bluuebunny/crossref_metadata_2025 huggingface dataset:
Making a Clean Getaway
Authors: Sharke Paul
Published: July 2018

This article reviews the battery-powered electric vehicles that are forming a symbiotic relationship with commuter rail. Priced at around $6000, the electric vehicles make little sense for someone who has to get somewhere, when a full-fledged automobile can be had for twice that without any inherent restrictions on use, safety, and range. Perhaps retirees, with eyesight failing and reactions slowing, might be safer in such severely throttled cars. Think City drivers will have to bring their cars to the dealer about every 3,000 miles to have the equivalent of an oil change performed on the battery. The car’s nicad batteries are unsealed, unlike those powering calculators and electric drills, and so they need periodic watering. The average commuter probably is not ready to trade in the well-worn station car for a fancy golf cart, but the little electric cars may just warrant a second look from at least some of the great mass of bleary-eyed riders.
Where on Earth?
Authors: Wicks Frank
Published: July 2018

This article discusses how global positioning system (GPS) provides guidance for a new generation of unmanned surveillance aircraft. Traditional methods of surveying, for example, require benchmarks of known coordinates, followed by a sequential process of measuring angles and distances to calculate the coordinates of any other point. A GPS receiver uses satellites for benchmarks and rapidly processes timed signals into precise values of longitude, latitude, and elevation. GPS-based air traffic control is just beginning to be realized. GPS may also have profound consequences beyond those that can now be identified. Humans have only recently had access to portable and affordable clocks to measure time. Originally a tool for the military, the GPS now provides us with a device to extend the measurements into the three dimensions of space. More unintended consequences for the human condition are quite possible in the future.
Teamwork with the Next Generation
Authors: Smith Emily M.
Published: July 2018

This article discusses about Nightline, a robotics competition in which teams of students and engineers built robots that competed against each other in a sports-style event known as FIRST (For Inspiration and Recognition of Science and Technology). Creativity, communication, project management, partnerships, and a fundamental re-energizing of the engineering spirit are among the benefits that engineers and their supervisors describe as side effects of their involvement. While access to a future employee pool may be the reason that many organizations decide to get involved with FIRST, those side benefits are the reason most of them continue to participate. In many respects, FIRST has been turning out to be a fountain of youth. When hiring engineers, defense contractors have the added hurdle of getting their employees security clearance.
Transition Engineering
Authors: Marshall Donald J.
Published: July 2018

This article focuses on transition engineering that is in demand throughout Eastern Europe and the former Soviet Union, where transition of economic life started more than a decade ago. The larger companies had access to consulting resources of international firms to guide them in meeting their new responsibilities. But the smaller firms—from a few employees to several thousand—did not have the money to buy such advice. USAID stepped in to help with a series of programs using volunteer advisors, coordinated by local offices in the newly independent states. In the former Soviet Union, USAID programs seek to fill the void created by a lack of experienced managers and sufficient sources of newly trained personnel, by providing advisors with industry experience and necessary relevant skills.
How Does Your Fluid Flow?
Authors: Thilmany Jean
Published: July 2018

This article reviews the method of analyzing fluid flow in structures and designs, which is enjoying a burst of interest. Twenty years later, manufacturers across a myriad of industries are licensing the technology from a pool of vendors who now market computational fluid dynamics (CFD) packages of many stripes. Engineers use CFD to predict how fluids will flow and to predict the quantitative effects of the fluid on the solids with which they are in contact. Airflow is commonly studied with the software. Many mechanical engineers do not need access to all the bells and whistles an advanced CFD program can provide. Advanced analysis programs are usually the purview of a user trained on a particular CFD package. Engineers used CFD to determine how to best position the fans so that air flowed inside the refrigerator and the freezer in the most efficient way. After studying fluid flow simulations, they made prototypes of the most promising modeled designs to see if the prototypes matched CFD simulation results.
Harnessing the Void
Authors: Woods Robert O.
Published: July 2018

This article discusses that it frequently happens that the individual getting the credit for an invention is not the real innovator, but rather the person who was most successful in reducing an idea to practice. The Newcomen engine was staggeringly inefficient by today’s standards, but it was a commercial success for a time because it was the only practical alternative to pumps powered by horses. The aspect of a typical Newcomen engine that is most eccentric from a modern point of view is that it did not work using steam pressure at all. In the Newcomen cycle, steam was admitted to a cylinder and then condensed by injecting a water spray. One of Newcomen’s greatest contributions was to develop mechanisms to perform his cycle automatically. Early versions of his engine involved manually manipulated valves. This was a slow operation and provided an opportunity for disastrous errors; it clearly indicated a need for mechanical actuators.
The Next Century of Air Power
Authors: Nielsen Paul D. , Noor Ahmed K. , Venneri Samuel L.
Published: July 2018

The US Air Force has been pursuing the transformation of air and space power through development of technologies that yield new capabilities and by adopting novel operational concepts that enhance our ability to achieve desired military effects. Maturing a comprehensive set of technologies is the mission of the Air Force Research Laboratory. The transformation includes migrating military capabilities to unmanned platforms for a wide range of air applications and developing new directed energy capabilities, which produce effects on the battlefield ranging from the traditional destruction of enemy equipment to the revolutionary non-lethal, non-destructive stopping of advancing enemy troops. Vehicles being planned at the Air Force Research Laboratory include unmanned planes for surveillance and reconnaissance. Combat operations of the future may see officers giving commands to fleets of unmanned vehicles that are able to carry out orders on their own. Although precision munitions are smaller, more precise, and more autonomous, weapons using directed energy are beginning to emerge.
Remember the Adding Machine
Authors: Winters Jeffrey
Published: July 2018

This article illustrates research and development work in nanotechnology for manufacturing computers at the molecular level. Computers have gone from large and mechanical, like Babbage's Difference Engine, to molecular. Researchers have shown that carbon nanotubes can be strung across electrodes to make minute transistors. Beyond sheer density of data, the nanotube chips have another, perhaps even more important, potential advantage over their electronic rivals: the memory does not disappear when the power goes off. The tubes may be drawn to the electrode by an electrical attraction, but they are held there by van der Waals attraction, a sort of molecular-level suction. In that way, an electromechanical memory chip will have more in common with a computer hard drive or floppy disk than with random access memory. Physicist Paul McEuen and his colleagues at Cornell have fabricated a transistor that passes signals through a single atom.
Calculating Coefficients
Authors: McCullough Robert N.
Published: July 2018

Wilbur and Orville Wright, both engineer brothers, studied results of Germany’s Otto Lilienthal to improve their airplane flight experiments and calculations. The Wright gliders of 1900 and 1901 used wings like Lilienthal’s, and the brothers relied on his calculations for determining coefficient of lift. When the Wrights compared their results with those of Lilienthal, they found only small disagreements. With the coefficients of lift and drag holding up to their scrutiny, the Wrights turned their attention to the only other possible source of error in the equations, the Smeaton coefficient of air pressure. The Wrights built lift balance after discovering a discrepancy between actual and predicted values for lift and drag. The brothers plotted out the relationship among lift, thrust, weight, and drag. The Wrights figured out that the margins are a tribute to their genius. Perhaps all they proved in 1903 was that flight was possible on a cold and windy day in North Carolina.
Surgical Analysis
Authors: Thilmany Jean
Published: July 2018

This article illustrates increasing implementation of engineering technology in the medical industry. Computer images form the basis of models that can guide surgeons through the unique fluid dynamics of each patient. Computer-assisted surgeries, in which doctors get real-time information about their patients as they operate, are becoming more common, but computers still are not usual operating room tools. A medical tool of today could be used in the operating room to capture information about the patient’s condition and feed it to a computer. David Gosman and his team at Imperial College are adapting technology originally developed to simulate airflow through a reciprocating internal combustion engine so that it can be applied to study the human heart. Researchers at the Georgia Institute of Technology in Atlanta are also studying blood flow. They have an eye toward using the information to design better artificial heart valves. Numerical modelling techniques originally developed by the institute to simulate how water flows around hydraulic structures like bridge foundations are finding a second use in helping researchers better understand blood flow patterns through artificial mechanical heart valves.
Lessons of the Blackout
Authors: Fama James
Published: July 2018

The US–Canadian blackout in 2003 demonstrated the need for new reliability measures in the field of the power industry. The Edison Electric Institute, the trade organization for the investor-owned utilities that generate about 70 percent of the electricity consumed in the United States, is taking reliability to Congress. The voluntary organization that oversees bulk electrical transmission on the continent—The North American Electricity Reliability Council, or NERC—began to implement measures to address many of the recommendations later detailed in the report, key among them was reformatting and clarifying its reliability standards. A research insists that in order to balance power generation and demand continuously, production by generators must be scheduled and dispatched to meet constantly changing demands, and adjusted continuously.
Share the Wealth
Authors: Thilmany Jean
Published: July 2018

Honeywell FM&T has found a myriad of ways to pass job know-how from senior to junior engineer. Now executives and managers identify important design areas that can be demonstrated via finite element analysis technology. Then, manufacturing and design engineers as well as analysts can run the demonstrations to learn key parts of each other’s jobs. The simulation advisors are developed under Honeywell’s knowledge capture program, which makes sure that key process information is not lost and is as widely distributed as possible. The company takes a multifaceted approach to what managers at Honeywell refer to as knowledge preservation or knowledge capture. The advisors simulate a manufacturing or engineering process that the new engineer will be called upon to carry out. Newbies can play around with a model. They might change settings on a virtual machine or experiment with how different diameters or materials would affect a part, much as they would when running a part analysis.
A Model Mission
Authors: Wicks Frank
Published: July 2018

This article illustrates details of Maynard Hill, an experimenter, who sent a man in the air on a 600-pound flying machine. He continued to build models throughout high school, during his World War II Navy aviation service, and during his years at Penn State, where he received degrees in metallurgy in 1950 and 1951. Vacuum tube radio made flight control complicated. Hill said he struggled for two years before he achieved a marginally successful flight with a descending glider by means of stepping the rudder position. Hill's plan was to begin the flight under manual radio control, transfer to autopilot for the ocean portion, and then back to radio control for landing by another team waiting in Ireland. The autopilot weighed only a few ounces. It was developed by team member Joe Foster. A challenge was performing a smooth transition from manual to autonomous control and then back to manual for landing. The first attempted flight started successfully on radio control, but failed to stabilize when Joe Foster sent the radio signal to transfer control to autonomous flight. They suspected that the airplane was too far out of trim for the transition. He expertly transferred the airplane to his radio control, cut the engine, and guided it to a dead-stick landing near the monument that marks the 1919 landing spot of John Alcock and Arthur Brown.
Two if by Sea
Authors: Sharke Paul
Published: July 2018

This article discusses that ever since the Methane Pioneer sailed a cargo of liquefied natural gas from the United States to England in 1959, LNG trading in the United States has been a business of fits and starts. A chart plotting the growth of seaborne LNG depicts a flat first decade in the 1960s, 10 years’ rise in the 1970s during the first oil crunch and a flurry of Japanese activity, and then a plateau again in the 1980s on the tail of natural gas price deregulation and a bump up in domestic natural gas production. Bluewater’s concepts for offshore LNG terminals are designed to let a tanker weathervane. Moored at a single point, a weather vaning vessel swings freely to present the lowest area it can to wind and sea. The practice is common with offshore oil handling to keep ship movement from straining the floating hose that carries crude off the ship.
Slides Rule
Authors: Ehrenman Gayle
Published: July 2018

This article reviews a permanent display on the first floor of the Potter Engineering Center that showcases pre-digital analytical marvels at Purdue University in West Lafayette. The display includes about 200 slide rules from Purdue alumni, including astronauts Neil Armstrong, Jerry Ross, Richard Covey, and Roy Bridges. Another Purdue alumnus, Eugene Cernan, the last man to walk on the moon, has promised to send his slide rule, as well. The exhibit is indicative of the attachment—some might say outright affection—that these and other engineers have for an old standby with a long history. The calculator and the computer may have usurped the slide rule’s place in the engineer’s toolbox, but that does not mean the old rule has been forgotten. The oldest slide rule in the exhibit does not date back quite that far, but it does hail from the mid-1800s. In addition to antique specimens, the exhibit includes slide rules made of metal, wood, bamboo, paper, and plastic, as well as two 7-foot-long rules. The oversize slide rules were used in classes to teach students how to use them.
Have Duct Tape, Will Travel
Authors: Winters Jeffrey
Published: July 2018

This article discusses how Amy Smith, a mechanical engineer at the Massachusetts Institute of Technology in Cambridge, has turned simple materials into life-changing tools. One of the first was developing a new type of grain mill that could revolutionize the lives of women in the Third World. A motor-driven mill can accomplish the same task in just a couple of minutes, but motorized mills are difficult to come by and expensive to maintain. Smith realized that coming up with a simpler, cheaper mill would be a boon for many families. Often in underdeveloped areas, this grinding must be done by hand, with women crushing the kernels between a rock or mortar and a flat stone or bowl. Smith’s group has developed a clamp for controlling intravenous fluid that could help nurses care for more patients during an epidemic.
Fahrenheit 3,600
Authors: Langston Lee S.
Published: July 2018

This article illustrates capabilities of gas turbines to be able to work in extremely elevated temperatures. The turbine airfoils in the new F135 jet engine that powers the Joint Strike Fighter (JSF) Lightning II are capable of operating at these extreme temperatures. The F135 gas turbine is the first production jet engine in this new 3,600°F class, designed to withstand these highest, record-breaking turbine inlet temperatures. The JSF engine is just one product in the $3.7 billion military gas turbine market, which includes jet engine production for the world’s fighter aircraft military cargo, transport, refuelling, and special-purpose aircraft. The article also discusses the features of H Class, which is the largest electric power gas turbine that has been interpreted as an abbreviation for humongous. Non-aviation gas turbines consist of electrical power generation, mechanical drive, and marine. The largest segment of that market by far is electrical power generation, in simple cycle, combined cycle, and cogeneration. Forecast International predicts significant growth in coming years in demand for gas turbine electrical power generation, rising from $8.6 billion in 2006 to a projected $13.5 billion in 2008, a 60 percent increase.
The Rebirth of Cool
Authors: Abrams Michael
Published: July 2018

This article discusses design and developments in the refrigeration and compressor fields to deal with Montreal Protocol’s announcement of expiration of R-22 as refrigerant. The Montreal Protocol dictates that by 2010 no new refrigerators or air conditioners will use R-22, a hydrochlorofluorocarbons (HCFC), as a refrigerant. The replacement, known as R-410A, is an HFC (hydrofluorocarbon) rather than an HCFC. Jim Crawford, director of regulatory affairs at The Trane Co., a heating and air conditioning company in Tyler, Texas, said that industry is adopting R-410A primarily in air conditioning. Companies like Trane have used the time allotted by the Montreal Protocol to design, test, and build R-410A equipment for 2010. Compressors have had to be optimized both for the refrigerant and the application. Since the heat characteristics are different between the two refrigerants, heat exchangers must be made larger or smaller. Many new air conditioners, like Trane’s XL16i, already use R-41OA, which contains no chlorine.
Clean Up Duty
Authors: Plenderleith Don
Published: July 2018

This article discusses engineering supervision and engineering efforts in remediation of different sites. Public Works and Government Services Canada, which manages many of the military bases in the Ottawa region, commissioned the environmental and geotechnical firm Golder Associates Ltd. to provide engineering supervision and support for remediation of the site. The remediation of the former military landfill site, conducted in February and March 2006, not only cleaned up a polluted part of the Earth, it also pointed to some of the current best practices being used to protect the environment when working on military properties. Once site remediation began, plans had to be changed quickly, because Golder discovered that parts of the landfill site were dotted with holes that indicated it was being used as a turtle nesting site. Through a literature review, bioscientists determined what kind of aggregate would be most acceptable to the turtles as nesting material. The landfill cap is vegetated with grass and shrubs to consolidate the soil cover layers and prevent their erosion. Given that the site is behind the target area for one of the firing ranges, it does not get much human traffic, but its landscape is in keeping with the surrounding area, and the site poses no more threat to the local ecosystem.
Taking Engineering's Pulse
Authors: Harry Hutchinson
Published: July 2018

This article highlights key points of the Mechanical Engineering Global Summit. According to the participants, much of the future for mechanical engineers will involve integrating systems of all kinds. Throughout the discussions at the meeting, numerous comments concerned the increasingly interdisciplinary nature of engineering practice. Experts believe that vertical farms, for instance, could use hydroponics and other means to take farming indoors, where it could be carried out in multitiered structures. If technology like this could be made practical, it could multiply the area available for agriculture. A multibillion-dollar experiment in sustainable living has been proposed for the United Arab Emirates. The initiative hopes to create a high-tech city that will have zero emissions and be entirely self-sustaining. One of the proposals is to restructure engineering education and to prepare engineers the way lawyers and doctors are trained: a four-year liberal arts education in preparation for the professional degree in postgraduate study.
Design Futures
Authors: Thilmany Jean
Published: July 2018

This article focuses on developing a pen-like device that is expected to soon take the place of the computer mouse. John Hirschtick of SolidWorks expects to see touchscreens and other means of communicating with computers—now familiar in ATM machines, iPhones, and Wii game systems—make their way into more computer interfaces, including those for CAD. Engineers might draw on the screen with a pen-based input or might use a haptic device to feel as though they are grabbing the model to manipulate it. The Internet has spawned companies like Quickparts.com and MFG.com, which have changed the way manufacturers can buy parts. Under the model envisioned by Jakiela, independent mechanical engineers would band together to work on a project through an Internet site. Jakiela is also looking at how to best build a prototype when all design-team members are part of an ad hoc team.
The Many Shades of Green
Authors: Brown Alan S.
Published: July 2018

This review focuses on the fact that there are many ways to be green, and American manufacturers are trying them all. From reducing energy use and recycling water to implementing ISO 14001 sustainability programs and reusing packaging, US factories are embracing a more environmentally sensitive manufacturing ethos as fast as they can. There are many ways to be green. Ratcheting down energy use, for example, automatically reduces a plant’s carbon footprint, because either it burns less natural gas or it buys less electricity from a power plant that burns coal or gas. Companies around the nation have also turned their Six Sigma, lean manufacturing, and other tools on solid waste. If a material does not add value to a product, they eliminate it. Many work with vendors to reduce packaging. The less packaging, the less energy is used in a product. Capital projects are even harder to push through, yet they are necessary for further gains once companies have plucked waste reduction’s low-hanging fruit.
A New Kind of Design
Authors: Thilmany Jean
Published: July 2018

This article highlights three-dimensional printing as a rapid pro to typing process that builds objects by depositing a material such as thermoset resin in layers one on the other. Desktop 3D printers are now relatively inexpensive. Traditionally, printed models have been dipped in an epoxy resin. FigurePrints uses an automated system from xlaForm that allows parts to be infused in bulk in a heating machine. This method cuts processing time and labor costs, but is still time-consuming and allows processing only in batches. Wohlers is also watching Shapeways of Eindhoven in the Netherlands, which has married 3D printing with the crowdsourcing model now being blazed on the Internet. This model asks Internet users to design or create products and then rank the results. At Shapeways, which is actually a business incubator sponsored by Koninklijke Philips Electronics NV, consumers upload their own 3D models, which are then printed and shipped. Users can also purchase models.
Boot Camp for Entrepreneurs
Authors: Brown Alan S.
Published: July 2018

This article discusses the concept of Entrepreneurial Boot Camp that was used by Lucent Company to discover a way to turn small teams of employees into sources of innovative business ideas. The idea behind Entrepreneurial Boot Camp was simple. Small teams of employees would rally around an idea. Anyone could submit an idea or join a team, from researchers to office clerks. First, employees published their ideas on a website. Then everyone interested in joining a team gathered in an auditorium where the idea owners gave five-minute presentations. Afterwards, everyone adjourned to the cafeteria, where idea owners talked with people who wanted to work on a project. Those five people could come from anywhere in Lucent. The Boot Camps continued after Alcatel acquired Lucent in December 2006. More than 80% of the plans accepted by the company’s Innovation Board have been developed into new market opportunities. The most advanced is Touchatag, a wireless service that supports mobile payments, customer loyalty programs, and interactive advertising.
Designing for the Rest of the Global Market
Authors: Winter Amos
Published: July 2018

This article discusses how some engineers are now trying to design products for people living in some of the world’s poorest regions. Engineers have begun to focus more and more on creating and implementing technologies for developing countries. Some of this attention is the result of a number of worthwhile initiatives. The Gates and Clinton Foundations, for example, have given away millions of dollars to spur and support innovative new products to help people at the bottom of the pyramid. Engineers Without Borders has also inspired thousands of students to effect positive change in the world with their technical skills. ASME has added Engineering for Change, an online repository for development technologies and a hub for connecting innovators with stakeholders. The problems of the developing world are expected to gain even greater prominence in the engineering community over the next 20 years. Technical challenges in developing countries will also motivate engineering students, researchers, and professionals, and have a specific attraction to students from demographics typically underrepresented in engineering.
Deus Ex Machina
Authors: Florman Samuel C.
Published: July 2018

In this article, Samuel C. Florman, the chairman of Kreisler Borg Florman General Construction Co. recalls how a sequence of events in 1963 led his young construction firm to $2 million in billings at the World’s Fair. During the summer of 1962, Norman Winston was appointed as the United States Commissioner to the World Fair. He was specifically charged with supervising development and construction of an American pavilion. The construction contract for the pavilion had gone to famous developer Del Webb. However, in late 1963, due to some issues, Del Webb walked out of the project. The job of finishing the federal pavilion was then offered to Florman’s firm. Florman’s firm was to perform miscellaneous finishing items and provide “general oversight.” While the original fee of the firm was a measly $45,000, the amount grew rapidly as the scope of the activities increased. By the time the Fair closed in 1965, Florman’s firm had billed some $2 million on which it earned approximately 20% in gross profit.
The Revolution May Well Be Gasified
Authors: Abrams Michael
Published: July 2018

This article discusses how some people are using wood pellets, corn, grass, and other biomass to power their homes and cars with near zero percent emissions. The process that has inspired these people to do it themselves is not burning, per se, but gasification: the decomposition of biomass into gases that can then be burned cleanly. Moreover, these gases can be sent directly into conventional engines much the way natural gas can. When a carbon-y chunk is heated to a high enough temperature, it begins to break down into methane, carbon monoxide, hydrogen, and other gases, which will readily combust with oxygen to produce a flame. If the oxygen supply is choked off, one can collect the gas to be burned. The synthesized gas, or syngas, can be burned efficiently and with extremely low emissions.
Critical Information
Authors: Bilello Peter A.
Published: July 2018

This article discusses the shift to product lifecycle management (PLM) systems by various mechanical engineering companies. Systems engineers and information-handling experts are joining forces to get a grip on the information explosion, thanks primarily to the timely convergence of systems engineering with digital design and development. PLM supports the extended enterprise. The rationale behind using PLM is to ensure that the ideas and information driving the development of today’s products incorporate best practices and everything learned right up to the product-release date. The rapid increase in electronic controls and software that are being built into key auto components requires that mechanical engineers and electrical engineers work ever more closely together. This highlights the need to integrate the very different approaches to development that the two disciplines use. One of the key functions of PLM is to make sure all the data in those analyses are retained, not just the conclusions.
Dynamic Systems and Control Division
Authors: Auslander David M.
Published: July 2018

This article presents in depth the history activities of the Dynamic Systems and Control Division (DSCD) in the last 20 years. The 10 most cited papers from this 20-year period have been discussed in the article. Of these 10 papers, 4 of them are review or survey articles. The topics vary, showing the scope of DSCD’s activities: system identification, time delay systems, multivehicle control, and elastic manipulator arms. The most cited article is about nanotechnology; other areas represented are machine tool control, mechanical control to minimize vibrations, automotive, and piezoelectric actuators. These papers do stay true to the mechanical engineering roots of the DSCD. Other than the paper on time-delay systems, all of these papers directly reference mechanical systems. Some are application specific and others refer to specific classes of mechanical systems such as flexible manipulators.
Free Form Fluidics
Authors: Love Lonnie J. , Richardson Bradley , Lind Randall , Dehoff Ryan , Peter Bill , Lowe Larry , Blue Craig
Published: July 2018

This article introduces the concept of blending fluid power with mechanical structure through addictive manufacturing. Today, fluid-powered devices are manufactured using conventional fabrication practices. The additive process enables integrated structure, actuation, fluid passages, thermal management, and control within a single fabrication process. Fluid can be routed efficiently through the structure without the need for cross-drilled holes or plugs. Fluid passages can be optimized for heat dissipation and minimized head loss. One of the primary issues regarding parts manufactured using the additive manufacturing process is their mechanical properties. Results show that components made with Ti-6-4 powders have a minimum yield stress and ultimate strength that exceeds Grade 5 specifications. The Arcan system uses a powder bed that has an elevated temperature. Therefore, the part exhibits very little residual stress during the manufacturing process. This leads to improved mechanical strength but induces challenges in powder removal. The specific advantages are reduced weight, potential for lower cost, and reduced part counts.
Controlling Wind Energy for Utility Grid Reliability
Authors: Aho Jacob P. , Buckspan Andrew D. , Dunne Fiona M. , Pao Lucy Y.
Published: July 2018

This article provides an overview of utility grid operation by introducing the fundamental behavior of the electrical system, explaining the importance of maintaining grid reliability through balancing generation and load, and describing the methods of providing ancillary services using conventional utilities. This article also introduces the basic structural components of wind turbines, explains the traditional control systems for capturing maximum power, and highlights control methods developed in industry and academia to provide active power ancillary services with wind energy. As the penetration of wind energy continues to grow, the participation of wind turbines and wind farms in grid frequency stability is becoming more important. The future of wind energy development and deployment depends on many factors, such as policy decisions, economic markets, and technology improvements. Improvements through research and development in areas such as forecasting, turbine manufacturing processes, blade aerodynamics, power electronics, and active power control systems will continue to be a key driver for wind energy technology.
Numerical Study on Fuel Preheating at Cold Start Phase in an Ethanol Flex Fuel Engine
Authors: Wang Ying , Liu Zhensheng
Published: July 2018

The low vapor pressure of ethanol and the high latent heat of vaporization at low temperatures cause the difficulties of cold start in a flex fuel vehicle when it is fueled with pure ethanol. Preheating fuel is one of the effective methods to solve the above cold start problem. Thus, it is crucial to obtain the fuel temperature distribution in the heating system for fuel preheating process. For this purpose, the numerical analysis is adopted here to simulate the fuel preheating process at a cold start phase and explore the change of the fuel temperature field under different influence factors. The results indicate that the starting temperature has obvious impact on the temperature field distribution in the heating chamber and preheating time but has little effect on the volume of cold fuel in the connecting line at the end of heating. When the starting temperature is −5 °C, the preheating time is 8.3 s. When the starting temperature increases up to 15 °C, the preheating time will decrease as 4.9 s. Furthermore, the lower the starting temperature is, the higher the overall temperature of the heating chamber is. The installing angle of injectors has some influence on the temperature field distribution, and the cold fuel ratio reduces slightly when the angle increases from 30 deg to 60 deg. The calculation results indicate that the temperature of fuel at the injector inlet is above 20 °C, and the fuel injected during the first three cycles of the engine operation is hot fuel.
Combustion Performance and Unburned Hydrocarbon Emissions of a Natural Gas–Diesel Dual Fuel Engine at a Low Load Condition
Authors: Guo Hongsheng , Liko Brian , Luque Luis , Littlejohns Jennifer
Published: July 2018

The combustion of natural gas reduces fuel cost and generates less emissions of carbon dioxide and particulate matter (PM) than diesel and gasoline. Replacing diesel by natural gas in internal combustion engines is of great interest for transportation and stationary power generation. Dual fuel combustion is an efficient way to burn natural gas in internal combustion engines. In natural gas–diesel dual fuel engines, unburned hydrocarbon emissions increase with increasing natural gas fraction. Many studies have been conducted to improve the performance of natural gas–diesel dual fuel engines and reported the performance of combustion and emissions of regulated pollutants and total unburned hydrocarbon at various engine operating strategies. However, little has been reported on the emissions of different unburned hydrocarbon components. In this paper, an experimental investigation was conducted to investigate the combustion performance and emissions of various unburned hydrocarbon components, including methane, ethane, ethylene, acetylene, propylene, formaldehyde, acetaldehyde, and benzaldehyde, at a low engine load condition. The operating conditions, such as engine speed, load, intake temperature, and pressure, were well controlled during the experiment. The combustion and emissions performance of pure diesel and natural gas–diesel dual fuel combustion were compared. The effect of diesel injection timing was analyzed. The results show that appropriately advancing diesel injection timing to form a homogeneous charge compression ignition (HCCI)-like combustion is beneficial to natural gas–diesel dual fuel combustion at low load conditions. The emissions of different unburned hydrocarbon components changed in dual fuel combustion, with emissions of some unburned hydrocarbon components being primarily due to the combustion of natural gas, while those of others being more related to diesel combustion.
Multiple-Relaxation-Time Lattice Boltzmann Simulation of Flow and Heat Transfer in Porous Volumetric Solar Receivers
Authors: Zhao Wandong , Zhang Ying , Xu Ben , Li Peisheng , Wang Zhaotai , Jiang Shuisheng
Published: July 2018

The flow and heat transfer (FHT) in porous volumetric solar receiver was investigated through a double-distributed thermally coupled multiple-relaxation-time (MRT) lattice Boltzmann model (LBM) in this study. The MRT-LBM model was first verified by simulating the FHT in Sierpinski carpet fractal porous media and compared with the results from computational fluid dynamics (CFD). Three typical porous structures in volumetric solar receivers were developed and constructed, and then the FHT in these three porous structures were investigated using the MRT-LBM model. The effects of pore structure, Reynolds (Re) number based on air velocity at inlet, the porosity, and the thermal diffusivity of solid matrix were discussed. It was found that type-III pore structure among the three typical porous structures has the best heat transfer performance because of its lowest maximum temperature of solid particles at the inlet and the highest average temperature of air at the outlet, under the same porosity and heat flux density. Furthermore, increasing the thermal diffusivity of solid particles will lead to higher averaged air temperature at the outlet. It is hoped that the simulation results will be beneficial to the solar thermal community when designing the solar receivers in concentrated solar power (CSP) applications.
Beyond Brayton Cycle: It is Time to Change the Paradigm
Authors: Can Gülen S.
Published: July 2018

A detailed look at the gas turbine (GT) technology over the last three decades clearly shows that an asymptotic limit is reached in thermal efficiency in combined cycle (CC) configuration. There is little reason to expect a technology leap anytime soon to change this appreciably as long as the industry sticks to the classic Brayton cycle configuration and the brute force approach of ever higher turbine inlet temperatures (TITs). The changing landscape of electric power generation, especially integration of fossil fuel fired technologies with renewable generation and wide variation in natural gas prices, suggests that it is time to look at the direction of future development efforts differently. This paper looks at the need of a paradigm shift in GT CC technology using thermodynamic and economic arguments.
Kinematics of an Articulated Connecting Rod and Its Effect on Simulated Compression Pressures and Port Timings
Authors: Fieseler Kelsey , Jacobs Timothy J. , Patterson Mark
Published: July 2018

This study discusses the motion of the articulated connecting rod of an integral-engine compressor and the effect of the kinematics on in-cylinder pressure and port timings. A piston position modeling technique based on kinematics and engine geometry is proposed in order to improve the accuracy of simulated in-cylinder compression pressures. Many integral-engine compressors operate with an articulated connecting rod. For this type of engine-driven compressor, two power pistons share a crank throw with the compressor. The hinge pins that attach the power piston connecting rods to the crank are offset, causing the piston locations for each cylinder to be out of phase with each other. This causes top dead center (TDC) to occur at different crank angles, alters the geometric compression ratio, and also changes the port timings for each cylinder. In this study, the equations of motion for the pistons of the four possible compressor/piston configurations of a Cooper-Bessemer GMW are developed. With the piston profiles, the intake and exhaust port timings were determined and compared to those of a slider-crank mechanism. The piston profile was then inputted into GT-POWER, an engine modeling software developed by Gamma Technologies, in order to obtain an accurate simulation match to the experimental in-cylinder pressure data collected from a Cooper-Bessemer GMWH-10C. Assuming the piston motion of an engine with an articulated connecting rod is similar to a slider-crank mechanism can create a difference in port timings. The hinge pin offset creates asymmetrical motion about 180°aTDC, causing the port timings to also be asymmetrical about this location. The largest differences are shown in the intake port opening of about 10 deg and a difference in exhaust port opening of about 7 deg when comparing the motion of the correct configuration to the motion of a slider-crank mechanism. It is shown that properly calculating the piston motion profiles according to the crank articulation and engine geometry provides a good method of simulating in-cylinder pressure data during the compression stroke.
Prediction of CO and NOx Pollutants in a Stratified Bluff Body Burner
Authors: Gruhlke Pascal , Proch Fabian , Kempf Andreas M. , Dederichs Stefan , Beck Christian , Mahiques Enric Illana
Published: July 2018

The major exhaust gas pollutants from heavy duty gas turbine engines are CO and NOx. The difficulty of predicting the concentration of these combustion products originates from their wide range of chemical time scales. In this paper, a combustion model that includes the prediction of the carbon monoxide and nitric oxide emissions is tested. Large eddy simulations (LES) are performed using a compressible code (OpenFOAM). A modified flamelet generated manifolds (FGM) approach is applied with an artificially thickened flame approach (ATF) to resolve the flame on the numerical grid, with a flame sensor to ensure that the flame is only thickened in the flame region. For the prediction of the CO and NOx emissions, pollutant species transport equations and a second, CO based, progress variable are introduced for the flame burnout zone to account for slow chemistry effects. For the validation of the models, the Cambridge burner of Sweeney et al. (2012, “The Structure of Turbulent Stratified and Premixed Methane/Air Flames—I: Non-Swirling Flows,” Combust. Flame, 159, pp. 2896–2911; 2012, “The Structure of Turbulent Stratified and Premixed Methane/Air Flames—II: Swirling Flows,” Combust. Flame, 159, pp. 2912–2929.) is employed, as both carbon monoxide and nitric oxide [Apeloig et al. (2016, “PLIF Measurements of Nitric Oxide and Hydroxyl Radicals Distributions in Swirl Stratified Premixed Flames,” 18th International Symposium on the Application of Laser and Imaging Techniques to Fluid Mechanics, Lisbon, Portugal, July 4–7.)] data are available.
Wet Steam Nonequilibrium Condensation Flow-Induced Vibrations of a Nuclear Turbine Blade
Authors: Guo Bing , Tang Weixiao
Published: July 2018

Condensing flow induced vibration (CFIV) of the rotor blade is a tough problem for designers of nuclear turbines because nonequilibrium condensing flow excitation (NECFE) is hard to be directly modeled. Generally, in design, NECFE is assumed as equilibrium condensing flow excitation (ECFE), of which the pressure fluctuations caused by phase temperature difference (PTD) between gaseous and liquid are ignored. In this paper, a novel method to calculate the equivalent load of NECFE based on the principle of virtual work was proposed. This method could consider the effects of PTD-induced pressure fluctuations by simulating nonequilibrium condensation with ANSYS cfx, and improve computational efficiency. Once the equivalent NECFE load is determined, CFIV of the rotor blade, which was modeled as a pretwisted asymmetric cantilever beam, can then be predicted by the finite element method (FEM). Additionally, to estimate the effects of PTD-induced pressure fluctuations, comparisons between NECFE and ECFE as well as their induced vibrations were presented. Results show that PTD in nucleation area could change the position and type of shock waves, restructure the pressure distribution, as well as enhance the pressure fluctuations. Compared with ECFE, the frequency ingredients and amplitude of the equivalent NECFE load and its induced vibrations are increased. Specifically, the amplitude of the equivalent NECFE load is increased by 9.38%, 15.34%, and 7.43% in the tangential component, axial component, and torsion moment. The blade vibration responses induced by NECFE are increased by 11.66% and 19.94% in tangential and axial.
A Study on Slip Characteristics Using Hybrid Particle-Continuum Method
Authors: Yang Jiandong , Wan Zhenhua , Wang Liang , Sun Dejun
Published: July 2018

An effective boundary potential has been proposed to solve nonperiodic boundary condition (NPBC) of hybrid method. The optimized hybrid method is applied to investigate the influences of the channel height and solid–liquid interaction parameters on slip characteristics of Couette flows in micro/nanochannels. By changing the channel height, we find that the relative slip lengths show the obvious negative correlation with the channel height and fewer density oscillations are generated near the solid wall in the larger channel height. Moreover, we continue to investigate the solid–liquid interaction parameters, including the solid–liquid energy scales ratio (C1) and solid–liquid length scales ratio (C2). The results show that the solid–liquid surface changes from hydrophobic to hydrophilic with the increase of C1, the arrangement of liquid particles adjacent to the solid particles is more disorganized over the hydrophobic solid–liquid surface compared with the hydrophilic surface, and the probability of the liquid particles that appear near the solid particles becomes smaller. Meanwhile, the relative slip lengths are minimum when the liquid and solid particles have the same diameter. Furthermore, the relative slip lengths follow a linear relationship with the shear rate when the solid–liquid interaction parameters change. The plenty computational time has been saved by the present hybrid method compared with the full molecular dynamics simulation (FMD) in this paper.
Velocity and NO-Lifetime Measurements in an Unseeded Hypersonic Air Flow
Authors: Matos Pedro A. de S. , Barreta Luiz G. , Martins Cristiane A.
Published: July 2018

A laser-induced fluorescence (LIF)-based nitric-oxide flow-tagging technique was applied to measure both velocity and NO lifetime in a hypersonic shock tunnel from two experimental test runs. The results were supported by an analytical profile proposed in this paper that provides a way to correct velocity measurements under unknown systematic error sources. This procedure provided velocities with discrepancies lower than 3% for a total of five measurements, and lower than 2% when compared with that obtained from a linear fit. Additionally, the comparison between the proposed and experimental profiles allowed us to obtain the fluorescence NO lifetime from only one image.