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Technical Paper

R134A Suction Line Heat Exchanger in Different Configurations of Automotive Air-Conditioning Systems

2001-05-14
2001-01-1694
A suction line heat exchanger (SLHX) transfers heat from the condenser outlet to the suction gas. In a TXV (thermostatic expansion valve) system, the performance improvement with a 60 to 80 % effective SLHX is expected to be on the order of 8 to 10 % for capacity, and 5 to 7 % for COP for high outdoor air temperatures of 43ºC. In a FOT (fixed orifice tube) system, the performance improvement was calculated to be about 10 to 15 %. The calculated improvements have been verified experimentally within a few percent.
Technical Paper

Analysis of Coatings Appearance and Durability Testing Induced Surface Defects Using Image Capture/Processing/Analysis

2001-03-05
2001-01-3798
This paper describes the applicability of optical imaging techniques to the analysis of the scratch resistance of automotive interior plastic materials. The evaluation of so-called “finger testing” has traditionally relied upon human vision for detection of the initial scratch position. Commonly performed under uniform and defined illumination conditions, the relative contrast difference signified by whitening on a surface as determined by unaided human vision is a highly variable subjective perception; thus individual inspectors may determine the “whitening” point differently. This paper compares test data obtained from both visual and instrumental evaluation methods and discusses the advantages of optical imaging techniques for surface defect analysis.
Technical Paper

An Electric Power Generation System for Launch Vehicles

2006-11-07
2006-01-3061
Launch vehicles that use electric actuators for thrust vector or flight control require a safe, reliable and lightweight source of electrical power. Honeywell, working with NASA Glenn Research Center and Lockheed Martin Space Systems, has developed and successfully tested a turbine-driven electric power generation system which meets these needs. This Turbine Power Unit (TPU) uses hydrogen and oxygen propellants which react catalytically to drive a shaft-speed turboalternator mounted on foil bearings. A high-reactance permanent-magnet machine (HRPMM) was selected for this application. The power conditioning and control electronics can be located within the TPU housing and the hydrogen fuel can be used to pressurize the bearings and electronics and to regeneratively cool the machine. A brassboard unit incorporating many of these features was successfully tested at output power levels from 0 to 138 kilowatts (kW).
Technical Paper

Power Distribution for Spacecraft Payloads that Employ State of the Art Radiation Hardened Integrated Circuits

2006-11-07
2006-01-3058
Recent advances in the state of the art of space-borne data processors and signal processors have occurred that present some unprecedented constraints relating to their power needs. Such processors include the class of multiprocessors providing computational capabilities in the billions of floating point operations per second. Processors of this type tend to require use of modern radiation tolerant or radiation hardened integrated circuits requiring very low voltage power supplies that place considerable challenge on power distribution and conversion within those processing payloads. The primary challenges are efficient conversion of power from the spacecraft power bus to these low voltages and distribution of the very high accompanying currents within the payload while maintaining proper voltage regulation (typically +/− 5%). Some integrated circuits require 10 Amps or more at 1Volt, as an example [3], [6].
Technical Paper

Design and Development of Light Weight Al Spindle

2002-03-04
2002-01-0676
The demand for improved vehicle fuel economy drives the auto engineers to look for opportunities in weight reduction of automotive systems and components. This paper presents inventions on the design and development of a lightweight spindle. In this new product, the spindle body is made from an Al alloy for a substantial weight reduction in comparison to the tradition iron spindle body. The shaft of the spindle is made from high strength steel to meet strength requirements. The design shows the unique feature of the joining area between the spindle body and shaft. The related joining process is applied to produce a strong joint between the two parts made of different materials. The testing results will be presented and discussed.
Technical Paper

Novel High Performance Fiber-High Speed Test Development

2002-03-04
2002-01-0681
The major objective of this paper is to address how the actual force versus extension relationship for a seat belt during a collision is different from the one obtained at typical low rate (static) conditions. We also look at what features of the tensile stress-strain characteristic are important for the optimal performance of a seat belt. To answer these questions experimentally we use our high rate Instron -1331. We also designed an experimental set up that required special grips and contact sensors for characterizing samples of belt and yarn. In the theoretical part we demonstrate the selected rates for the tensile testing as relevant to the collisions. We also discuss the importance of the energy absorbing capacity of the belts as the most relevant characteristic of the tensile curves for this application. We then show the effect of visco-elastic factors on energy absorbing properties of fibers during collisions and the role of weaving and dyeing the belt.
Technical Paper

Effect of Post Brazed Flux Residues of CAB Evaporators on the Consistency of Conversion Coating

2005-04-11
2005-01-1773
Evaporators for automotive air-conditioning systems are being coated externally to improve corrosion resistance, water drainage, and reduce potential odor concerns. The coating durability and efficiency in achieving its corrosion resistance depends on the coating uniformity and adhesion characteristics. Good coating adhesion on aluminum surface can be achieved after freeing the surface from the oxide and flux residues. Evaporators manufactured by the Controlled Atmosphere Brazing (CAB) process have flux residue remaining on the surface, the presence of which interferes with the coating process and also affects the performance of coated components. A methodology to quantify the effect of high Nocolok flux residue on heat exchanger coating uniformity has been presented.
Technical Paper

Non-Linear Analysis of Tunable Compression Bushing for Stabilizer Bars

2004-03-08
2004-01-1548
Stabilizer bars in a suspension system are supported with bushings by a frame structure. To prevent the axial movement of the stabilizer bar within the bushing, several new stabilizer bar-bushing systems have been developed. The new systems introduce permanent compressive force between the bar and the bushing thereby preventing the relative movement of the bar within the bushing. This mechanical bond between the bar and the bushing can eliminate features such as grippy flats, collars etc. In addition, by controlling the compression parameters, the properties of the bushing such as bushing rates can be tuned and hence can be used to improve the ride and handling performance of the vehicle. In this paper, nonlinear CAE tools are used to evaluate one such compressively loaded bushing system. Computational difficulties associated with modeling such a system are discussed.
Technical Paper

Ersatz Wastewater Formulations for Testing Water Recovery Systems

2004-07-19
2004-01-2448
This paper addresses the derivation of chemical ersatz recipes for use in the evaluation of development hardware designed for advanced spacecraft water recovery systems. The recipes simulate characteristics of wastewater generated on a transit mission and on an early planetary base (EPB). In addition, recipes are provided which simulate the water quality of the early planetary base wastewater as it moves through a combination biological and physical-chemical water recovery system. These ersatz are considered to be accurate representations of the wastewater as it passes through primary, secondary, and tertiary processing stages. The EPB ersatz formulas are based on chemical analyses of an integrated water recovery system performance test that was conducted over a period of one year. The major inorganic and organic chemical impurities in the raw wastewater, and in the effluent from the various subsystems, were identified and quantified.
Technical Paper

Selection of an Alternate Biocide for the ISS Internal Thermal Control System Coolant - Phase II

2004-07-19
2004-01-2472
The ISS (International Space Station) ITCS (Internal Thermal Control System) includes two internal coolant loops that utilize an aqueous based coolant for heat transfer. A silver salt biocide had previously been utilized as an additive in the coolant formulation to control the growth and proliferation of microorganisms within the coolant loops. Ground-based and in-flight testing demonstrated that the silver salt was rapidly depleted, and did not act as an effective long-term biocide. Efforts to select an optimal alternate biocide for the ITCS coolant application have been underway and are now in the final stages. An extensive evaluation of biocides was conducted to down-select to several candidates for test trials and was reported on previously.
Technical Paper

A Selected Operational History of the Internal Thermal Control System (ITCS) for International Space Station (ISS)

2004-07-19
2004-01-2470
The Internal Thermal Control System (ITCS) has been developed jointly by Boeing Corporation, Huntsville, Alabama and Honeywell Engines & Systems, Torrance, California to meet the internal thermal control needs for the International Space Station (ISS). The ITCS provides heat removal for the critical life support systems and thermal conditioning for numerous experiment racks. The ITCS will be fitted on a number of modules on the ISS. The first US Element containing the ITCS, Node 1, was launched in December 1998. Since Node 1 does not contain a pump to circulate the fluid it was not filled with ITCS fluid until after the US Laboratory Module was installed. The second US Element module, US Laboratory Module, which contains the pumps and all the major ITCS control hardware, was launched in February 2001. The third US Element containing the ITCS, the US Airlock, was launched in July 2001.
Technical Paper

International Space Station Carbon Dioxide Removal Assembly (ISS CDRA) Troubleshooting and Evaluation

2004-07-19
2004-01-2548
An important aspect of air revitalization for life support in spacecraft is the removal of carbon dioxide from cabin air. Several types of carbon dioxide removal systems are in use in spacecraft life support. These systems rely on various removal techniques that employ different architectures and media for scrubbing CO2, such as permeable membranes, liquid amine, adsorbents, and absorbents. Sorbent systems have been used since the first manned missions. The current state of key technology is the existing International Space Station (ISS) Carbon Dioxide Removal Assembly (CDRA), a system that selectively removes carbon dioxide from the cabin atmosphere. The CDRA system was launched aboard UF-2 in February 2001 and resides in the U.S. Destiny Laboratory module. During the past three years, the CDRA system has operated with varying degrees of success.
Technical Paper

Human Factors Flight Test Evaluation of an Airport Surface Display with Indications & Alerts (SURF IA)

2010-09-30
2010-01-1663
This paper presents the results of a human factors flight test evaluation of a display of Enhanced Traffic Situational Awareness on the Airport Surface with Indications and Alerts (SURF IA). The study is an element of the FAA-sponsored Surface Conflict Detection and Alerting with Consideration of Arrival Applications program. The objective of the flight test was to conduct a comparative evaluation of two candidate SURF IA displays: a detailed Airport Surface Situation Awareness (ASSA) display and a runways-only Final Approach Runway Occupancy Awareness (FAROA) display. Six pilots with a current Air Transport Pilot Certificate each completed 18 scenarios. A Beechcraft King Air C-90 and a Cessna Citation Sovereign aircraft were deployed for the flight tests. The scenarios were conducted at Seattle-Tacoma International Airport and at Snohomish County Paine Field Airport, with each aircraft acting as ‘traffic’ for the other aircraft.
Technical Paper

Production Solutions for Utilization of Both R1234yf and R134a in a Single Global Platform

2009-04-20
2009-01-0172
As global automobile manufacturers prepare for the phase-out of R134a in Europe, they must address the issue of using the new refrigerant for European sales only or launching the product worldwide. Several factors play into this decision, including cost, service, risk, customer satisfaction, capacity, efficiency, etc. This research effort addresses the minimal vehicle-level hardware differences necessary to provide a European solution of R1234yf while continuing to install R134a into vehicles for the rest of the world. It is anticipated that the same compressor, lubricant and condenser; most fluid transport lines; and in most cases the evaporator can be common between the two systems.
Technical Paper

Blind Spot Monitoring by a Single Camera

2009-04-20
2009-01-1291
A practical and low cost Blind Spot Monitoring system is proposed. By using a single camera, the range and azimuth position of a vehicle in a blind spot are measured. The algorithm is based on the proposed RWA (Range Window Algorithm). The camera is installed on the door mirror and monitoring the side and rear of the host vehicle. The algorithm processes the image and identifies range and azimuth angle of the vehicle in the adjacent lane. This algorithm is applied to real situations. The 388 images including several kinds of vehicles are analyzed. The detection rate is 86% and the range accuracy is 1.6[m]. The maximum detection range is about 30[m].
Technical Paper

Selection of an Alternate Biocide for the International Space Station Internal Active Thermal Control System Coolant Loops

2003-07-07
2003-01-2568
The International Space Station (ISS) IATCS (Internal Active Thermal Control System) includes two internal coolant loops that use an aqueous based coolant for heat transfer. A silver salt biocide was used initially as an additive in the coolant formulation to control the growth and proliferation of microorganisms in the coolant loops. Ground-based and in-flight testing has demonstrated that the silver salt is rapidly depleted and not effective as a long-term biocide. Efforts are now underway to select an alternate biocide for the IATCS coolant loop with greatly improved performance. An extensive evaluation of biocides was conducted to select several candidates for test trials.
Technical Paper

Breadboard Development of the Advanced Inflatable Airlock System for EVA

2003-07-07
2003-01-2449
The advanced inflatable airlock (AIA) system was developed for the Space Launch Initiative (SLI). The objective of the AIA system is to greatly reduce the cost associated with performing extravehicular activity (EVA) from manned launch vehicles by reducing launch weight and volume from previous hard airlock systems such as the Space Shuttle and Space Station airlocks. The AIA system builds upon previous technology from the TransHab inflatable structures project, from Space Shuttle and Space Station Airlock systems, and from terrestrial flexible structures projects. The AIA system design is required to be versatile and capable of modification to fit any platform or vehicle needing EVA capability. During the basic phase of the program, the AIA conceptual design and key features were developed to help meet the SLI program goals of reduced cost and program risk.
Technical Paper

Finite Element Study of a Composite Tube Under Impact Load

2002-03-04
2002-01-0723
Composite materials can be used effectively for structural applications where high strength-to-weight and stiffness-to-weight ratios are required. Although the design and analysis techniques for static, buckling and vibration loadings are fairly well established, methodologies for analysis of composite structures under impact loading are still a major research activity. This paper presents a nonlinear finite-element analysis method to analyze a composite structure subjected to axial impact load. The analysis was performed using MSC/DYTRAN FE code while pre and post processing were done using MSC/PATRAN program. In addition, a steel tube of the same geometry was analyzed for comparison purpose.
Technical Paper

Environmental Systems Considerations for Aircraft Cabins During Ground Operation

2002-11-05
2002-01-2941
The quality of outside air during ground operations was analyzed by comparing airport and engine exhaust data to exposure limits and odor thresholds. The results indicated that the outside air may contain compounds in high enough concentrations to be odorous. If the odor is to be treated, the important design criteria that must be considered include the phase of compounds, compound type, location of treatment device on the aircraft, pressure drop, operating temperature, and maintenance interval. Finally, a control strategy is outlined that monitors the air quality as well as the efficiency of an air treatment system.
Technical Paper

Performance and Benefits of Zero Maintenance Air Induction Systems

2005-04-11
2005-01-1139
Engine air filtration technologies currently used in air induction systems typically utilize pleated paper or felt type air filters. These air filter designs have been used for many years in panels, cylindrical or round (pancake type) type air cleaners. Pleated air filters are specifically designed to be serviceable and hence their performance is inherently limited by vehicle under-hood packaging and manufacturing constraints. Due to these constraints, majority of air cleaner designs are not optimized for engine filtration and air flow management under the hood. Studies show that use of low performing serviceable aftermarket air filters significantly affect the performance and durability of engine air cleaners [9]. High mileage studies confirm that engine durability, service issues, warranty field returns and customer satisfaction was affected by use of aftermarket filter brands.
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