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Occupant protection was the focal point of the first work in the area of experimental safety vehicles. These first vehicles were heavy and expensive. The second generation of vehicles were designed with more realistic safety features and the goal for mass production. Complying with the modified objectives, the ESVW II was designed by Volkswagenwerk.

Exhaust carbon concentration data provides a valuable look into the diesel engine combustion process. This type of information provides engineers with a qualitative determination of soot and organic particulate released to the ambient air by the engine, or after-treatment system. Although this type of information has been available for many years, the cost and time consuming nature of these laboratory tests has relegated them, until now, to a secondary position. With the emergence of automated instruments designed to provide on-line exhaust carbon concentration information in the test cell, this secondary position has now changed. Using devices like the Series 5100 Diesel Particulate Measurement System, engineers can receive rapid feedback about engine emissions and combustion.

In the present work, a multi-zone model is presented for the simulation of HCCI engines. This model is an improvement of a previous one developed by the authors. The present model describes the combustion, heat and mass transfer processes for the closed part of the engine cycle, i.e. compression, combustion and expansion. The zones occupy geometrical positions within the engine cylinder and exchange heat and mass throughout the compression and expansion strokes, based on their spatial configuration. Heat exchange is considered between zones and to the cylinder wall. A phenomenological model has been developed to describe mass exchange between zones and the flow of a portion of the in-cylinder mixture in and out of the crevice region. The crevice flow is a new feature and is included in the present model since the crevice regions are considered to contribute to unburned HC emissions. Another new feature is the incorporation of chemical kinetics, based on combustion chemistry reactions.

On the basis of the large amount of know-how accumulated in the field of automotive ethanol SI-engine fuelling in Brazil, it seemed appropriate to continue and set a new milestone in the usage of ethanol fuel. The paper presents the preliminary study made to enable the transfer of the ethanol technology to a 5.9-liter 4-cylinder boxer aircraft engine. The study describes the steps made to define the optimal parameter configuration for the transfer of the fuel system packaging, the fuel injector layout, the engine control unit (ECU) and the legislative redundancy requirements for aviation applications. The paper illustrates the use of numerical simulation techniques and special visualization approaches necessary to understand the physical phenomena of mixture preparation (spray atomization and momentum). Two different layouts are presented and discussed and a certain number of experimental results obtained with the retained solution are presented and discussed.

1 The demand for vehicles with improved fuel efficiency and controlled emissions is increasing year after year. The Hybrid Electric Vehicle (HEV), which combines an internal-combustion engine and an electric motor, currently seems to be the most promising new technology. Many HEVs of various forms have been developed and their commercialization is proceeding. The Integrated Motor Assist (IMA) system described in this present paper is classified in the parallel HEV category. This system offers a lightweight and compact power plant due to its simple configuration. The motor of the IMA system is connected directly to the engine crankshaft via the flywheel located between a 1000cc three-cylinder gasoline engine and the transmission.

The National Aeronautics and Space Administration (NASA), Lewis Research Center (LeRC) is responsible for the development, fabrication, and assembly of the electric power system (EPS) for the Space Station Freedom (SSF). The Power Management and Distribution (PMAD) Systems Testbed was assembled to support the design and early evaluation of SSF EPS operating concepts. The PMAD Systems Testbed represents a portion of the SSF EPS, containing intelligent switchgear, power conditioning devices, and the EPS Controllers. The PMAD Systems Testbed facility is discussed, including the power sources and loads available. A description of the PMAD Data System (PDS) is presented. The PDS controls the testbed facility hardware, monitors and records the EPS control data bus and external data. The external data includes testbed voltages and currents along with facility temperatures, pressures, and flow rates. Transient data is collected utilizing digital oscilloscopes.

The NASA Lewis Research Center in Cleveland, Ohio has completed the development and integration of a Power Management and Distribution (PMAD) DC Testbed. This testbed is a reduced scale representation of the end to end, sources to loads, Space Station Freedom Electrical Power System (SSF EPS). This unique facility is being used to demonstrate DC power generation and distribution, power management and control, and system operation techniques considered to be prime candidates for the Space Station Freedom. A key capability of the testbed is its ability to be configured to address system level issues in support of critical SSF program design milestones. Electrical power system control and operation issues like source control, source regulation, system fault protection, end-to-end system stability, health monitoring, resource allocation and resource management are being evaluated in the testbed.

The paper describes a new passive restraint system, the Volkswagen Restraint Automatic (VW-RA). The system consists of an upper torso belt and an energy-absorbing knee bolster. The operation of the system is automatic as it is attached to the door of the vehicle. The comparison with the three-point belt having a vehicle-sensitive locking retractor and airbag systems shows that the overall performance of the VW-RA is superior to the other systems. A fleet test of 50 vehicles in the United States will determine acceptability to the consumer.

The two new facilities have been installed and operated at their design or rated conditions. The important feature of both of these facilities is that the ratio of turbine inlet temperature to coolant temperature encountered in high temperature engines can be duplicated at moderate turbine inlet temperature. Included in the discussion are the limits of the facilities with regard to maximum temperature, maximum pressure, maximum mass flow rate, turbine size, and dynamometer torque-speed characteristics.

This Aerospace Information Report (AIR) provides information on systems integration rigs, commonly referred to as “Iron Birds” for aerospace applications. a It includes background historical information including descriptions of Iron Birds produced to date, important component elements and selection rationale, hydraulic system design and operational modes and illustrates the design approaches to be considered. b It provides illustrations of the various systems that should be considered for Iron Bird testing in the development phase and utilization during the production program. c It includes recommendations for simulation, component development tests, system integration and lessons learned.

During the first two weeks of September 2005, the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) Advanced Extravehicular Activity (AEVA) team led the field test portion of the 2005 Research and Technology Studies (RATS). The Desert RATS field test activity is the culmination of the various individual science and advanced engineering discipline areas year-long technology and operations development efforts into a coordinated field test demonstration under representative (analog) planetary surface terrain conditions. The purpose of the RATS is to drive out preliminary exploration concept of operations EVA system requirements by providing hands-on experience with simulated planetary surface exploration extravehicular activity (EVA) hardware and procedures.

During the first two weeks of September, 2006, the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) Advanced Extra Vehicular Activity (AEVA) team led the field test portion of the 2006 Desert Research and Technology Studies (D-RATS) in the Flagstaff, AZ area. The Desert RATS field test activity is the year-long culmination of various individual science and advanced engineering discipline areas’ technology and operations development efforts into a coordinated field test demonstration under representative (analog) planetary surface terrain conditions. The 2006 Desert RATS was the ninth RATS field test and was the largest, most systems-oriented, integrated field test to date with participants from seven NASA field centers, three industry partners, and two research organizations. Each week of the test, RATS addressed specific sets of objectives. The first week of field testing focused on Lunar surface science and in-situ resource utilization tasks.

During the first two weeks of September 2007, the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) Advanced Extravehicular Activity (AEVA) team led the field test portion of the 2007 Desert Research and Technology Studies (D-RATS) in the Flagstaff, AZ area. The Desert RATS field test activity is the year-long culmination of various individual science and advanced engineering discipline areas’ technology and operations development efforts into a coordinated field test demonstration. The field test is conducted under representative (analog) planetary surface terrain conditions. The 2007 Desert RATS was the tenth RATS field test and was the most focused test to date with participants from seven NASA field centers, a variety of NASA support contractors, and one other government agency. The main test objective was to demonstrate two operational concepts for lunar outpost activities/assembly to inform future Constellation Architecture Team (CAT) studies.

The National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) Advanced Extravehicular Activity (AEVA) Team, during the last two weeks of October 2008, led the field test portion of the 2008 Desert Research and Technology Studies (D-RATS) near Flagstaff, AZ. The D-RATS field test activity is the year-long culmination of the technology and operations development efforts of various individual science and advanced engineering discipline areas into a coordinated field test demonstration under representative (analog) planetary surface terrain conditions. The 2008 D-RATS, which was the eleventh RATS field test, was the most focused and successful test to date. It hosted participants from six NASA field centers, three research organizations, one university, and one other government agency.

The Advanced Extravehicular Activity (EVA) team of the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) led the Desert Research and Technology Study (RATS) in September 2004, at various test site locations near Flagstaff, Arizona. The Desert RATS is a two-week integrated remote field site test with team members from several NASA centers, universities, and industry partners participating. The overall objective of the RATS is to investigate and evaluate prototype advanced EVA exploration systems and technologies in order to develop well-defined requirements for the Vision for Space Exploration. This is accomplished by conducting simulated planetary surface exploration activities. Shirtsleeve subjects and subjects in pressurized space suits perform tasks such as geologic field mapping, rock sample collection and analysis, and communication infrastructure deployment.

The desert environment, its effect on the operation of military vehicles, and the procedures by which the U. S. Army insures that equipment is capable of successful operation in the desert are described. The recent history of military operations in desert areas is briefly reviewed to show the origins of the requirement for environmental testing, and tests performed by Yuma Proving Ground as a part of the Test and Evaluation Command's independent evaluation of Army vehicles are described. Criteria for successful operation in the desert and some of the problems experienced are discussed to show the need for careful attention to environmental factors early in the design of new vehicles.

Quickly determine how much desiccant you need with this free desiccant calculator. The tool provides desiccant unit estimations based on the internal air volume of an enclosure. Recommendations are made for three different desiccants.

This SAE Aerospace Standard (AS) describes the characteristics of a desiccant port installed through the flat wall of a shipping and storage container. With the cover removed, the desiccant port shall provide access to the interior of the container for installation and removal of desiccant.