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There are 30 million people in remote, rural communities in China without access to electricity. The government of China has initiated an ongoing effort to provide constant, reliable power to these citizens. Renewable energy is being utilized to solve this problem, which necessitates the use of a storage medium for energy, because renewable energies (i.e. wind and/or solar power) are inherently intermittent, variable, and largely unpredictable. By storing excess energy when it is plentiful (for a maximum feasible time of two days) and distributing it to the community in times of scarcity, the intermittent power is effectively leveled and auxiliary power is provided. A high-inertia flywheel was designed for this application because of its simplicity, ease of maintenance, low cost, and reliability. This design addresses many problems including bearing losses, aerodynamic losses, and distribution losses. The proposed design consists of a six spoke layout with a large outer ring.

Significant environmental and economic benefit could be obtained if spark ignited (SI) engines could be made more efficient. Engine operation using leaner fuel air mixtures at higher power densities and pressures promise higher thermal efficiencies. Mixtures required for such operation are often difficult to ignite with traditional spark plugs. In pursuit of better ignition sources, this paper presents a high-level model of an alternative microwave plasma ignition source under development. In this publication, atmospheric measurements of a pulsed microwave ignitor are used to derive an empirical model that will allow for control and increased energy delivery to the device. The model accounts for a simplistic plasma formation delay, a drop in resonance frequency as a result of plasma formation, and a subsequent change in associated microwave reflection coefficient.

Current research has involved manipulating the ignition inside of the combustion chamber. It has been demonstrated that an RF plasma flame can be generated from microwaves in a Quarter Wave Coaxial Cavity Resonator (QWCCR). By using this method, it may become possible for researchers to improve combustion and ignition characteristics of a modern internal combustion engine. Filling a plasma cavity with an appropriate dielectric medium can both alter electromagnetic properties and provide a suitable protective barrier to the harsh condition inside of a combustion cylinder. It is the purpose of this paper is to investigate both the operating frequency and quality factor of dielectric-filled cavities, as well as to suggest dielectrics that would be suitable for such an application.

The Federal Test Procedure (FTP) for heavy-duty engines requires the use of a full-flow tunnel based constant volume sampler (CVS) which is costly to build and maintain, and requires a large workspace. A portable micro-dilution system that could be used for measuring on-board, in use emissions from heavy duty vehicles would be an inexpensive alternative compared to a full-flow CVS tunnel, as well as requiring significantly less workspace. This paper evaluates such a portable particulate matter measuring system. This micro-dilution tunnel operates on the same principle as a full-flow tunnel, however dilution ratios can be more easily controlled with the micro dilution system. The dilution ratios for the micro-dilution system were maintained at least four to one, as per ISO 8178 requirements, by measuring the mass flow rates of the dilution air and dilute exhaust.

The Quarter Wave Coaxial Cavity Resonator (QWCCR) plasma igniter is designed, from previous theoretical work, as an ignition source for an internal combustion engine. The present research has explored the implementation of the QWCCR into an internal combustion (IC) engine. The QWCCR design parameters of inner conductor length, loop geometry, and loop position were varied for two igniters of differing operating frequency. Variations of the QWCCR radio frequency (RF) parameters, as a function of engine geometry, were studied by placing the igniter in a combustion chamber and manually varying the crank position. Three identical igniters were fitted with dielectric inserts and the parameters were studied before and after ignition was sustained in a twin-cylinder engine. Optimal resonator geometries were determined. Radio frequency parameter invariance was found with respect to crank angle and piston distance. The first successful IC engine ignition using a QWCCR was achieved.

A quarter-wave radio frequency coaxial cavity plasma ignitor can be used to generate a combustion-initiating energy source in an internal combustion engine. This paper outlines research results on the development of such an ignitor. The system, which operates in the 820 - 900 MHz frequency range, uses a high Q quarter-wave cavity that generates plasma when resonating. Pressure testing has shown that the device can generate plasmas at spark ignition compression pressures. A resonator operating at these frequencies has been attached to a static combustion chamber and modeled numerically in order to determine the operational characteristics of the device in a combustion chamber.

A complete three-dimensional thermal finite element analysis has been performed for the Beta version of an axial vane rotary engine. This work investigated the effects of the heat flow for two different geometric designs (kinematic inversions): rotor turning with vane turning and cams turning with a non-rotating vane. The output from a modified zero dimensional combustion code was used to establish the thermal boundary conditions in the finite element model. An iterative procedure between the thermal finite element model and the zero dimensional code was used to obtain the component wall temperature profile. Updating the combustion model wall temperature resulted in different thermal characteristics than those from the constant wall temperature solution. The thermal analysis provided a quantitative comparison of the different geometric versions of the engine, showing where improvements must be made.

It has been proposed that an automated remote color inspection of automobile body panels is possible with a reasonably precise color measurement. This paper outlines a test of a new 3D color measurement technology as applied to this task and presents the results of the first test. A camera is set up several feet away from a car body; a 3D orientation measuring system takes both 3D and color data from the car. The raw data is presented as a set of 3D graphs; the geometry-corrected data is also provided. Statistical analysis is presented to indicate system precision.

A family of transmission systems based on a “Planetary Gear - CVT” mechanism is presented here. The systems considered consist of two compound planetary gear trains connected through a CVT pulley system to provide the power/torque split and recirculation function, without the use of additional clutches and/or chain drives. A two degree of freedom system results in which one of the degrees of freedom is directly related to the CVT ratio. The mechanisms considered here combine the gear reduction function of compound planetary gear trains with the continuously variable trans- used as a circulating power control unit. The kinematics and dynamics of this family of systems is presented with emphasis on the belt forces, torques on the various shafts and the overall input/output velocity ratios through the CVT ratio span. Then a parametric analysis is conducted to characterize the effect of the various functional ratios and parameters of the system in terms of the overall performance.

In this paper, a new method for the hydro-dynamic analysis of a sliding cylinder in a fully lubricated parallel track is presented. The method is an extension of Booker's “Mobility Method” (developed for cylindrical journal bearings) to the case of sliding cylinders, in which the clearance between the track and the cylinder, the viscosity of the lubricant, the radius and length of the pin, the sliding velocity and the applied transverse load determine the hydrodynamic behavior of the cylinder. In the Rand Cam™ Engine [1]*, the axicycloidal motion of vanes is driven by a rotor and a cylindrical cam, and one of the alternative designs to provide this function is based on a cylindrical pin sliding within a track which follows the profile of the motion of the main cams of the engine. This function is very important for the engine, since it separates the load bearing function from the sealing function left to the apex-like seals.

Analysis of two types of bearings has been performed for the rotor shaft of the Rand Cam™ engine. Rolling element bearings and a combination of journal and thrust bearings for selected engine configurations have been considered. The engine configurations consist of four, five, six, seven, and eight vanes. The bearing geometry and orientation was also addressed. This analysis is crucial due to the potentially large axial loading on the bearings and the need for the bearing arrangement to be compact and reliable. An emphasis was placed on the combination of fluctuating axial and radial loads and the resulting effect upon the bearings. Tapered roller bearings were found to be effective. However, a combination of journal and thrust bearings is a more compact bearing arrangement for this application. The eight vane configuration is the most desirable configuration based upon the bearing analysis.

The Rand-Cam engine is a positive displacement machine, operating on a four stroke cycle, which consists of a rotor with multiple axial vanes forming combustion chambers as the rotor and vanes rotate in a cam shaped housing. The cam housing, consisting of two “half-housings” or stators, contains a toroidal trough of varying depth machined into each stator. The two stators are phased so that the shallowest point on one trough corresponds to the deepest on the other. A set of six vanes, able to move axially through machined holes in the rotor, traverses the troughs creating six captured zones per side. These zones vary in volume with rotor rotation. Since each trough has two deep sections and two shallow sections with ramps in between, full four stroke operation is obtained between each pair of vanes in each trough, corresponding to twelve power “strokes” per revolution.

The Rand Cam engine is a novel design which avoids the use of pistons in favor of a cavity of varying size and shape. A set of vanes protrudes from a rotor into a circular trough in a stator. The vanes seal to the walls and base of the trough, which is of varying depth, and progress around the trough with rotation of the rotor. These vanes therefore pass through the rotor and are constrained to move parallel to the rotational axis. Intake and exhaust processes occur through ports in the stator wall which are revealed by the passing vanes. Advantages of the basic design include an absence of valves, reduction in reciprocating masses, presence of an integral flywheel in the rotor and strong fluid movement akin a swirl induced by the relative velocity between the rotor and stator.

In this paper an approach is presented for the system parameterization and synthesis of a Rand-Cam® Engine configuration based on an axial-cylindrical cam driven mechanism. This engine consists of a stationary axial-cylindrical cam on which axially moving pistons (vanes) sweep around the cam as they are driven by the rotor, providing the volume displacement as the rotor delivers the rotary output torque directly to the shaft. It has been documented that this engine configuration has some unique features that make it particularly suitable for high power to weight ratio applications. The modeling strategy makes use of higher order curve and surface modeling techniques and object modeling approaches based on profile extruding, blending operations and constructive solid geometry. Some of the resulting models are further used for finite element engineering analysis through a programmatic logic built into the parameterized general model.

This paper describes a Radio Frequency (RF) plasma ignitor concept intended for application to internal combustion engines. This system features a high Q quarter-wave coaxial cavity resonator, of simple construction, serving as a tuning element in the RF power supply, a voltage magnifier, and a discharge device attached to the combustion chamber. The resonator is filled with a dielectric and open at the discharge end. The center conductor is terminated with a revolute solid capacitive electrode which concentrates the associated electric field. This non-uniform electric field within the air/fuel mixture creates a corona discharge plasma which is excited at the RF operating frequency and the resulting ionic species recombine to initiate combustion. The RF excitation, relative to DC, reduces breakdown voltage and electrode degradation.

The recent oil crisis has once again emphasized the need to develop both fuel efficient engines and alternately fueled engines, particularly for automotive applications. Engines which burn coal or coal pyrolysis products are attractive, but ignition delay and metal erosion problems continue to limit high speed operation of such engines. Further, the throttled spark ignition engine often used with methanol and natural gas does not prove an efficient or tolerant device for the combustion of a wide range of fuel. Therefore, an novel approach must be taken in order to achieve the efficient and flexible operation of such an engine. A novel design of a fuel tolerant engine suitable for burning coal fuels separates the combustion from the piston in order to have more careful flame control and to exclude the particulate matter from the engine's piston rings.

The unique shape of cruciform engines provides an alternative to the typical in-line or “V-shaped” engines. The planar nature of the mechanism provides either a low profile or thin engine with the ability to stack many 4 cylinder banks into a compact large engine. The sinusoidal motion inherent in this mechanism provides unique balancing aspects which ultimately further reduce the size of the power plant. The compact cruciform shape lends itself to applications in portable hydraulic pumps, compressors, hydraulic motors, internal combustion engines, etc.

Balancing to date, of the Stiller-Smith Mechanism, has been for a symmetric configuration. If two pistons are moved closer to the center of the engine to minimize spatial requirements and also reduce weight, then the mass center of the inner mechanism no longer travels in a circle about the center of the engine. It is shown how the overall balancing of the engine is not compromised using the example of a small 8-cylinder engine. The effects of the non-symmetry on the performance of the linear bearing is presented and the resulting additional engineering concerns are discussed.

The development of a mathematical model of StillerSmith Mechanism for the application of a 4-cylinder plunger pump system is presented. The magnitude and direction of the internal dynamic load are obtained by solving a set of equations using the overall geometric parameters, prescribed motions, inertia distribution, and applied torques on the system. The simulation presented here yields the history of the internal loads, which are then normalized with respect to the required peak output load on the plungers, through an entire rotary cycle. The approach allows for the development of further design criteria through parametric sensitivity studies.

The Scotch yoke in its various forms and inversions has received considerable attention as possible alternatives to the slider-crank for internal combustion engine use. As a recent entry, the Stiller-Smith Mechanism has shown promise as being a viable and strong option. In this study emphasis was placed on comparing the number and similarity of mechanism components and the balancing aspects of these components, implications of component and linkage motions, the severity of loading experienced by similar bearing surfaces within the engines, and some of the friction losses associated with these new motions. It was found that the Stiller-Smith Engine has significantly fewer moving parts. It was also found that journal bearings in the slider-crank engine were more severely loaded than those in the Stiller-Smith Engine. The linear reciprocating bearings in the Stiller-Smith Engine were more heavily loaded than the slider-crank piston skirts.