perform the thermal balance and thermal vacuum testing in two stages. Firstly, there was the testing of the Service Module and, secondly, the testing of the Payload Module (PLM). This paper discusses the thermal balance testing of the PLM. The PLM, itself, is 7.5 metres tall; too large to fit into a test facility solar beam. Originally, it was intended to conduct two solar beam tests; one for the upper part and the second for the lower part. Following a revision and re-scheduling within the programme, it was decided to perform a single, non-solar beam, thermal balance test. The thermal balance test would be performed using test specific, electrical, heaters and test facility shroud control.
Technical Paper

Digital Definition of the Deflected Shape of the Human Body in Seated Postures for Ergonomic Design in CAD Models

2001-06-26
2001-01-2106
An advanced biofidelic shape of the human body is needed in computer-aided design (CAD) models for ergonomic design. To be used in seat and automotive design, this advance in biofidelity must be a 3D CAD tool that includes the deflected shape of the human body and must include skeletal landmarks, especially those related to load paths. The CAD tools must represent the range of the population and must also represent the full range of seated postures. To develop our CAD models, a 3D anthropometric study was undertaken that used skeletal landmarks to define relative positions of transverse cross-sections that describe both the “visible” and “invisible” shape of the seated body. Data were collected on large males, average males and small females. Subjects were measured in several postures while sitting on flat foam pads. Transverse sections were measured at the center of gravity of each thigh, under the ischial tuberosities and at the S2, L4, T8 and T4 spinal levels.
Technical Paper

Program Architecture for the Robotic Exploration of Mars

2001-07-09
2001-01-2137
NASA has recently completed the definition of a new architecture for the exploration of Mars. This paper will present a summary of the new Mars Exploration Program (MEP) architecture, along with a description of the resulting mission queue and science investigations.
Technical Paper

Crew Size, Composition, and Time: Implications for Habitat and Workplace Design in Extreme Environments

2001-07-09
2001-01-2139
The authors report the results of an ongoing study that investigates the effects of crew size, composition, mission duration, and mission interval on behavior and performance among polar and space expeditions. The standardized rates for a behavior/performance indicator constructed during the pilot study displayed distinctive patterns across different crew profiles and settings. Then, a further analysis over the missions in the pilot sample found compelling information suggesting that several factors created specific differentials between outside (baseline) groups (e.g., mission controllers, “folks back home”) and groups in extreme environments. These differentials reflected how the passage of time was subjectivized by crews and how the expeditionary situation was otherwise defined differently from baseline. These analyses suggest that the definition of the long-duration mission, such as a mission to Mars, likely involves more than the issue of real-time duration.
Technical Paper

Thermal Comfort Control of an Advanced Space Suit

2001-07-09
2001-01-2268
This paper proposes an optimal control strategy for thermal comfort control of an advanced space suit. During an extravehicular activity (EVA), the astronaut's metabolic rate is time-varying depending on the working load, which would prescribe different reference skin temperatures. The purpose of thermal comfort control is to control the skin temperature to the reference value at a certain metabolic rate via a liquid cooling garment (LCG) for astronaut comfort. MPC is expected to achieve the control with the minimum consumable energy. After developing an operational definition of comfort, the structure of the controller and preliminary results are reported.
Technical Paper

Preliminary results on emissions and driving behavior of ATENA fleet test project in Naples

2001-09-23
2001-24-0083
One of the objectives of the Atena project was the definition of methods for the predictive evaluation of the environmental impact of different types of vehicles used in an urban scenario. The target is to obtain a methodology that allows the decision maker to verify in simulation the effects of possible measures like the law enforcement to the access restrictions or vehicle fleet composition. The main obstacle is the realization and managing of real driving cycles in order to overtake the limits derived from the utilization of typical cycles (i.e., ECE + EUDC) or the simple consideration of average speed. The starting point is a digital representation of the urban network where all the roads are represented with one or more arcs and for all these arcs are available an estimation of the traffic variables like the vehicle flow (vehicles per hour) or the average speed (kph). Every arc is described in terms of traffic parameters like the type of road (i.e., highway, district road).
Technical Paper

Looking for the Design Limits: First Steps to Establish a New Methodology

2001-07-09
2001-01-2407
This paper presents a modest approach of a new type of methodology to design thermal subsystems based on the knowledge of the limits of the proposed designs and its capabilities to adopt changes since the early phases of the projects. The methodology is based on establishing two major contents. Firstly a thermal performance database using Monte Carlo and statistical results exploitation similar to the stochastic analysis discipline and secondly a thermal uncertainties database using pure stochastic analysis. As consequence, an attempt to redefine and compare the objectives of each of the present phase’s definition is provided.
Technical Paper

The Definition of Space Life Support System Preliminary Configuration Based on a Single Criteria Approach

2001-07-09
2001-01-2366
This paper reviews the preliminary definition of integrated life support system configurations based on a single criterion decision-making task (SCDMT). Comparative analysis results are shown for currently used effectiveness models based on SCDMT. Possible areas of application for those models are determined. It is also proven that well-known effectiveness model, which uses an equivalent mass approach to determine system expenditures, can be used only in cases where useful effect from system operation is the same. The article proposes the use of a global thermodynamic effectiveness criterion based on the exergy method to account for ECLSS functional expenditures, i.e. functional costs. Exergy is a concept that fuses energy and material quality information in a measure that is both descriptive and physically significant. This method accounts for nonequivalence of different forms of energy and allows measuring technological flows in the system using same measuring units.
Technical Paper

Methodology to Define the Design Specification of Injection Molded Component and its Application in the Automobile Industries

2001-03-05
2001-01-3928
In the process of definition the component design specifications, the dependence and interdependence among the requirements, rules, strategies and design recommendations should be considered. However, in the conceptual design phase, the level of abstraction of the available information is high, and the methodologies present only superficial recommendations about the process to define design specifications. The consequences of these approach are reflected on the generation of conceptions with high costs and lost of resources during the design process. The objective of this paper is to present a methodology to define the design specifications, its application in the design of injection molded components and the software SISCOI developed to support this activity.
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