USCG Patrol Craft Hydrodynamic Fuel Efficiency Improvements

2015 ◽  
Author(s):  
Brant R. Savander ◽  
Malcolm E. Willis ◽  
Karl A. Stambaugh ◽  
Kelley A. Cox
Keyword(s):  
Fuel Efficiency ◽  
Cost Savings ◽  
Fast Response ◽  
Operating Life ◽  
Alignment Procedure ◽  
Similar Work ◽  
Brake Power ◽  
Rail System ◽  
Final System ◽  
Rudder Cavitation

A computational analysis program, conducted at full scale, has been completed on the USCG Fast Response Cutter (FRC) to evaluate how appendage and propeller redesign affects calm water powering performance and erosive cavitation onset. Aft working forward, the geometric variations considered included: addition of a stern flap, wake adapted rudder redesign, propeller design refinement, wake adapted skeg redesign, and redesign of the spray rail system. The first activity was to use a wake alignment procedure to redesign the current rudder in an effort to improve the rudder drag characteristics and minimize or eliminate rudder cavitation. The wake aligned redesign eliminated rudder cavitation over the entire speed range, and decreased total drag by 6% at flank speed. Replacement of only the current rudders with the wake aligned redesign is predicted to increase flank speed from 28.9 knots to 29.4 knots. The stern flap and spray rail efforts followed the historical guidance of similar work performed on the USCG Island Class patrol boats, as documented in Cusanelli and Barry (2002). Following the geometric guidance of the Island Class stern flaps the final recommended stern flap for the FRC results in a brake power demand reduction of 15%. The Island Class achieved a 12% reduction in required brake power at similar speeds. The combination of the new stern flap, wake adapted rudders, current propeller, current skegs, and new spray rail yielded an increase in flank speed from 28.9 to 31.4 knots. Skeg redesign resulted in a 30% decrease in the magnitude of the radiated pressure pulse amplitudes experienced in the propeller tunnel above the propeller. The redesign of the skeg did not affect the propeller behind efficiency. Modification of the current propeller geometry was the final redesign task. The final system, which included the new stern flap, wake aligned rudders, redesigned propeller, wake aligned skegs, and new spray rail system decreased power by 18.6% at the prior 28.9 knot flank speed of FRC. The new flank speed, with the final system, has increased to 32.9 knots in the full load, end of service life condition. The combined effect of all redesign activities reveals an annual fuel consumption savings of 24,000 gallons per vessel per year, which corresponds to a 13.6% savings when compared to the original as-built system. Assuming a fuel cost of $4 per gallon, the annual cost savings per vessel per year equals $96,000. This savings extrapolated over a 58 ship fleet equates to $5.5 million in savings per year for the class. This saving per year yields a savings of $110 million for the 20-year operating life of the 58-ship class.

Nanoscale Studies of the Role of ZDDPs in the Wear Protection in the Automobile Engine

2007 ◽  
Author(s):  
P. R. Norton ◽  
Gavin Pereira ◽  
Yue-Rong Li ◽  
Andreas Lachenwitzer ◽  
Masoud Kasrai ◽  
...  
Keyword(s):  
Automobile Industry ◽  
Fuel Efficiency ◽  
Cost Savings ◽  
Engine Oil ◽  
Protective Film ◽  
Oil Additives ◽  
Wear Protection ◽  
Alternative Materials ◽  
Dialkyl Dithiophosphates

The improvement of fuel consumption is an important driving force for research and development in the automobile industry in order to minimize greenhouse gas emissions as well as improving fuel economy. Aluminum alloys are a class of alternative materials that are being used to replace cast iron in motor components due to the concomitant weight savings which result in improved fuel efficiency, and cost savings. Our research focuses on these alternative Al-based alloys as well as traditional steel interfaces, and the protective films that form on the surfaces. Currently the zinc dialkyl-dithiophosphates (ZDDPs) have been used as engine oil additives for over 60 years. They are important chemically-active additives, known for their antioxidant and antiwear characteristics. ZDDPs are known to form a protective film (tribofilms) at rubbed surfaces, typically on iron containing metals surfaces commonly used in the automotive industry; however ZDDPs and the products formed are not well suited for the environment as they can readily poison the catalytic converters and their efficacy on Al-Si alloys is not well established.

Dross Processing Technology

2009 ◽  
Vol 630 ◽  
pp. 53-60 ◽  
Author(s):  
Alan Peel ◽  
James Herbert ◽  
David Roth ◽  
Martin J. Collins
Keyword(s):  
Fuel Efficiency ◽  
Cost Savings ◽  
Environmental Benefits ◽  
Aluminium Content ◽  
Cast House ◽  
Metal Quality ◽  
Refractory Life ◽  
A Company ◽  
Insight Into

While it is generally acknowledged that dross generation should be kept to a minimum, too often the importance of maximizing the aluminium content of the dross is overlooked. Some mistakenly believe that a low metal content is a good thing and that the aluminium is being kept in the furnace. In reality, this metal is most likely being lost due to insufficient cooling and thermiting. Much can be gleaned from looking at the dross that is generated in a casthouse; in fact, the quality of dross can provide a good indication of the overall efficiency of the operation. Even with the very low aluminium prices of today of about US$1400 per tonne, a recovery improvement of just 3% for a facility producing 500t of dross per month can provide savings in excess of $250.000 per year. Effective dross management also results in better metal quality, improved fuel efficiency, prolonged refractory life and improved profitability in the entire facility. Over the years, as facilities have focused on better dross cooling and handling techniques, dross recoveries have improved. Today, dross recoveries should be in the range of 60 – 70%. These numbers will raise debate but 30 years of experience give us deep insight into these results. The paper looks at the different techniques of handling the dross that is produced within the melting/casting operation with the objective of maximizing aluminium recovery. This paper will consider both the initial dross handling within the cast house but then also how secondary processors should be evaluated to maximize the value of the dross being processed. A company can lose as much dross recovery opportunity here as in their own facility. . In summary, by careful attention to the equipment and process techniques around the furnace and the follow-on dross management, significant cost savings and environmental benefits can be realized by cast house operations.

scholarly journals A Parametric Study of Actuator Requirements for Active Turbine Tip Clearance Control of a Modern High Bypass Turbofan Engine

2017 ◽  
Author(s):  
Jonathan L. Kratz ◽  
Jeffryes W. Chapman ◽  
Ten-Huei Guo
Keyword(s):  
Parametric Study ◽  
Fuel Efficiency ◽  
Turbine Blades ◽  
Aircraft Engine ◽  
Fast Response ◽  
Tip Clearance ◽  
Inlet Temperature ◽  
Actuation System ◽  
Efficiency Increase ◽  
Clearance Control

The efficiency of aircraft gas turbine engines is sensitive to the distance between the tips of its turbine blades and its shroud, which serves as its containment structure. Maintaining tighter clearance between these components has been shown to increase turbine efficiency, increase fuel efficiency, and reduce the turbine inlet temperature, and this correlates to a longer time-on-wing for the engine. Therefore, there is a desire to maintain a tight clearance in the turbine, which requires fast response active clearance control. Fast response active tip clearance control will require an actuator to modify the physical or effective tip clearance in the turbine. This paper evaluates the requirements of a generic active turbine tip clearance actuator for a modern commercial aircraft engine using the Commercial Modular Aero-Propulsion System Simulation 40k (C-MAPSS40k) software that has previously been integrated with a dynamic tip clearance model. A parametric study was performed in an attempt to evaluate requirements for control actuators in terms of bandwidth, rate limits, saturation limits, and deadband. Constraints on the weight of the actuation system and some considerations as to the force which the actuator must be capable of exerting and maintaining are also investigated. From the results, the relevant range of the evaluated actuator parameters can be extracted. Some additional discussion is provided on the challenges posed by the tip clearance control problem and the implications for future small core aircraft engines.

Furnace Operations to Reduce Dross Generation

2009 ◽  
Vol 630 ◽  
pp. 45-52 ◽  
Author(s):  
Alan Peel ◽  
James Herbert ◽  
David Roth ◽  
Martin J. Collins
Keyword(s):  
Fuel Efficiency ◽  
Cost Savings ◽  
Environmental Benefits ◽  
Aluminium Content ◽  
Cast House ◽  
Metal Quality ◽  
Significant Cost ◽  
Surface Circulation ◽  
Refractory Life

While it is generally acknowledged that dross generation should be kept to a minimum, too often, the importance of maximising the aluminium content of the dross is overlooked. Some mistakenly believe that a low metal content is a good thing and that the aluminium is being kept in the furnace. In reality, this metal is most likely being lost due to insufficient cooling and thermiting. Much can be gleaned from looking at the dross that is generated in a casthouse; in fact, the quality of dross can provide a good indication of the overall efficiency of the operation. Even with the very low aluminium prices of today, of circa. US$1400 per tonne, a reduction in dross generation within the furnace can provide huge savings per year. Effective dross management also results in better metal quality, improved fuel efficiency, prolonged refractory life and improved yield in the entire facility. This paper will look at how dross is generated within the furnace in the first place, followed by ways to minimize the dross generation within the furnace using continuous and sub-surface circulation which can also provide significant energy and CO2 reductions. A separate paper will discuss dross processing options and possibilities. In summary, by careful attention to the equipment and process techniques around the furnace and the follow-on dross management significant cost savings and environmental benefits can be realized by cast house operations.

scholarly journals Full-Scale Implementation of RES and Storage in an Island Energy System

Inventions ◽  
2020 ◽  
Vol 5 (4) ◽  
pp. 52
Author(s):  
Konstantinos Fiorentzis ◽  
Yiannis Katsigiannis ◽  
Emmanuel Karapidakis
Keyword(s):  
Energy Storage ◽  
Power System ◽  
Renewable Energy Sources ◽  
Storage System ◽  
Cost Savings ◽  
Energy System ◽  
Energy Storage System ◽  
Fast Response ◽  
Full Scale ◽  
Battery Energy

The field of energy, specifically renewable energy sources (RES), is considered vital for a sustainable society, a fact that is clearly defined by the European Green Deal. It will convert the old, conventional economy into a new, sustainable economy that is environmentally sound, economically viable, and socially responsible. Therefore, there is a need for quick actions by everyone who wants to move toward energy-efficient development and new environmentally friendly behavior. This can be achieved by setting specific guidelines of how to proceed, where to start, and what knowledge is needed to implement such plans and initiatives. This paper seeks to contribute to this very important issue by appraising the ability of full-scale implementation of RES combined with energy storage in an island power system. The Greek island power system of Astypalaia is used as a case study where a battery energy storage system (BESS), along with wind turbines (WTs), is examined to be installed as part of a hybrid power plant (HPP). The simulation’s results showed that the utilization of HPP can significantly increase RES penetration in parallel with remarkable fuel cost savings. Finally, the fast response of BESS can enhance the stability of the system in the case of disturbances.

scholarly journals Gas Turbine Exhaust Systems: Design Considerations

1987 ◽  
Author(s):  
Roy A. Morris
Keyword(s):  
Gas Turbine ◽  
Systems Design ◽  
Exhaust System ◽  
Cost Savings ◽  
Operating Life ◽  
Power Turbine ◽  
Additional Input ◽  
Gas Turbine Exhaust ◽  
Turbine Exhaust

The users of Gas Turbine powered equipment are very careful to ensure that they achieve their objectives in terms of power output and overall efficiency, but other important aspects of the system may be underspecified, and cause the user serviceability and maintenance problems during the systems planned operating life. One important area, crucial to reliable operation of the Gas Turbine, is the power turbine exhaust system. If particular care is not taken on the part of the user in specifying this component, he is likely to be provided with the minimum standard of equipment from the supplier. This paper highlights some of the areas that should be considered during the preparation of specifications, and in the evaluation of proposals. Specific problems of exhaust design will be addressed to assist the user to identify and question possible problem areas. The paper concludes that for minimal additional input during the initial stages of a project, long term cost savings could be made and that the overall system would be more reliable.

Hydrocarbon Impacts on Diesel HCCI Engine Cycles

2009 ◽  
Author(s):  
Ming Zheng ◽  
Usman Asad ◽  
Xiaoye Han ◽  
Meiping Wang ◽  
Graham T. Reader
Keyword(s):  
Empirical Studies ◽  
Fuel Efficiency ◽  
Nox Reduction ◽  
Fast Response ◽  
Nox Emission ◽  
Low Temperature Combustion ◽  
Engine Exhaust ◽  
Temperature Combustion ◽  
Surrogate Fuel ◽  
The Impact

Thermal efficiency and NOx emission comparisons are made between the homogeneous charge compression ignition (HCCI) and the conventional diesel cycles on a number of common-rail diesel engine platforms of high compression ratios with conventional diesel fuel and dimethyl ether as a surrogate fuel. The empirical studies have been conducted under independently controlled exhaust gas recirculation (EGR), intake boost, and exhaust backpressure. The energy relevance of the combustible substances such as carbon monoxide and hydrocarbon species in the engine exhaust has been evaluated quantitatively. However, the impact of the hydrocarbons produced during the HCCI cycles on the attainment of ultra low levels of NOx is less understood and it is unclear if the hydrocarbon species are a precursor to the ultra low NOx and also contribute in part to the NOx reduction. Therefore, the chemical impact of the hydrocarbon species on the NOx emission under low temperature combustion cycles has been examined with crank-angle resolved in-cylinder sampling techniques and fast-response emission analyzers. This paper intends to identify the major impacts of the hydrocarbons on the fuel efficiency and emissions of diesel HCCI cycles.

scholarly journals Telecommunication Systems for Small Satellites Operating at High Frequencies: A Review

Information ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 258
Author(s):  
Alessandra Babuscia
Keyword(s):  
New Technologies ◽  
Cost Savings ◽  
Low Earth Orbit ◽  
Lessons Learned ◽  
Small Satellite ◽  
High Frequencies ◽  
Small Satellites ◽  
Telecommunication Systems ◽  
X Band ◽  
Final System

Small Satellites and in particular CubeSats are becoming extremely popular platforms with which to perform space research. They allow for rapid prototyping with considerable cost savings with respect to traditional missions. However, as small satellite missions become more ambitious in terms of destinations to reach (from Low Earth Orbit to interplanetary) and in terms of the amount of data to transmit, new technologies need to be developed to provide adequate telecommunication support. This paper aims to review the telecommunication systems that have been developed at the Jet Propulsion Laboratory for some of the most recent CubeSat missions operating at different frequency bands: ASTERIA (S-Band), MarCO (X-Band and UHF) and ISARA (Ka-Band and UHF). For each of these missions: the telecommunication challenges and requirements are listed; the final system design is presented; the characteristics of the different hardware components are shown; and the lessons learned through operations are discussed.

A lifecycle cost model considering both component and system burn-in for operationally unrepairable systems

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Kah How Teo ◽  
Kang Tai ◽  
Vincenzo Schena ◽  
Luca Simonini
Keyword(s):  
System Reliability ◽  
Cost Model ◽  
Cost Savings ◽  
Large System ◽  
Content Type ◽  
Small Satellites ◽  
Procedure Cost ◽  
Warranty Costs ◽  
Final System ◽  
Minimum System

PurposeThis study presents a lifecycle cost model considering multi-level burn-in for operationally unrepairable systems including assembly and warranty costs. A numerical method to obtain system reliability under component replacement during burn-in is also presented with derived error bounds.Design/methodology/approachThe final system reliability after component and system burn-in is obtained and warranty costs are computed. On failure during operation, the system is replaced with another that undergoes an identical burn-in procedure. Cost behaviours for a small and large system are shown in a numerical example.FindingsThere are more cost savings when system burn-in is conducted for a large system whereas a strategy focusing on component burn-in only can also result in cost savings for small systems. In addition, a minimum system burn-in duration is required before cost savings are achieved for these operationally unrepairable systems.Originality/valueThe operationally unrepairable system is a niche class of systems which small satellites fall under and no such study has been conducted before. The authors present a different approach towards the testing of small satellites for a constellation mission.

scholarly journals Effect of Heavy-Truck Platooning Fuel-Efficiency Gains on Overall Fuel Efficiency

2019 ◽  
Vol 2673 (5) ◽  
pp. 188-196 ◽  
Author(s):  
Oscar Franzese ◽  
Mary Beth Lascurain ◽  
Luke W. Loy
Keyword(s):  
National Laboratory ◽  
Fuel Efficiency ◽  
Cost Savings ◽  
Department Of Energy ◽  
Efficiency Gain ◽  
Fuel Cost ◽  
Efficiency Gains ◽  
Real World Data ◽  
Oak Ridge ◽  
Heavy Truck

Many studies addressing the fuel-efficiency gains derived from heavy-truck platooning operations have shown that it is possible to achieve increases in fuel efficiency of 10% or more. These studies focus only on the gains realized while traveling under platooning conditions (i.e., highway speeds sustained for sizable intervals of time). However, heavy-truck long-haul operations involve many other travel conditions that fall outside platooning-travel conditions. This paper studies the effect of platooning fuel-efficiency gains on the fuel efficiency of the overall operation. The authors used real-world data collected by the Oak Ridge National Laboratory for a U.S. Department of Energy study to determine the percentage of distance traveled that is “platoonable.” With this and the fuel consumption information collected in the study, the fuel-efficiency gain for the entire operation was computed, as well as annual fuel cost savings.

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