SCIENTIFIC AND TECHNICAL AEROSPACE REPORTS

A Biweekly Publication of the National Aeronautics and Space Administration
VOLUME 44, ISSUE 10 - MAY 19, 2006

20 SPACECRAFT PROPULSION AND POWER
Includes main propulsion systems and components, e.g., rocket engines; and spacecraft auxiliary power sources.

For related information see also 07 Aircraft Propulsion and Power, 28 Propellants and Fuels, 15 Launch Vehicles and Launch Operations, and 44 Energy Production and Conversion.

20060012212 Environmental Protection Agency, Washington, DC USA

Final Regulatory Support Document: Control of Emissions from Highway Motorcycles

Dec. 2003; 220 pp.; In English Report No.(s): PB2006-108466; EPA/420/R-03/015; No Copyright; Avail.: CASI: A10, Hardcopy

This Final Regulatory Support Document provides economic, technical, cost, and environmental analyses of the new permeation evaporative and exhaust emission standards for highway motorcycles. The anticipated emission reductions will translate into meaningful, long term improvements in air quality in many areas of the U.S. Overall, the new requirements will reduce individual exposure to dangerous pollutants and provide much needed assistance to states and regions facing ozone and particulate air quality problems that are causing a range of adverse health effects, especially in terms of respiratory impairment and related illnesses. Chapter 1 reviews information related to the health and welfare effects of the pollutants of concern. Chapter 2 contains an overview of the affected manufacturers, including some description of the range of vehicles/engines involved and their place in the market. Chapter 3 covers a broad description of engine and permeation evaporative emission control technologies, including a wide variety of approaches to reducing emissions. Chapter 4 summarizes the available information specifically providing a technical justification for the feasibility of the standards. Chapter 5 applies cost estimates to the projected technologies. Chapter 6 presents the calculated contribution of these sources to the nationwide emission inventories with and without the new standards. Chapter 7 compares the costs and the emission reductions for an estimate of the cost-effectiveness of the rulemaking. Chapter 8 presents our Small Business Flexibility Analysis, which evaluates the impact of the rule on small businesses. Market Overview This regulation is designed to achieve emission reductions from highway motorcycles. NTIS

Highways; Motor Vehicles

20060012258 NASA Goddard Space Flight Center, Greenbelt, MD, USA

Aerospace Battery Activities at NASA/Goddard Space Flight Center

Rao, Gopalakrishna M.; [2006]; 37 pp.; In English; International Battery Association and Battery Conference, 9-12 Jan. 2006, Waikola, HI, USA; Original contains color illustrations; No Copyright; Avail.: CASI: A03, Hardcopy

Goddard Space Flight Center has 'pioneered' rechargeable secondary battery design, test, infusion and in-orbit battery management among NASA installations. Nickel cadmium batteries of various designs and sizes have been infused for LEO, GEO and Libration Point spacecraft. Nickel-Hydrogen batteries have currently been baselined for the majority of our missions. Li-Ion batteries from ABSL, JSB, SaFT and Lithion have been designed and tested for aerospace application. Derived from text

Nickel Cadmium Batteries; Nickel Hydrogen Batteries; Electric Batteries; Storage Batteries; Libration; Project Management

20060012337 NASA Glenn Research Center, Cleveland, OH, USA

Reliability of Radioisotope Stirling Convertor Linear Alternator

Shah, Ashwin; Korovaichuk, Igor; Geng, Steven M.; Schreiber, Jeffrey G.; April 2006; 14 pp.; In English; Space Technology and Applications International Forum (STAIF-2005), 13-17 Feb. 2005, Albuquerque, NM, USA; Original contains color illustrations Contract(s)/Grant(s): NAS3-03064; WBS 22-972-20-01 Report No.(s): NASA/TM-2006-213636; E-15119; Copyright; Avail.: CASI: A03, Hardcopy

Onboard radioisotope power systems being developed and planned for NASA s deep-space missions would require reliable design lifetimes of up to 14 years. Critical components and materials of Stirling convertors have been undergoing extensive testing and evaluation in support of a reliable performance for the specified life span. Of significant importance to the successful development of the Stirling convertor is the design of a lightweight and highly efficient linear alternator. Alternator performance could vary due to small deviations in the permanent magnet properties, operating temperature, and component geometries. Durability prediction and reliability of the alternator may be affected by these deviations from nominal design conditions. Therefore, it is important to evaluate the effect of these uncertainties in predicting the reliability of the linear alternator performance. This paper presents a study in which a reliability-based methodology is used to assess alternator performance. The response surface characterizing the induced open-circuit voltage performance is constructed using 3-D finite element magnetic analysis. Fast probability integration method is used to determine the probability of the desired performance and its sensitivity to the alternator design parameters. Author

AC Generators; Stirling Cycle; Reliability; Permanent Magnets; Life Span; Design Analysis; Finite Element Method

20060013012 NASA Glenn Research Center, Cleveland, OH, USA

Parametric Investigation of Thrust Augmentation by Ejectors on a Pulsed Detonation Tube

Wilson, Jack; Sgondea, Alexandru; Paxson, Daniel E.; Rosenthal, Bruce N.; January 2006; 21 pp.; In English; 42st AIAA/ASME/SAE/ASEE Joint Propulsion Conference, 10-13 Jul. 2005, Tucson, AZ, USA; Original contains black and white illustrations Contract(s)/Grant(s): NAS3-00145; WBS 22-708-03-05 Report No.(s): AIAA Paper 2005-4208; No Copyright; Avail.: CASI: A03, Hardcopy

A parametric investigation has been made of thrust augmentation of a 1 in. diameter pulsed detonation tube by ejectors. A set of ejectors was used which permitted variation of the ejector length, diameter, and nose radius, according to a statistical design of experiment scheme. The maximum augmentation ratios for each ejector were fitted using a polynomial response surface, from which the optimum ratios of ejector diameter to detonation tube diameter, and ejector length and nose radius to ejector diameter, were found. Thrust augmentation ratios above a factor of 2 were measured. In these tests, the pulsed detonation device was run on approximately stoichiometric air-hydrogen mixtures, at a frequency of 20 Hz. Later measurements at a frequency of 40 Hz gave lower values of thrust augmentation. Measurements of thrust augmentation as a function of ejector entrance to detonation tube exit distance showed two maxima, one with the ejector entrance upstream, and one downstream, of the detonation tube exit. A thrust augmentation of 2.5 was observed using a tapered ejector. Author

Ejectors; Detonation; Thrust; Experiment Design

20060013034 Environmental Protection Agency, Washington, DC USA

Summary and Analysis of Comments: Control of Emissions from Highway Motorcycles

Dec. 2003; 154 pp.; In English Report No.(s): PB2006-109228; EPA/420/R-03/016; No Copyright; Avail.: National Technical Information Service (NTIS)

On August 14, 2002, we published a Notice of Proposed Rulemaking (NPRM) for revised emission standards for highway motorcycles. In that notice, we proposed to largely align the federal exhaust emission standards with those of the California program, but on a delayed schedule relative to implementation in California.We also proposed exhaust emission standards for the currently unregulated category of motorcycles with displacements of less than 50 cc. We held a public hearing on the NPRM in Ann Arbor, Michigan on September 17, 2002. At that hearing, oral comments on the NPRM were received and recorded. A written comment period remained open until January 7, 2003. A complete list of organizations that provided comments on the NPRM is contained in the following table. Abbreviations for the organization names are also included. In addition to the organizations shown in the following table, we received comments from several thousand individuals. All comments and hearing testimony have been placed in Air Docket A-2000-02. This Summary and Analysis of Comments contains a detailed summary of all comments we received on the NPRM as well as our analysis of each comment and our response. The reader should also refer to the final rulemaking notice in the Federal Register as well as the Final Regulatory Support Document. NTIS

Air Pollution; Highways; Motor Vehicles; Pollution Control

Source: NASA