Gary J. Morris

Kinetic studies of rapid oil shale pyrolysis: 2. Rapid pyrolysis of oil shales in a laminar-flow entrained reactor☆

Abstract Rapid pyrolysis of Kentucky New Albany shale was conducted in a laminar-flow entrained reactor (LFER) to obtain a fundamental understanding of thermal reactions, which occur during high-heating-rate retorting processes. The reactor configuration was designed to simplify operation and allow accurate modelling. Temperature characterization and flow visualization in the LFER were conducted to provide the data necessary to proceed with a kinetic study on the rapid pyrolysis of oil shale. The reactor with gas preheaters was constructed to achieve high particle heating rates and to feed oil shale fine particles generated from beneficiation. The rapid pyrolysis of raw and beneficiated oil shales was carried out in nitrogen at temperatures between 700 °C and 850 °C, with gas preheat temperatures up to 980 °C. For each temperature, the sampling probe was set at different positions along the length of the reactor tube to obtain different residence times. A pyrolysis kinetic model of LFER has been developed to calculate the particle heat-up rate and residence time under each set of conditions. Comparisons are presented to evaluate the effects of beneficiation, temperature and heating rate as well as residence time. The effects of particle size and gas environment on heat transfer rates and conversion yields were also studied, and the results were used to validate the heat transfer model and to evaluate the impact of devolatilization behaviour on shale combustion in a circulating fluidized-bed reactor.

One-Dimensional Modeling and Measurement of Pulsating Gas-Solid Flow in Tubes

Abstract Pulsating turbulent gas-particle flow in a circular tube is investigated by both experimental and numerical methods. In experiments, the ensemble averaged centerline gas and particle velocities ate measured by using laser Doppler anemometry. The amplitude and the frequency of pulsations are controlled via the diameter and the RPM of a rotating butterfly valve. It was found that significant variations could be obtained along the axial position in the amplitude and the phase of the fluid velocity deviation from its mean. Both the amplitude and the phase shift behavior was a function of the imposed pulsating frequency and amplitude. Particle velocity measurements showed that the slip velocities between the fluid and particles are dependent on frequency and position along the axial direction. The experiments are simulated using a one-dimensional transient model which consists of one-dimensional compressible flow equations in an Eulerian, and particle momentum equation in a Lagrangian frame of referen...

ACOUSTIC DETECTING AND LOCATING GAS PIPE LINE INFRINGEMENT

The power point presentation for the Natural Gas Technologies II Conference held on February 8-11, 2004 in Phoenix AZ, published the presentations made at the conference, therefore required all presenters to submit their presentation prior to November 2003. However in the remainder of year, significant new test data became available which were incorporated in the actual presentation made at the Natural Gas Technologies II Conference. The 6th progress report presents the updated actual slide show used during the paper presentation by Richard Guiler.

Exhaust Ducting Effects on Takeoff Lift Loss of Two-Dimensional Hypersonic Configuration

The National Aerospace Plane (NASP) configuration was designed to suit propulsion needs at hypersonic speeds. Like many hypersonic configurations, its lower fuselage surface was shaped to suit the propulsion system with an oblique shock compression ramp, scramjet combustion module, and a single expansion ramp nozzle. To minimize drag, the nose was very thin and the upper surface nearly flat. Previous work has shown this configuration produces poor low-speed and in-ground effect performance. This is characterized by significant power-on lift reduction that is intensified by ejector action while in-ground effect. The effects of exhaust ducting on the ground effect lift coefficients and surface pressure distributions of a two-dimensional model based on the NASP fuselage centerline geometry are demonstrated. A two-dimensional configuration was used in an attempt to separate the complex three-dimensional effects from the key problems with this configuration

Ground Effect Characteristics of a Two-Dimensional Hypersonic Configuration

The National Aerospace Plane (NASP) cone guration was designed to suit the propulsion needs at hypersonic speeds.Itslowerfuselagesurfaceformed thepropulsion system with an obliqueshock compression ramp, scramjet combustion module, and a single expansion ramp nozzle. To minimize drag, the nose was very thin and the upper surfacewas nearly e at. How each of these surfaces contribute to itspoor low-speed and ground effect performance is demonstrated. This poor performance is characterized by signie cant power-on lift reduction that is intensie ed by ejector action while in ground effect. The NASP aerodynamic characteristics were e rst measured on a threedimensionalmodelasfunctionsofangleofattack,groundproximity, andthrustcoefe cient. Then to separatethreedimensional effects from the key problems with this cone guration, the tests were repeated with a two-dimensional model based on the fuselage centerline geometry.

Frequency response of bodies with combined convective and radiative heat transfer

Abstract An analytical model for solving the problem of frequency response of bodies with combined convective and radiative heat transfer is presented. The issue of two conflicting types of conclusions existing in the literature regarding the effect of radiative heat transfer on the frequency response of bodies has been addressed and explained. It is shown how both types of conclusions are possible depending upon the type of assumptions involved in the solution of the problem or the scope and limitations of experimental observations.

Autoignition of Low-Heating Value Gases in a Direct-Injected Diesel Engine

Abstract The autoignition of gaseous mixtures representative of coal derived low-heating value fuels in a direct-injected diesel engine was theoretically investigated over a pressure and temperature ranges of 10 to 50 atm and 800 to 1000 K respectively- A computer model was validated with experimental data from an engine operated on direct injected synthetic coal gas. The computed results demonstrated the importance of the characteristic time associated with the chemical kinetics when compared to the fluid mixing. High gas temperatures resulting from high compression ratios, high boost, high inlet air temperatures or other ignition aids are needed to ignite these gases in a compression-ignition engine in a timely manner. The predicted sensitivity of the autoignition delay time to changes in the engine operating conditions was significant for temperature but almost negligible for pressures up to and slightly in excess of 30 atm

Ground-effect characteristics and centerline pressure distributions for a hypersonic configuration

Aircraft that operate at hypersonic speeds must adhere to stringent aerodynamic design restrictions. Typical designs incorporate complete integration of the fuselage and propulsion system. Unfortunately, these designs tend to perform poorly at subsonic speeds and demonstrate unfavorable propulsion/aerodynamic interactions when operated in ground effect for takeoff. Significant work has been done to quantify this interaction including pressure measurements using a two-dimensional model. This paper presents basic aerodynamic coefficients and centerline lower surface-pressure distributions that were measured on a three-dimensional hypersonic configuration of the National Aero-Space Plane.

OPERATING PROCEDURE FOR THE PORTABLE ACOUSTIC MONITORING PACKAGE (PAMP)

The Portable Acoustic Monitoring Package (PAMP) has been designed to record and monitor acoustic signals in high-pressure natural gas (NG) transmission lines. Of particular interest are the three acoustic signals associated with a pipeline fracture. The system is portable (less than 30 lbm) and can be used at all line pressures up to 1000 psig. The PAMP requires a shut-off valve equipped 1/2 inch NPT access port in the pipeline. It is fully functional over the typical pressure range found in the natural gas transmission pipelines in the West Virginia, Virginia, Pennsylvania, and Ohio areas. With the use of the PAMP, a full spectrum of acoustic signals can be recorded and defined in terms of acoustic energy in decibels. To detect natural gas pipeline infringements and leaks, the acoustic energy generated inside the line is monitored with a sensitive pressure-equalized microphone and a step function type {Delta}p transducer. The assembly is mounted on a 1000 psig pipe fitting-tree called the PAMP. The electronics required to record, store and analyze the data are described within this report in the format of an operating manual.

Design Aspects Of A New Material Wear Tester

Most material frictionhear testers are variations of the BOCLE@ tester. It uses a rotating or oscillating spindle, loaded down with a weight. The spindle has one or more 0.5 inch diameter balls at its end rubbing over a flat test sample. Wear depends on the inaterlal properties of contacting surfaces: ball(s) and flat test sample. The flat test sample is fixed inside a cup filled with lubricant. The ratio of drag force to contact force provides the friction coefficient. Wear is reported for either material, as weight loss rate, or rate of groove width increase. Wear depends on contact surfaces physical properties, contact pressure, velocity, lubricant and contact temperature. Problems associated with the BOCLE@ tester are vibrations caused by the rotating or oscillating weight on the spindle, d~fficulty in changing the spindle load and rapid changes in ball contact area and thus pressure. Two new material-wear testers have been developed at WVU. The first one was for testing bearing materials submerged in methanol. The second to test bearing materials submerged in liquid zinc. The sample geometry was selected for low cost, ease of wear measurement, and self-centering. A l-inch balllhemisphere was mounted at end of rotating spindle. The fixed sample has a narrow seat making a 45-degree contact angle with ball. It is mounted inside a three-inch diameter cup, filled with molten zinc. The cup is suspended from a disc floating on ball bearmgs to facilitate self-alignment between ball and seat and to measure friction torque. The assembly is supported on a rubber inner tube, to dampen vibrations and maintain constant load The load is adjusted by lowering the spindle. Only at very heavy loads, inertia weights are added to the cup holder to dampen rotational vibrations. This design provides constant pressure wear testing. The seat wear rate is measured optically. Transactions on Engineering Sciences vol 43,