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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.

Previous studies have shown that using blowing slots can reduce the effects of the rotor downwash on the main wing of a tilt-rotor aircraft, particularly the V-22 Osprey. The current study investigates the placement and air velocity of the leading edge blowing slot for optimization of the download reduction. The realizable turbulent kinetic energy - rate of dissipation (rke) numerical model available in Fluent 6.2.12 was used to model the flow involved under the rotors and the subsequent downwash around the main wing. It was found that the leading edge blowing slot is most beneficial when it is placed just upwind of the separation point without blowing slots. In the current investigation the optimal configuration is found between 0 percent and 1 percent of the chord length.

Project Oculus is an in-flight deployable mechanical arm/pod system that will accommodate 500 pounds of sensor payload, developed for a C-130 military aircraft. The system is designed for use in counter narco-terrorism and surveillance applications by the Department of Defense and the National Guard [1]. A prototype of the system has been built and is in the testing/analysis phase. The purpose of this study was to analyze the actual stresses and strains in the critical areas found using previous Finite Element (FE) simulations and to ensure that acceptable safety requirements have been met. The system components tested will be redesigned, tested, and reconstructed in the case of unacceptable safety factors or if more reliable methods can be implemented. The system was built to be deployed and retracted in flight, to avoid causing any problems in take off and landing.

In this analysis the structural integrity of the rotational system of a standardized roll-on, roll-off sensor pallet system was authenticated. The driving force behind this analysis was to ensure the structural integrity of the system and to locate the areas with optimization potential. This process will ideally lead to the weight reduction of individual components thereby allowing for the transportation of greater cargo during flight. Scaling down of these excessive areas will also allow for a reduced production cost and an increase in efficiency of the system. The study was comprised of the failure susceptibility of the individual components of the system. The major results include the optimization potential of individual components, as well as strategically rating and categorizing the failure capability of the components.

The purpose of this study was to optimize the current design of the roll-on, roll-off sensor deployment system support arm for the C-130 Hercules. The Department of Defense (DOD) and the National Guard (NG) will be using these sensor pallet systems in a variety of command and control configurations for counter narco-terrorism applications along with several other applications. The original design for the sensor deployment arm will be drawn using CAD, and then a Finite Element Analysis will be modeled and analyzed using Pro/ENGINEER and Pro/MECHANICA. This will show the stress concentrations and the areas where weight can be saved. The most concerning variable will be the height of the mechanical arm attachment. By decreasing that height, and shortening the mechanical arm, the moments will decrease, and the required torque will be less.

Continuously variable transmissions promise to improve the performance and drivability of vehicles. The design and implementation of continuously variable transmissions for medium or large displacement (power) engines have been hampered by the power limitations of the belts. A continuously variable transmission with a power split design (CVPST) has been developed to minimize the loading on the belt while providing for increased power transfer compared to existing designs. To aid in the design and development of this CVPST, a simulator program has been developed. The simulator can be used to optimize the CVPST and to compare with other transmissions. Finally, an optimized CVPST design is presented.

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.

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.

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.

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.

The Stiller-Smith Mechanism employs a double cross-slider to convert linear reciprocating motion into rotational motion. It has previously been shown that a four-cylinder configuration utilizing this motion conversion device can be balanced in two dimensions. The inherent planar nature of this mechanism makes it possible to produce a compact, eight cylinder configuration for use as an internal combustion engine which is balanced in three dimensions. This paper develops and presents the necessary requirements for such a balanced engine. Relative merits of various configurations are discussed and analytical results of different balancing schemes are presented.

The Stiller-Smith Engine employs a non-standard gear train and as such requires a closer examination of the design and sizing of the gears. To accomplish this the motion of the Stiller-Smith gear train -will be compared to more familiar arrangements. The results of a kinematic and dynamic analysis will introduce the irregular forces that the gears are subjected to. The “floating” or “trammel” gear will be examined more closely, first stochastically and then with finite element analysis. This will pinpoint high stress concentrations on the gear and where they occur during the engine cycle, The configuration considered will be one with: an output shaft, negligible idler gear forces, and floating gear pins that are part of the connecting rods rather than the floating gear. Various loading techniques will be discussed with possible ramifications of each.

The Stiller-Smith mechanism is a new mechanism for the translation of linear motion into rotary motion, and has been considered as an alternative to the conventional slider-crank mechanism in the design of internal combustion engines and piston compressors. Piston motion differs between the two mechanisms, being perfectly sinusoidal for the Stiller-Smith case. Plots of dimensionless volume and volume rate-change are presented for one engine cycle. It is argued that the different motion is important when considering rate-based processes such as heat transfer to a cylinder wall and chemical kinetics during combustion. This paper also addresses the fact that a Stiller-Smith engine will be easier to configure for adiabatic operation, with many attendant benefits.