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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 downwash of the prop-rotor blades of the Bell/Boeing V-22 “Osprey” in hover mode creates an undesirable negative lift on the wing of the aircraft. This downforce can be reduced through a number of methods. Neglecting all other effects, such as power requirements, this research investigated the feasibility of using circulation control, through blowing slots on the leading and trailing edge of the airfoil to reduce the wake profile under the wing. A model was built at West Virginia University (WVU) and tested in a Closed Loop Wind Tunnel. The airfoil was placed normal to the airflow using the tunnel air to simulate the vertical component of the downwash experienced in hover mode. The standard hover mode flap angle of 67 degrees was used throughout the testing covered in this paper. All of these tests were conducted at a free stream velocity of 59 fps, and the baseline downforce on the model was measured to be 5.45 lbs.

The basic design of a purely rotary motion engine has potentially many advantages over the conventional piston-crank internal combustion engine. Although only one rotary engine has been successfully placed into production, rotary mechanisms still show promise in the market place. A comprehensive review of rotary engine concepts is presented with an emphasis placed on the last 30 years. Suggestions are made as to where research concentrations should be placed to improve the progress of a rotary engine.

An electrochemical cell is presented which reduces NOx emissions from a vehicle fueled by dedicated natural gas. The cell is comprised of a honeycomb shaped ceramic which is chemically coated with an electrically conductive material in two distinct regions which serve as electrodes such that, with the application of a voltage potential, a cathode and anode are formed. As the exhaust gas flows through the inner channels of the cell, the electrochemical reduction of NOx at the cathode yields nitrogen gas and oxide ions. The nitrogen continues to flow through the cell while the oxide ions dissolve in the solid electrolyte. At the anodic zone, oxide ions are converted to oxygen gas. The pressure drop across the cell was experimentally measured to insure that the back pressure created by the cell does not create a significant reduction in the efficiency of the engine.

Corona discharge from a RF quarter wave coaxial cavity resonator is considered as a plasma ignition source for spark ignited (SI) internal combustion (IC) engines. The gaseous discharge processes associated with this device are analyzed using principles of gas kinetics and gaseous electronics, with assumed values for the electric field strength. Corona discharge occurs when the electric field shaped and concentrated by a single electrode exceeds the breakdown potential of the surrounding gas. Ambient electrons, naturally present due to ionizing radiation, drift in the direction of the externally applied field, gaining energy while undergoing elastic collisions with neutral molecules. After gaining sufficient energy they dissociate, excite, or ionize the neutral particles through inelastic collision, creating additional electrons. This process leads to avalanche electrical breakdown of the gas within about 10-8 sec.

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.

A finite-difference gas adsorption computer model for CO2, H2O, and N2 on zeolite 5A is discussed. It is part of an effort to predict results, via simulation, of changing a spacecraft CO2 removal system's operational configuration. The mathematical and numerical modeling approach, with emphasis on identification and independent verification of important adsorption physics, is described. The apparatus used to obtain single and multicomponent isotherms, and the subscale packed column bench test used to derive transfer coefficients and verify the model are described. The favorable comparison of simulation and test results show the potential for predictive capability with this modeling approach.

When designing the Oculus sensor platform, many safety issues such as designing fail safes, adapting to flying situations, and examining situations produced by exposure to real-world conditions were taken into consideration. When predicting maintenance issues, environmental conditions that the platform will have to encounter were assessed. A material that was lightweight and strong enough to withstand the harsh environmental conditions experienced outside the C-130 aircraft was needed. In addition to the material used, another issue addressed was the ability to repair the platform easily and efficiently. Normal operations expose the components to significant wear and tear, which requires the replacement of parts to maintain safe operations. Oculus was constructed to allow for component replacement without deconstruction of the entire platform. While environmental factors were a concern, mechanical design and functionality, along with safety, was vital to the project.

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.

Enhancing the capabilities of established airframes to meet expanded mission requirements is preferential to the design of specialized aircraft. The high cost associated with the research and development of a specialized aircraft platform has shifted the concentration towards the modification of existing aircraft to support multiple C4ISR missions. The recently developed Oculus sensor deployment system is one such example of this trend, providing a fully integrated aerial visual enhancement platform with multi-mission capabilities. This paper provides a short survey of the Oculus sensor pallet system and overviews some of the multiple guidelines used which ensure that various remote sensing technologies may be securely and simultaneously deployed.

The Federal Test Procedure (FTP) for heavy-duty engines requires the use of a full-flow tunnel based constant volume sampler (CVS). These are costly to build and maintain, and require a large workspace. A small portable micro-dilution system that could be used on-board, for measuring emissions of in-use, heavy-duty vehicles would be an inexpensive alternative. This paper presents the rationale behind the design of such a portable particulate matter measuring system. The presented micro-dilution tunnel operates on the same principle as a full-flow tunnel, however given the reduced size dilution ratios can be more easily controlled with the micro dilution system. The design targets dilution ratios of at least four to one, in accordance with the ISO 8178 requirements. The unique features of the micro-dilution system are the use of only a single pump and a porous sintered stainless steel tube for mixing dilution air and raw exhaust sample.

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 development of a standardized roll-on, roll-off (RoRo) sensor pallet system for a C-130 aircraft was conceived by the National Guard and the Counter Narco-Terrorism Technology Development Office to assist in counterdrug reconnaissance activities within the United States and surveillance and reconnaissance missions worldwide. West Virginia University was contracted to perform the design and development of this system because of their innovative design ideas. Before development, the design parameters were established by these two DoD agencies, their mission requirements and by the limitations of the C-130 aircraft. These limitations include using Commercial off the Shelf (COTS) and Government off the Shelf (GOTS) items when developing the system that must be universal on all C-130 aircrafts variants B thru H. Further design criteria are by the limitations of the C-130 aircraft and its existing mission requirements.

A comprehensive review of low-heat rejection engine concepts is presented. Areas examined include the materials being considered for these engines; fuels including coal; the effects of high temperature upon emissions; tribology with ceramics; exhaust heat utilization systems; and applications of these engines. Inconsistencies in the literature arc discussed.

The potential benefits of using advanced fiber-reinforced composites as an alternative to metallic alloys has been investigated for the design and fabrication of connecting rods in motion conversion mechanisms for internal combustion engines. Two types of mechanisms have been selected for this analysis: the common slider-crank mechanism and the new. Stiller-Smith Mechanism, in which the crankshaft is replaced by a floating gear system. An improved finite-element elastodynamic model, which includes the effects of longitudinal, bending and shear deformations, has been developed in order to quantify the relationships between the levels of bearing loads and vibrations of such mechanisms and the material design of their connecting-rods. An extensive parametric study has been conducted on the material system, the lay-up and the cross-sectional dimensions of elastic connecting rods, made of helically wound composite materials.

The Stiller-Smith Mechanism provides a unique approach in the use of the rotational characteristics of the cross-slider link of the elliptic trammel. Establishment of the research need and a historical development of the design concept are presented complete with a detailed kinematic analysis. Successful incorporation of the new mechanism is pictorially presented.

New high-tech materials which are anticipated to revolutionize the internal combustion engine are being created everyday. However, their actual utilization in existing engines has encountered numerous stumbling blocks. High piston sidewall forces and thermal stresses are some of the problems of primary concern. The Stiller-Smith Engine should provide an environment more conducive to the use of some of these materials. Absent from the Stiller-Smith Engine is a crankshaft, and thus a very different motion is observed. Since all parts in the Stiller-Smith Engine move in either linear or rotary fashion it is simple to balance. Additionally the use of linear connecting rod bearings changes the location of the sidewall forces thus providing an isolated combustion chamber more tolerant to brittle materials and potential adiabatic designs. Presented herein is the development of this new engine environment, from conceptualization to an outline of present and future research.