Design and evaluation of fluidized bed heat recovery for diesel engine systems

The potential of utilizing fluidized bed heat exchangers in place of conventional counter-flow heat exchangers for heat recovery from adiabatic diesel engine exhaust gas streams was studied. Fluidized bed heat recovery systems were evaluated in three different heavy duty transport applications: (1) heavy duty diesel truck; (2) diesel locomotives; and (3) diesel marine pushboat. The three applications are characterized by differences in overall power output and annual utilization. For each application, the exhaust gas source is a turbocharged-adiabatic diesel core. Representative subposed exhaust gas heat utilization power cycles were selected for conceptual design efforts including design layouts and performance estimates for the fluidized bed heat recovery heat exchangers. The selected power cycles were: organic rankine with RC-1 working fluid, turbocompound power turbine with steam injection, and stirling engine. Fuel economy improvement predictions are used in conjunction with capital cost estimates and fuel price data to determine payback times for the various cases

Wind-Diesel Systems in Alaska: A Preliminary Analysis

Most remote rural communities in Alaska use diesel to generate electricity. But the recent rapid development of a worldwide commercial wind industry, along with the rise in diesel fuel prices, has increased interest in wind power in rural Alaska—both to reduce energy costs and to provide local, renewable, sustainable energy. Wind is abundant in Alaska, and a growing number of rural communities are building winddiesel systems, integrating wind into isolated diesel power plants. These systems have moved from the initial demonstration phase a decade ago toward a technology available for many communities. Even in places that have not yet added wind, some rural utilities are planning for the possibility. For example, Alaska Village Electric Cooperative (AVEC) has committed to making new diesel power plants “wind ready” by designing its electrical systems so that wind turbines can be incorporated in the future without major reconfiguration. But it is not clear under what rural Alaska conditions wind-diesel systems are more economical than conventional diesel plant operations. The Alaska Energy Authority asked the Institute of Social and Economic Research (ISER) and the Alaska Center for Energy and Power (ACEP) to assess the performance of existing rural wind-diesel systems. We analyzed data available for existing wind-diesel systems as of spring 2010. Keep in mind that our analysis is preliminary; most rural wind-diesel systems are very new, and more time is needed to evaluate them fairly. Only three wind systems (Kotzebue, Wales, and Saint Paul Island) have been operating for more than a few years. Initial funding for the Kotzebue and Wales projects came from the U.S. Department of Energy, which funds research but does not subsidize utility operations. These early projects, built in the late 1990s, faced problems but demonstrated there is hardware that can operate in arctic environments. The Saint Paul village corporation funded the system on the island; it provides power for an industrial complex and airport the corporation owns. It is a high-performing system, and the most successful of the early demonstration systems, as measured by its capacity factor. However, it should be noted that both the Kotzebue and Wales systems have provided valuable experiences and lessons learned while integrating wind on a community-scale grid. Beginning in 2004, the Denali Commission funded projects in five communities (Selawik, Hooper Bay, Kasigluk, Savoonga, and Toksook Bay). In 2008, the Alaska Legislature created the Renewable Energy Fund, a competitive program intended to invest in renewable energy. That fund, which is administered by the Alaska Energy Authority, paid for construction of six projects listed as completed in spring 2010.Alaska Center for Energy and Power Alaska Energy Authority National Renewable Energy Laboratory Denali Commission AlaskaDefinitions / Executive Summary / Introduction / Alaska Wind-Diesel Systems / Technical Data Collection / Economic Analysis / Performance Analysis / Case Studies / Lessons Learned / Wind-Diesel Research Needs / Wind-Energy Financing Options / Reference

Engine performance of a single cylinder direct injection diesel engine fuelled with blends of Jatropha Curcas oil and stardard diesel fuel

Blends of Jatropha Curcas oil and standard diesel fuel were evaluated (without pre-heating). The engine tests for the blends were performed in a Petter single cylinder direct injection diesel engine under steady state conditions at high loads. Engine speeds between 1300-1700 rpm were selected for the engine tests. Torque, power output, specific fuel consumption, in cylinder pressure, ignition delay, rate of heat released and exhaust composition were evaluated. The tested blends between 10-20% of oil shown lower effective torque and power output joint to a higher specific fuel consumption related to the lower heating value of Jatropha oil compared to diesel fuel. Lower pressure peaks and rates or pressure rises were observed when Jatropha blends are used. A decrease in the rate of heat released and shorter ignition delay were observed for the blends. Decreases in HC and CO emissions were observed for blends compared to diesel fuel. Both alternatives assessed shown that the differences observed compared to diesel fuel, can be partially restored with engines regulation. The use of Jatropha oil in order to be a partial or full alternative to the use of diesel fuel for energy production was achieved

Assessment of alternative power sources for mobile mining machinery

Alternative mobile power sources for mining applications were assessed. A wide variety of heat engines and energy systems was examined as potential alternatives to presently used power systems. The present mobile power systems are electrical trailing cable, electrical battery, and diesel - with diesel being largely limited in the United States to noncoal mines. Each candidate power source was evaluated for the following requirements: (1) ability to achieve the duty cycle; (2) ability to meet Government regulations; (3) availability (production readiness); (4) market availability; and (5) packaging capability. Screening reduced the list of candidates to the following power sources: diesel, stirling, gas turbine, rankine (steam), advanced electric (batteries), mechanical energy storage (flywheel), and use of hydrogen evolved from metal hydrides. This list of candidates is divided into two classes of alternative power sources for mining applications, heat engines and energy storage systems

Sizing and Energy Management of a Hybrid Locomotive Based on Flywheel and Accumulators

The French National Railways Company (SNCF) is interested in the design of a hybrid locomotive based on various storage devices (accumulator, flywheel, and ultracapacitor) and fed by a diesel generator. This paper particularly deals with the integration of a flywheel device as a storage element with a reduced-power diesel generator and accumulators on the hybrid locomotive. First, a power flow model of energy-storage elements (flywheel and accumulator) is developed to achieve the design of the whole traction system. Then, two energy-management strategies based on a frequency approach are proposed. The first strategy led us to a bad exploitation of the flywheel, whereas the second strategy provides an optimal sizing of the storage device. Finally, a comparative study of the proposed structure with a flywheel and the existing structure of the locomotive (diesel generator, accumulators, and ultracapacitors) is presented

PTO performance and NOx emissions with D2, B20, and B100 fuels in a John Deere 3203 compact tractor

Tests were conducted in fall 2006 on a John Deere 3203 diesel tractor to determine differences in specific fuel consumption, power take-off (PTO) torque, PTO power, thermal efficiency, and oxides of nitrogen (NOx) emissions between No. 2 diesel (D2), 20% biodiesel (B20), and 100% biodiesel (B100). Four 1-hour tests were conducted on each fuel. The results indicated no statistically significant differences (p≤.05) between D2 or B20 on any variable of interest. However, B100 resulted in significantly (p≤.05) increased, specific fuel consumption and thermal efficiency and decreased PTO torque and PTO power over both D2 and B20. These data suggest that farmers could switch from D2 to B20 without any performance losses, but a switch to B100 would result in the use of more fuel and a loss of power and torque

Human Perception of Diesel Engine Idle Vibration

While the human perception of diesel engine noise has been the subject of numerous studies, the perception of the vibrational disturbance reaching the driver has not previously been investigated. This contribution presents the results of a recent research study performed at Sheffield University which analysed the nature of diesel engine idle, and modelled the associated human growth function. The results have shown that the largest component of diesel idle irregularity arriving at the steering wheel is amplitude modulation of the firing frequency and that the human subjective response grows with a power exponent greater than 1.0 for modulation values greater than 0.2