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It is estimated that operating continuously on a B20 fuel containing the current allowable ASTM specification limits for metal impurities in biodiesel could result in a doubling of ash exposure relative to lube-oil-derived ash. The purpose of this study was to determine if a fuel containing metals at the ASTM limits could cause adverse impacts on the performance and durability of diesel emission control systems. An accelerated durability test method was developed to determine the potential impact of these biodiesel impurities. The test program included engine testing with multiple DPF substrate types as well as DOC and SCR catalysts. The results showed no significant degradation in the thermo-mechanical properties of cordierite, aluminum titanate, or silicon carbide DPFs after exposure to 150,000 mile equivalent biodiesel ash and thermal aging. However, exposure of a cordierite DPF to 435,000 mile equivalent aging resulted in a 69% decrease in the thermal shock resistance parameter.

It is well known that the drilling industry is a diverse industry with huge power needs for drilling deep wells. This paper discusses the drilling industry in general and the future need for HT power electronics to enable such activities as tractor drive drilling of deep horizontal wells. The discussion is geared at applications for drilling within the earth at ambient temperatures of 150°C and above.

The continued availability of leaded specialty aviation gasolines remains as an item of crucial importance in the near-term future of general aviation; however, the development of new piston engines capable of operation with other transportation fuels available in large pools is considered an indispensable element in the long-range survival of the industry. This paper offers a road map that while allowing the continued utilization of the current fleet of piston aircraft, sets the stage for a transition to new piston powerplants and associated aircraft, compatible with widely available transportation fuels such as motor gasoline based aviation fuels for the lower and some medium performance aircraft, and aviation turbine fuels for the balance of medium and high performance airplanes.

An outer loop guidance architecture was designed to control autonomous aerial refueling mission from the trail aircraft side. The design utilized bank, yaw rate, velocity and climb rate commands implemented using a previously developed adaptive trajectory concept. The concept was based on position error feedback that was used to control trail aircraft overshoot and tracking about the lead aircraft refueling point. To demonstrate this application, an open loop linear trail aircraft model at a given flight condition was selected. Inner loop control laws were designed using Linear Quadratic Regulator feedback controller and Balanced Deviation theory. The outer loop guidance architecture was then added to implement the application. The performance of the system was then evaluated for a selected position error, and disturbance.

Estimation and prediction of residual life and reliability are serious concerns in life cycle management for aging structures. Laboratory testing replicating fatigue loading for a typical military aircraft wing skin was undertaken. Specimens were tested until their fatigue life expended reached 100% of the component fatigue life. Then, scanning electron microscopy was used to quantify the size and location of fatigue cracks within the high stress regions of simulated fastener holes. Distributions for crack size, nearest neighbor distances, and spatial location were characterized statistically in order to estimate residual life and to provide input for life cycle management. Insights into crack initiation and growth are also provided.

The ideal internal-combustion crankshaft engine would burn all the fuel near top center without detonation, then expand the whole charge until exhaust Both events are impossible with current piston engines. The Hydrocycle Rocket Piston Engine concept employs a free piston in the head of a two-stroke-cycle engine. Combustion between the crank piston and the free piston allows direct conversion of combustion fluid expansion to hydrostatic fluid flow and accumulator gas compression with perfect timing and minimum thermal and mechanical losses. An infinitely variable, radial hydrostatic motor gives the driver smooth, gas-cushioned acceleration and stepless performance. Maximum economy is attained since the driver is forced to run the engine at optimum minimum speed to match road load oadin all traffic conditions.

People who wear protective uniforms that inhibit evaporation of sweat can experience reduced productivity and even health risks when their bodies cannot cool themselves. This paper describes a new sweating manikin and a numerical model of the human thermoregulatory system that evaluates the thermal response of an individual to transient, non-uniform thermal environments. The physiological model of the human thermoregulatory system controls a thermal manikin, resulting in surface temperature distributions representative of the human body. For example, surface temperatures of the extremities are cooler than those of the torso and head. The manikin contains batteries, a water reservoir, and wireless communications and controls that enable it to operate as long as 2 hours without external connections. The manikin has 120 separately controlled heating and sweating zones that result in high resolution for surface temperature, heat flux, and sweating control.

This paper deals with a conceptual aircraft cargo loader “that can do everything” commonly referred to as The Super Loader. The Super Loader is intended for use at air terminals to transport loads such as palletized cargo, containers, wheeled vehicles, shelters, and airdrop platforms from the storage docks to the military and civil aircraft, and vice versa. The loader may be described as a self-propelled, air transportable (in a C-141, C-17, C-5) 60,000 lb lifting capacity, adjustable height vehicle that will load/off load all transport aircraft from a C-130 whose cargo deck is only 3 feet, 3 inches high to a B-747 whose main deck upper limit is about 18 feet high. The Super Loader must also service the lower lobes of wide-bodies and main decks of narrow-bodied aircraft like the DC-8 and B-707. In brief, this loader will be required to interface with both civil and military cargo systems, present and future.

Of the many research approaches investigated over the years to measure the lubrication properties of aviation turbine fuels, the Ball-on-Cylinder Lubricity Evaluator (BOCLE) has emerged as the most significant test. BOCLE was originally a lubricant research device modified for low viscosity jet fuel when the Air Force encountered fuel control problems in 1965 with JP-4. It proved to be capable of detecting the presence of additives such as corrosion inhibitors which improve boundary lubrication properties and also the absence of natural lubricity agents in highly refined jet fuel. The Coordinating Research Council carried out several programs to investigate test variables such as cylinder type, humidity control and load. A semi-automated version using Falex test rings has now been commercialized and is being used to test fuels from aircraft experiencing abnormal pump wear and fuel control hang-up.

A novel two stroke cycle diesel engine is evaluated as a general aviation aircraft powerplant. Two certificated spark-ignited gasoline reciprocating engines are also evaluated in the same aircraft. The evaluation of aircraft propulsion performance considered only the effects of altered powerplant parameters on the range of an aircraft having a fixed gross weight and payload cruising at a given lift/drag ratio. Thermodynamic analysis finds the diesel engine can have a sea level power rating exceeding the 10,000 foot cruise power requirement by 55% with nearly equal specific fuel consumption, a low engine speed and a modest cylinder pressure. It uses a single-stage, radial turbocharger without intercooling or auxiliary mechanical scavenging. The diesel engine can significantly increase the range of a particular airplane now powered by a certificated turboprop engine. The candidate gasoline engines could not equal the turboprop-powered aircraft performance.

Two-stage-to-orbit (TSTO) conceptual-level vehicle designs were evolved by the Lockheed-California Company in the mid-1960s. The purpose was to provide a vehicle-systems-level basis for assessing the payload performance potential of a new class of Stage 1 propulsion systems: combined-cycle airbreathing/rocket engines. TSTO configurations were also established as conventional all-rocket and all-airbreathing engine comparison cases. These vehicle designs and their operating characteristics, along with their orbital payload-delivery capabilities, are presented for consideration by today's space transportation systems planning community.

Efficient and accurate ordinary differential equation (ODE) solvers are necessary for powertrain and vehicle dynamics modeling. However, current commercial ODE solvers can be financially prohibitive, leading to a need for accessible, effective, open-source ODE solvers designed for powertrain modeling. Rust is a compiled programming language that has the potential to be used for fast and easy-to-use powertrain models, given its exceptional computational performance, robust package ecosystem, and short time required for modelers to become proficient. However, of the three commonly used (>3,000 downloads) packages in Rust with ODE solver capabilities, only one has more than four numerical methods implemented, and none are designed specifically for modeling physical systems. Therefore, the goal of the Differential Equation System Solver (DESS) was to implement accurate ODE solvers in Rust designed for the component-based problems often seen in powertrain modeling.