Optimization of Free Piston Expander Based Organic Rankine Cycle

Thanks to its simple design, operational flexibility and potentially higher thermal efficiency at higher pressure ratios, the free piston expander (FPE) is gaining popularity and attention from researchers. A lot of work is expanded to implement the FPE concept in the organic Rankine cycle (ORC) for waste heat recovery. However, steady-state models that predict the efficiency and power output of FPEs under varying conditions are not available. The main objective of this work is to build a steady-state model to optimize the FPE-based, waste heat recovery cycle using a suitable working fluid. A thermodynamic analysis is carried out to match the unsteadiness of the FPE with the steady heat rejection, pressurization, and heat recovery of the ORC. Entropy before condensation and internal energy after constant volume filling is optimized, keeping the thermodynamic state of the fluid coming out of the heat exchanger fixed on the saturated vapor line. From optimized values, work output and efficiency for a specified condition (hot and cold source temperatures) are calculated. Targeted power output, maximum allowable piston velocity, and frequency are constrained by the system, from which the sizing of an FPE is derived. The sizing criteria provides a mean for the selection of the optimum working fluid. The analytical results show that the efficiency increases with the increasing expansion ratio up to a certain value, but however has a negative effect on specific power. Increasing the initial volume, before the filling of the FPE takes place, decreases both the efficiency and specific power and should be minimized for optimal operation. Optimum fluid selection is also carried out for two test cases with varying hot source temperatures and maximum piston velocity

Subsonic Ultra Green Aircraft Research

This Final Report summarizes the work accomplished by the Boeing Subsonic Ultra Green Aircraft Research (SUGAR) team in Phase 1, which includes the time period of October 2008 through March 2010. The team consisted of Boeing Research and Technology, Boeing Commercial Airplanes, General Electric, and Georgia Tech. The team completed the development of a comprehensive future scenario for world-wide commercial aviation, selected baseline and advanced configurations for detailed study, generated technology suites for each configuration, conducted detailed performance analysis, calculated noise and emissions, assessed technology risks, and developed technology roadmaps. Five concepts were evaluated in detail: 2008 baseline, N+3 reference, N+3 high span strut braced wing, N+3 gas turbine battery electric concept, and N+3 hybrid wing body. A wide portfolio of technologies was identified to address the NASA N+3 goals. Significant improvements in air traffic management, aerodynamics, materials and structures, aircraft systems, propulsion, and acoustics are needed. Recommendations for Phase 2 concept and technology projects have been identified

The time-dependent flow through throttle valves: a computational and experimental investigation

The automotive industry is, perhaps, and that is left open to debate, one of the most important engineering fields, and one which is increasingly influential on our everyday lives. Automotive engineering brings together all aspects of engineering knowledge to produce the one product that so many people have become dependent upon. The industry itself is vast and many tangents can be drawn from it, hence here we must define the area of interest to which this work relates. The initial concept for the work carried out stems from the passenger car industry; however, the work has more farreaching benefits and implications. As passenger vehicles become increasingly popular and increasingly advanced, so the need increases to understand more of the operation of all aspects of the vehicle. This work stems from a need to gain understanding of the flow of breather and blowby gases within an internal combustion engine (ICE) with the long-term aim of fully understanding the processes involved to enable improved engine design and reduced pollutant production. The latter is a significant driving force as legislation becomes more strict on the level of pollutants emitted from vehicles and engines. This work therefore not only reflects on passenger vehicles, but any other industry or product that uses ICEs

Bibliography of Lewis Research Center technical publications announced in 1986

This compilation of abstracts describes and indexes the technical reporting that resulted from the scientific and engineering work performed and managed by the Lewis Research Center in 1986. All the publications were announced in the 1986 issues of Scientific and Technical Aerospace Reports (STAR) and/or International Aerospace Abstracts (IAA). Included are research reports, journal articles, conference presentations, patents and patent applications, and theses

ECOS 2012

The 8-volume set contains the Proceedings of the 25th ECOS 2012 International Conference, Perugia, Italy, June 26th to June 29th, 2012. ECOS is an acronym for Efficiency, Cost, Optimization and Simulation (of energy conversion systems and processes), summarizing the topics covered in ECOS: Thermodynamics, Heat and Mass Transfer, Exergy and Second Law Analysis, Process Integration and Heat Exchanger Networks, Fluid Dynamics and Power Plant Components, Fuel Cells, Simulation of Energy Conversion Systems, Renewable Energies, Thermo-Economic Analysis and Optimisation, Combustion, Chemical Reactors, Carbon Capture and Sequestration, Building/Urban/Complex Energy Systems, Water Desalination and Use of Water Resources, Energy Systems- Environmental and Sustainability Issues, System Operation/ Control/Diagnosis and Prognosis, Industrial Ecology

The time-dependent flow through throttle valves : a computational and experimental investigation

The automotive industry is, perhaps, and that is left open to debate, one of the most important engineering fields, and one which is increasingly influential on our everyday lives. Automotive engineering brings together all aspects of engineering knowledge to produce the one product that so many people have become dependent upon. The industry itself is vast and many tangents can be drawn from it, hence here we must define the area of interest to which this work relates. The initial concept for the work carried out stems from the passenger car industry; however, the work has more farreaching benefits and implications. As passenger vehicles become increasingly popular and increasingly advanced, so the need increases to understand more of the operation of all aspects of the vehicle. This work stems from a need to gain understanding of the flow of breather and blowby gases within an internal combustion engine (ICE) with the long-term aim of fully understanding the processes involved to enable improved engine design and reduced pollutant production. The latter is a significant driving force as legislation becomes more strict on the level of pollutants emitted from vehicles and engines. This work therefore not only reflects on passenger vehicles, but any other industry or product that uses ICEs.EThOS - Electronic Theses Online ServiceJaguar Cars Ltd.GBUnited Kingdo

Crosscutting Technology Development at the Center for Advanced Separation Technologies

The U.S. is the largest producer of mining products in the world. In 2003, U.S. mining operations produced $57 billion worth of raw materials that contributed a total of$564 billion to the nation's wealth. Despite these contributions, the mining industry has not been well supported with research and development funds as compared to mining industries in other countries. To overcome this problem, the Center for Advanced Separation Technologies (CAST) was established to develop technologies that can be used by the U.S. mining industry to create new products, reduce production costs, and meet environmental regulations. Originally set up by Virginia Tech and West Virginia University, this endeavor has been expanded into a seven-university consortium -- Virginia Tech, West Virginia University, University of Kentucky, University of Utah, Montana Tech, New Mexico Tech and University of Nevada, Reno - that is supported through U.S. DOE Cooperative Agreement No. DE-FC26-02NT41607: Crosscutting Technology Development at the Center for Advanced Separation Technologies. Much of the research to be conducted with Cooperative Agreement funds will be longer-term, high-risk, basic research and will be carried out in five broad areas: (1) Solid-solid separation; (2) Solid-liquid separation; (3) Chemical/biological extraction; (4) Modeling and control; and (5) Environmental control. Distribution of funds is handled via competitive solicitation of research proposals through Site Coordinators at the seven member universities. These were first reviewed and ranked by a group of technical reviewers (selected primarily from industry). Based on these reviews, and an assessment of overall program requirements, the CAST Technical Committee made an initial selection/ranking of proposals and forwarded these to the DOE/NETL Project Officer for final review and approval. The successful projects are listed by category, along with brief abstracts of their aims and objectives