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Energy Conversion Engineering Conference, 1997. IECEC-97., Proceedings of the 32nd Intersociety

Date July 27 1997-Aug. 1 1997

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  • Proceedings Of The Thirty-Second Intersociety Energy Conversion Engineering Conference [front matter]

    Page(s): i - vi
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    Freely Available from IEEE
  • Survey and critical review of recent innovative energy conversion technologies

    Page(s): 2283 - 2288 vol.4
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    A summary review is presented of the experiments, motors, generators, devices, and demonstrations that have been reported in the past several years to produce near-unity or over-unity operation. The concepts of free-energy, zero-point energy, and over-unity devices are not new, and many examples of such devices have been built within the last 100 years. Several researchers are reviewed and a few are selected for immediate interest and support. Whether new forms of potential energy can be demonstrated and successfully utilized within the near future for the ultimate benefit of the human race remains to be seen. View full abstract»

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  • A review of the Patterson Power Cell

    Page(s): 2289 - 2294 vol.4
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    An independent summary review is presented of the Patterson Power CellTM, as developed by Clean Energy Technologies. Information is drawn from publicly available information, and requested information and data from CETI. It is found that this cell seems to operate as advertized by CETI and that there is a very large amount of supportive documentation available in the public domain to support its operation and capabilities. The ability of such cells to neutralize alpha radiation is fairly well understood. An ability to neutralize gamma or other forms of radiation remains to be seen View full abstract»

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  • Solar photovoltaic as an energy source for India

    Page(s): 2328 - 2333 vol.4
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    Solar photovoltaic based power and energy systems are gaining recognition due to the availability and high solar insolation in most parts of India and the inherent advantage of direct conversion to power unlike a solar thermal system. Solar photovoltaic technology, its application in remote areas, its advantage as a stand alone system, environmentally friendly and inexhaustible source are some of the positive features of this wonderful source of nature. However, the limitations of day and night cycles and high costs in comparison to other sources of energy hinder its ready acceptance. More and more research is called for in the area of solar photovoltaics along with the discovery of alternative materials with higher efficiency of conversion, reduced panel areas per kW and effective, economic and durable storage systems for sustained production of power. This source alone, if costs can be reduced substantially, can meet the entire requirement of the country. Solar photovoltaics can also be utilised for bulk power for grid interconnected applications. It has a good scope for utilisation on the hybrid system, for pumping of drinking water and remote area power systems. This paper discusses all the features of the solar photovoltaic system, its cost comparison with other sources, its merits and demerits as of now, Government policy support, R&D efforts in India and strategies for commercialisation View full abstract»

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  • A magnetic bearing system design methodology and its application to a 50 Wh open core composite flywheel

    Page(s): 2306 - 2311 vol.4
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    In this paper, the authors describe a design methodology for magnetic bearing systems which has been successfully applied to the design of magnetic bearings for a variety of applications. The design of magnetic bearings for a 50 Wh open core flywheel is used to illustrate the concepts developed as part of the methodology View full abstract»

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  • Steady-state performance of a rotating miniature heat pipe

    Page(s): 2295 - 2301 vol.4
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    The operating principle of a rotating miniature heat pipe (RMHP) with a grooved inner wall surface is addressed. A mathematical model of the hydrodynamic performance of RMHPs is developed. A simple correlation for the friction coefficient of axial liquid flow including a vapor drag effect is proposed based on the numerical analysis of 2D laminar liquid flow in a groove. With the present model, the maximum performance and optimum liquid fill amount of RMHPs are predicted under various operating conditions. Influences of operating temperature, rotational speed and liquid-vapor interfacial shear stress on the maximum performance and optimum liquid fill amount are discussed. Pressure drops of the axial liquid flow and vapor flow are demonstrated View full abstract»

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  • A digital controlled solar array regulator employing the charge control

    Page(s): 2222 - 2227 vol.4
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    A microprocessor controlled solar array regulator (SAR) system is presented. The inner analog loops employing the charge current control scheme continuously regulate the solar array output power according to the reference value generated by the electrical control unit (ECU). The ECU consists of peak power tracking and a battery charge current regulation algorithm. Modeling, analysis and a design procedure of the inner loops and the system loop are presented, taking into account the interaction between the inner analog loops and the outer digital loops. Utilizing the inherent characteristics of the inner voltage and current loops, the system's dynamic performance and stability can be optimized up to the speed limit of the microprocessor View full abstract»

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  • Thermal analysis of paddy husk. II. Order of reaction and other kinetic parameters

    Page(s): 2322 - 2327 vol.4
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    This paper presents experimental data on the thermal degradation of paddy husk and cellulose in air, argon and a mixture of nitrogen and oxygen (95:5) at different linear heating rates. The data is used for the determination of kinetic parameters using different orders of reaction and an optimum order of reaction identified. The often used assumption of unity order of reaction under all circumstances is shown to have a limited validity View full abstract»

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  • Thermal analysis of paddy husk. I. Sensitivity of kinetic parameters to selection of stage transition points

    Page(s): 2316 - 2321 vol.4
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    Experimentally obtained TGA data on paddy husk and cellulose has been correlated using a two stage model. The data correlation is highly sensitive to the choice of the stage transition point. The effect of different stage transition points on the kinetic parameters is examined in this paper and an optimum stage transition point identified. The technique has also been tested on earlier published data and found to give satisfactory results. The systematic choice of the stage transition point should lead to greater uniformity and reliability in reported kinetic data View full abstract»

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  • Review and status of reported innovative energy conversion technologies, contrasted using a consistent R&D ranking scale

    Page(s): 2277 - 2282 vol.4
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    A summary review and status is presented of the experiments, motors, generators, devices and demonstrations that have been reported in the past several years to produce near-unity or over-unity operation. The concepts of free-energy, zero-point energy and over-unity devices are not new, and many examples of such devices have been built within the last 100 years. Several devices are reviewed and ranked by a consistent research, development and commercialization ranking scale. Those devices nearest to commercialization are identified and summarized. Whether new forms of potential energy can be demonstrated and successfully utilized within the near future for the ultimate benefit of the human race remains to be seen View full abstract»

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  • Numerical simulation of methane-air turbulent diffusion flames

    Page(s): 2351 - 2356 vol.4
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    This study deals with the numerical investigation of a chemically reacting methane gas jet which issues into a quiescent atmosphere. Assuming fuel-air mixing to be the rate controlling process (i.e. infinite chemical kinetics) the Shvab Zel'dovich formulation has been employed for analysing the turbulent diffusion flame characteristics. A transient FEM scheme in terms of the primitive variables (u, v, p) and the Shvab-Zel'dovich variables β1 and β2 has been implemented for studying the axisymmetric reacting jet problem. Galerkin's weighted residual approach with 4-noded elements has been adopted for spatial discretization. Numerical predictions for the mixing characteristics of the reacting jet have been carried out for various Reynolds numbers, and results have been obtained for the axial momentum decay, jet spread and entrained mass flow rate. The axial and radial variations of temperature and mass concentrations of fuel/oxidizer species have been predicted. The variation of flame height with Reynolds number is also obtained. The theoretical results have been validated against the experimental results available in the literature View full abstract»

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  • Combustion heated cold seal TEC [thermionic energy convertor]

    Page(s): 2264 - 2270 vol.4
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    This report discusses the concept of the combustion heated cold seal TEC (thermionic energy convertor). A cold seal TEC will be developed and tested, in which the rubber O-ring seal will electrically insulate the hot shell from the collector heat pipe. The cold seal TEC will use a noble gas+cesium as the working medium. In its cold state, the cesium will short circuit the emitter and the collector. During operation, the interelectrode space will be filled with cesium vapor. The upper part of the cold seal TEC will be filled with a noble gas. This noble gas will prevent the O-ring seal from being attacked by the cesium. The TEC output characteristics will be considerably improved by using electrode materials that were developed earlier in the course of an ECS-project for the development of low-temperature TEC electrodes View full abstract»

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  • A method for the analysis of high power battery designs

    Page(s): 2252 - 2257 vol.4
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    A spreadsheet model for the analysis of batteries of various types has been developed that permits the calculation of the size and performance characteristics of the battery based on its internal geometry and electrode/electrolyte material properties. The method accounts for most of the electrochemical mechanisms in both the anode and cathode without solving the governing partial differential equations. The spreadsheet calculations for a particular battery design are performed much like a battery test in that the C/3 capacity of the battery to a specified cut-off voltage is determined and then the pulse power capability at a given state-of-charge is determined by finding the maximum current density (A/cm2) for which the cell voltage equals a specified minimum value. For a multi-cell module, the module characteristics are calculated using the cell results and packaging input information. The spreadsheet model has been validated for existing lead-acid (Sonnenschein), nickel cadmium (Saft), and nickel metal hydride (Ovonic) batteries for which test data and internal geometry information are available. Various battery designs were then evaluated using the method to show how batteries having high power densities (greater than 500 W/kg) could be designed. The spreadsheet model permitted the determination of the critical design parameters for high power lead-acid, nickel cadmium, and nickel metal hydride batteries View full abstract»

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  • Spacecraft power management software for the new millennium

    Page(s): 2228 - 2230 vol.4
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    The Jet Propulsion Laboratory's (JPL's) New Millennium Program (NMP) is a proving ground for 21st Century spacecraft technologies. Chief among these technologies is the field of spacecraft automation. The NMP Deep Space One (DS1) mission will have the most sophisticated autonomous software ever flown on robotic spacecraft. An important element of this software is the power management system. Since power is a system resource, this software spans many mission and spacecraft systems. It must predict future spacecraft power generation, plan activities within expected power resources, query on-board navigation and attitude control systems for position and attitude information (which impact solar power generation), monitor and analyze power system state and health, and diagnose and respond to power system failures and emergencies. This paper describes the DS1 power management system and its role in the DS1 autonomy software View full abstract»

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  • Flywheel technology past, present, and 21st Century projections

    Page(s): 2312 - 2315 vol.4
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    This paper describes the present status of flywheel energy storage technology, or mechanical batteries, and discusses realistic future projections that are possible based on stronger composite materials and advancing technology. The origins and use of flywheel technology for mechanical energy storage began several 100 years ago and was developed throughout the Industrial Revolution. One of the first “modern” dissertations on the theoretical stress limitations of rotational disks (isotropic only) is the seminal work by Dr. A. Stodola whose first translation to English was made in 1917. The next big milestones were during the 1960s and 1970s when NASA sponsored programs proposed energy storage flywheels as possible primary sources for space missions. However, it was not until the 1980s when microelectronics, magnetic bearing systems and high power density motor-generators became enabling technologies. The next decade proved that a mechanical battery could surpass chemical batteries for many applications View full abstract»

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  • SCARLET development, fabrication, and testing for the Deep Space 1 spacecraft

    Page(s): 2237 - 2245 vol.4
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    An advanced version of “Solar Concentrator Arrays with Refractive Linear Element Technology” (SCARLET) is being assembled for use on the first NASA/JPL New Millennium spacecraft: Deep Space One (DS1). The array is scaled up from the first SCARLET array that was built for the METEOR satellite in 1995 and incorporates advanced technologies such as dual-junction solar cells and an improved structural design. Due to the failure of the Conestoga launch vehicle, this will be the first flight of a modular concentrator array. SCARLET will provide 2.6 kW to the DS1 spacecraft to be launched in July 1998 for a mission that includes fly-bys of the asteroid McAuliffe, Mars and the comet West-Kohoutek-Ikemura. This paper describes the SCARLET design, fabrication/assembly and testing program for the flight system View full abstract»

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  • Power and pyro subsystems for Mars Pathfinder

    Page(s): 2231 - 2236 vol.4
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    The power and pyro subsystem (PPS) for the Mars Pathfinder was designed to support the spacecraft activities during launch, cruise, entry and landing and Mars operation phases of the mission. The key design constraints were cost, volume and mass. The PPS consists of solar arrays, batteries and power electronics. This paper describes the Mars pathfinder mission, key requirements on the PPS, the PPS system architecture and a description of each element of the PPS system View full abstract»

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  • Performance evaluation of a gas turbine cycle with a pulse combustion system

    Page(s): 2258 - 2263 vol.4
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    This paper presents a comprehensive analysis of the effect of a pulse combustion system on the performance of a gas turbine cycle. The advantages of pulse combustors are numerous. The purpose of this paper, is to analyze theoretically this effect so that the resultant changes in performance can be estimated without experiment. In addition, this paper investigates the utilization of converting part of chemical energy of fuel into pressure energy in the combustion chamber of a gas turbine utilizing a pulse combustor. A computer code has been written to evaluate the cycle performance, thermodynamic characteristics of the cycle during operation as compared with a conventional cycle. The study describes the influence of the maximum possible pressure rise in combustion chamber, the heat addition ratio, maximum temperature and compressor pressure ratio on the performance parameters such as fuel consumption, net work output, excess air factor and thermal efficiency View full abstract»

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  • Pulsed high power generation system using a disk MHD generator driven by nonequilibrium plasma generator

    Page(s): 2271 - 2276 vol.4
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    The author propose a closed cycle disk MHD generator driven by a nonequilibrium plasma generator (NPG/CCDisk) system as an alternative for application as a portable-high performance pulsed power supply which could be applied for geophysical research, geological survey, earthquake prediction and other commercial and experimental power supplies. Performance prediction and design study of a disk generator for NPG system are carried out. The authors find that in order to demonstrate higher performance, detailed design of channel shape is necessary. A design study is also carried out based on the concept that local electron temperature is kept so as to locate the plasma in the stable regime. Enthalpy extraction of up to 40% and output power of 7.2 MW with the thermal input of 18 MWt are successfully expected. The effects of combustion product of alumina particle and residual oxygen on generator performance are studied. Results show that when alumina particle and oxygen concentration exceed a certain level, the output power suddenly decreases. Fortunately, possible alumina particle and residual oxygen concentration at the typical NPG burning conditions are found to be well below each critical level of power degradation. The main principle of this NPG/CCDisk concept is confirmed. Finally, the authors conclude that the proposed NPG/CCDisk system must provide a reliable and durable high performance pulsed power supply View full abstract»

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  • Technical standards and legal requirements for wind turbines: a global overview

    Page(s): 2338 - 2344 vol.4
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    Recent events and developments in the global wind energy scene relating to safety and the emergence of specific individual national technical criteria and standards like in India have raised the need for having an international standardisation and harmonisation for wind turbines. There have been attempts by the International Electrotechnical Commission (IEC) globally and European Union's European Wind Turbine Standards (EWTS) project regionally, to develop international standards for wind turbines. Some leading nations in wind energy development like Germany, Netherlands and Denmark in the Europe have their own national standards and policies. Other leading nations like the USA and India are moving towards having national legal and technical requirements. Against this backdrop, the paper examines the features of various national requirements for wind turbines existing in the leading countries viz. USA, Germany, India, Denmark and Netherlands. The initiatives towards international standardisation like the IEC initiative and the EWTS project are also examined. An attempt is also made to evaluate the need for such common international standards vis-a-vis individual national technical and legal requirements View full abstract»

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  • Analysis of DC/DC converters with resonant filters

    Page(s): 2217 - 2221 vol.4
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    Conventional DC/DC power converter topologies contain a single semiconductor switch, a diode and various arrangements of inductors and capacitors to filter the resulting waveforms into low ripple DC. The output or input voltage is limited to the rating of the semiconductor switch and diode. For high voltage performance, transformers are added to form forward, flyback or push-pull topologies. For high input voltages, semiconductor switches are arranged in an inverter bridge topology with a transformer to operate at higher voltages. Generally, conventional DC/DC power converters are limited to low voltage applications. The addition of a transformer to provide sufficient voltage gain adds significant weight to the converter. Series, parallel resonant circuits with dual bridge circuits can function like a DC/DC power converter with a transformer. Resonant converter topologies concepts have existed for the past 30 years. This paper presents a simplified generalized view of resonant circuits as π-filters and T-filters which give insight into improving circuit performance and developing new resonant topologies for bidirectional power flow View full abstract»

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  • Destruction of marine sewage using conventional engine technology

    Page(s): 2334 - 2337 vol.4
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    Ship operators are under mounting environmental pressure to reduce, and in certain cases totally eliminate, the discharge of waste into the sea. At the moment, beyond the twelve mile limit, untreated sewage can be legally discharged into the open oceans. For some types of waste, there is international nil-discharge legislation which prohibits any dumping in certain sea areas. In the future, sewage is likely to be identified as one of these nil-discharge waste materials. Thus, there may soon be a requirement for onboard sewage systems that are capable of meeting this requirement. In this paper, the novel concept of using marine diesel engines to thermally destroy sewage streams is considered. The main constituent of such effluents is water, about 90% and an appreciable amount of the solid content is combustible. As direct water injection is now an established technology for NOx reduction from marine diesel engines, it appears feasible, at least technically, to use such technology in sewage stream treatment. Preliminary estimates have shown that the sewage stream quantities produced onboard large marine vessels could be treated using the ships' existing diesel engines. The outline requirements for such marine diesel engines to be operated as sewage processors are discussed in this paper View full abstract»

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  • Cassini RTG acceptance test results and RTG performance on Galileo and Ulysses

    Page(s): 2211 - 2216 vol.4
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    Flight acceptance testing has been completed for the radioisotope thermoelectric generators (RTGs) to be used on the Cassini spacecraft which is scheduled for an October 6, 1997 launch to Saturn. The acceptance test program includes vibration tests, magnetic field measurements, mass properties (weight and c.g.) and a thermal vacuum test. This paper presents the thermal vacuum test results View full abstract»

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  • Sustainable energy: 2012-policy and legislation

    Page(s): 2345 - 2349 vol.4
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    Electricity demand in India is increasing at the rate of 7% per annum. This is the result of an increased rate of industrialisation, urbanisation and agricultural activities. At present, the energy and peaking shortages are about 8% and 19% respectively. These shortages can be supplemented by renewable energy sources. There are two kinds of energy generation and distribution systems-centralised and decentralised. The concept of a centralised system is harnessing energy at a centralised centre and then redistributing the same to a wide area around it. Power transmission losses, high investment on laying transmission lines and on repair and maintenance are some of the limitations of the centralised power generating systems. In India, centralised energy distribution systems are predominant and energy sources mostly conventional-70% through coal-fired thermal power plants. Not only is this system expensive in monetary terms, the environmental costs of generating conventional energy are also very high, when compared with nonconventional energy systems. Decentralised energy systems emerge from small-scale systems catering to the needs of small groups of people. This is especially applicable in remote rural areas where the cost of conventional energy systems would be higher and difficult to supply. Nonconventional solar, wind and biomass energy can be harnessed locally and distributed through both centralised and decentralised systems View full abstract»

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