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In modern Diesel engine control strategies the guideline is to perform an efficient combustion control, mainly due to the increasing request to reduce pollutant emissions. Innovative control algorithms for optimal combustion positioning require the on-board evaluation of a large number of quantities. In order to perform closed-loop combustion control, one of the most important parameters to estimate on-board is MFB50, i.e. the angular position in which 50% of fuel mass burned within an engine cycle is reached. Furthermore, MFB50 allows determining the kind of combustion that takes place in the combustion chamber, therefore knowing such quantity is crucial for newly developed low temperature combustion applications (such as HCCI, HCLI, distinguished by very low NOx emissions). The aim of this work is to develop a virtual combustion sensor, that provides MFB50 estimated value as a function of quantities that can be monitored real-time by the Electronic Control Unit (ECU).

Natural gas is one of the alternative fuels that has received considerable attention in recent years. It is believed that spark ignition engines designed to operate on natural gas may be able to meet emissions regulations of the ULEV. Natural gas has some interesting characteristics which engine designers may be able to use successfully to meet impending regulations. However, concerns have been raised on the type of suitable catalyst for such engines and whether existing catalysts designed for gasoline fuel would meet natural gas engine requirements. The work described in this paper was conducted to assess suitability of some of the existing catalysts in lowering natural gas engine emissions.

This paper presents a discussion of the problems associated with the operation of pulsed plasma accelerators, and of the importance of specific impulse and energy conversion efficiency in the selection of a working engine. The accelerators are classified in terms of the manner in which the discharge takes place (direct or indirect) and also by their subsequent physical description (sheet or line). The development of the Plasma Pinch Engine at Republic is presented as an example of an accelerator in the development stages. The application of MHD to electrical generation for ground and space installation is described briefly with its associated problems (principally concerning materials). Finally a short description is given of the analytical work that has been done at Republic on the application of a magnetic field to a high power thermionic converter to increase its efficiency.

Coal fired MHD repowering is considered for the TVA Allen Steam Plant. The performance of the repowered plant is presented. Cost comparisons are made of the cost of repowering with MHD versus the cost of meeting similar standards by installing scrubbers and selective catalytic NOx reduction (SCNR). For repowering of a single 250 MWe unit, the costs favor scrubbing and SCNR. If one considers a single repowering of all three 250 MWe units by a single MHD topping cycle and boiler, MHD repowering is more economical. Environmental emissions from the repowered plant are estimated.

The commercial Modular High Temperature Gas-Cooled Reactor (MHTGR) achieves improved reactor safety performance and reliability by utilizing a completely passive natural convection cooling system called the RCCS to remove decay heat in the event that all active cooling systems fail to operate. For the highly improbable condition that the RCCS were to become non-functional following a reactor depressurization event, the plant would be forced to rely upon its inherent thermo-physical characteristics to reject decay heat to the surrounding earth and ambient environment. A computational heat transfer model was created to simulate such a scenario. Plant component temperature histories were computed over a period of 20 days into the event. The results clearly demonstrate the capability of the MHTGR to maintain core integrity and provide substantial lead time for taking corrective measures.

This paper discusses the Micco spin flight test program for the FAA Part 23 certification of the MAC-145A and the MAC-145B light single engine aircraft. The 145A was awarded FAA certification in January 2000 in the Utility Category (spins prohibited in operation use). Approximately 120 one turn spins were completed in the flight test program with no anomalies or safety incidents. The 145B, and increased power derivative of the 145A, was intended to be immediately certified in the Acrobatic Category which permits spins and acrobatic maneuvers. However, spin flight tests of approximately 210 spins revealed that the 145B, in its current configuration, could not meet the Acrobatic Category recovery criteria for multiple turn spins. It is now intended to certify the 145B in the Utility Category (spins prohibited) until further modifications and flight tests can be completed.

An overview of Digital Engine Controls is presented in light of the various phases required to develop an engine control microcomputer system. Topics include breadboarding techniques, vehicle mounted hardware, preproduction circuit sets, custom LSI circuit development and advanced integration. A brief review of depletion mode NMOS technology is presented along with details of a suitable family of 16 bit microprocessors, memories, and digital/analog input/output functions that can be implemented with LSI IC's to perform real time engine control. Finally, a development time table is presented which highlights program milestones in a two year development cycle.

THE rapid development of heavy-duty trucks and farm tractors has made it necessary for manufacturers of engines used in such automotive apparatus to face problems regarding which there is no past experience to fall back upon. The necessity in both types of engine for maximum strength in all parts carrying excessive loads constitutes a problem of great importance, but in addition to it are others of the proper utilization of fuels at present available, lubrication under excessive load conditions over long periods of time; and, of nearly as much importance, the relation of fuels to lubricants and the effect of fuels upon lubricants. Moreover, information is to be acquired regarding the value of prospective fuels as power producers, the effects they have upon engines, lubricants, etc., comparisons of cost and the like. The tests recorded in the paper were made in an endeavor to ascertain some of these unknown values.

The feeling that a truly heavy-duty engine for truck and tractor service was not available led the company represented by the authors to commence the development of an engine that would be capable of high speed as well as have ability to develop maximum horsepower and torque at low or medium speeds. Five specific requirements are stated for a tractor and three for a truck engine; the requirements of a universal truck and tractor engine are then specified under six headings. The special features of design of the engine developed are described in minute detail and illustrated by photographs and charts, seven definite features being mentioned as having been productive of the desired results. The testing apparatus is described and power and torque curves, a timing diagram and capacity curves of the water and oil-pumps are presented. Gasoline was used as fuel, although the engine is designed to use either gasoline or kerosene and is said to be adapted to the use of the heavier fuels.

When one looks at a situation from a distance, the probability of arriving at innovative solutions increases. Thus, when an industrial design student looks at the activity of eating and preparing food in space, the perception of the design problem starts with a lack of technical information, which makes it easier to break the conventional paradigm of how food is consumed in space. This is how Mikuy came to be. It is the outcome of a 15-week class project that culminated in the design of a crew food system for long duration orbital missions. Mikuy attempts to stimulate a harmonious environment on board the International Space Station (ISS), using food as the medium for enhancing crew cohesiveness and well being during missions. The paper starts with an overview of the development of space food. It is followed by assumptions that give the designer constraints to work with. The paper then goes on to propose ways in which to innovate the way food is prepared on board the ISS.

The prudent allocation of funds is always an issue with any government agency. This is especially true in the Department of Defense (DoD) due to its magnitude and heightened level of public scrutiny. Acquisition reform is an ongoing federal/commercial effort designed to save both government and industry money by permanently altering the manner in which the DoD solicits civilian contracts and products. A necessary first step in this reform is to revise outdated and obsolete military specifications and standards. This paper will examine federal policy regarding government specification reform and explore the implications of the policy to date. It will also speculate on the future of reform and address the bigger issue behind standards reform, civil-military integration.

Time Triggered networking technologies such as TTP (Time Triggered Protocol) are beginning to be used in critical aerospace applications such as flight controls. While TTP provides stringent specifications for determinism and fault tolerance, it does not define a physical layer. TTP's “de facto” physical layer, RS-485, includes shortcomings in a number of areas. These include a relatively low minimum transmitter voltage, low receiver threshold, along with a lack of specificity in a number of areas. The latter include bus signal levels, transmitter zero-crossing distortion and receiver zero-crossing tolerance, isolation method, terminal output noise, common mode and noise rejection, and input impedance. MIL-STD-1553, which has been deployed in flight and mission critical military applications for decades, defines a highly proven and robust physical layer. This paper presents MIL-STD-1553's physical layer as a candidate for use with TTP.

This paper describes the performance, physical and electrical characteristics of a series of new, very large scale integrated (VLSI) components. These devices fully support MIL-STD-1553 and a variety of computer/microprocesor based subsystems. A new low power transceiver, and protocol for Bus Controller, Remote Terminal and Monitor Modes of operation plus a computer I/O to a central, host processor is included. A discussion of the VLSI special technologies and features is covered. Features such a3 size, packaging options, radiation hardness, power and reliability considerations will be explored. The special programming options and subsystem interface considerations which facilitate a broad array of applications is thoroughly discussed.

This paper describes the nature and benefits of a newly released military standard that was developed in cooperation with the Aircraft Store Integration Subcommittee (AS-1B) of SAE's Avionics Systems Division. MIL-STD-3014, “Department of Defense Interface Standard for Mission Data Exchange Format” or “MiDEF,” is an open-systems standard for binary data files that transport mission-specific programming data for precision munitions, uninhabited combat vehicles, and similar systems. For system developers and mission capability architects, MiDEF's benefits are its independence from communications protocols, flexibility and adaptability, evolution-oriented design, compact file size, and ease of use. MiDEF is designed to support current military evolution toward network-centric warfare, time-sensitive targeting, and precision munitions.

Industry has expressed concern that the electromagnetic emission limits of MIL-STD-461 are incompatible with the AC voltage waveform distortion limits of MIL-STD-704. Previous industry studies have attempted to establish a correlation between MIL-STD-704 and MIL-STD-461 limits, but lacked the comprehensive analyses/data required for a meaningful document comparison. This paper presents the Navy's on-going effort to investigate equipment compatibility with MIL-STD-461 and MIL-STD-704 limits and to establish a correlation between the limits of MIL-STD-461 and MIL-STD-704. A preliminary investigation was conducted to review the requirements, test methods, and measurement relationships of specifications MIL-STD-461, MIL-STD-462, MIL-STD-704, and MIL-STD-1399.