High Performance Spindle Systems for Heavy Duty Milling of Difficult-To-Cut Aerospace Materials

2012 ◽  
Vol 6 (1) ◽  
pp. 43-56
Author(s):  
Masakazu Soshi ◽  
Shinji Ishii ◽  
Peter Fonda ◽  
Kazuo Yamazaki
Keyword(s):  
High Performance ◽  
Heavy Duty ◽  
Aerospace Materials

Probabilistic Fracture Mechanics for Heavy Duty Gas Turbine Rotor Forgings

2017 ◽  
Author(s):  
Kai Kadau ◽  
Phillip W. Gravett ◽  
Christian Amann
Keyword(s):  
Fracture Mechanics ◽  
High Performance ◽  
Computing Methodology ◽  
Direct Simulation Monte Carlo ◽  
Turbine Rotor ◽  
Heavy Duty ◽  
Element Analysis ◽  
Probabilistic Fracture Mechanics ◽  
Risk Of Failure ◽  
Heavy Duty Gas Turbine

We developed and successfully applied a direct simulation Monte-Carlo scheme to quantify the risk of fracture for heavy duty rotors commonly used in the energy sector. The developed Probabilistic Fracture Mechanics high-performance computing methodology and code ProbFM routinely assesses relevant modes of operation for a component by performing billions of individual fracture mechanics simulations. The methodology can be used for new design and life-optimization of components, as well as for the risk of failure quantification of in service rotors and their re-qualifications in conjunction with non-destructive examination techniques, such as ultrasonic testing. The developed probabilistic scheme integrates material data, ultra-sonic testing information, duty-cycle data, and finite element analysis in order to determine the risk of failure. The methodology provides an integrative and robust measure of the fitness for service and allows for a save and reliable operation management of heavy duty rotating equipment.

scholarly journals Analysis and Design of a High-Performance Traction Motor for Heavy-Duty Vehicles

Energies ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 3150
Author(s):  
Dong-Kyu Lee ◽  
Jong-Suk Ro
Keyword(s):  
Design Process ◽  
High Performance ◽  
Permanent Magnet Synchronous Motor ◽  
Harmonic Distortion ◽  
Heavy Vehicles ◽  
Heavy Duty ◽  
Traction Motor ◽  
Analysis And Design ◽  
Power Characteristics ◽  
Heavy Duty Vehicles

Due to environmental issues and depletion of resources, global attentiveness in electric vehicles (EVs) is growing. In particular, research on high specification motors for driving large EVs has attracted a lot of attention. In this study, an analysis and design process for a motor that can be universally applied in heavy vehicles to reduce environmental pollution was introduced. Motors for driving heavy vehicles require high specifications. Thus, an interior permanent magnet synchronous motor (IPMSM) with a delta-shaped magnet array was used to improve the torque and power characteristics. A step skew rotor structure was also used to dampen vibration and noise by minimizing the high-order harmonics in the cogging torque. The proposed analysis and design approach also reduces the total harmonic distortion (THD) of the back electromotive force (EMF). The effectiveness of the proposed analysis and design process and the usefulness of the resulting high-performance traction motor for heavy-duty vehicles were verified via the finite element method (FEM) and by experiment.

High-Performance Lead-Free Electroplated Composite Bearing Overlay for Heavy Duty Applications

2013 ◽  
Author(s):  
Roger Gorges ◽  
Ronald Brock
Keyword(s):  
Fatigue Resistance ◽  
Boundary Lubrication ◽  
Metal Matrix ◽  
High Performance ◽  
New Technologies ◽  
Material Selection ◽  
Lead Free ◽  
Small Scale ◽  
Heavy Duty ◽  
Hard Particles

Material selection for engine internal components, e.g. bearings, is becoming increasingly more complex and demanding as the operating environments become more aggressive with the introduction of new technologies for the reduction of CO2 emissions. Historically, engine bearings contained lead, which has excellent fundamental bearing properties such as compatibility (run satisfactorily under conditions of marginal lubrication), conformability (deform and accept small scale geometrical inaccuracies of the crankshaft), and embeddablity (tolerance to dirt and other foreign materials) whilst being readily alloyed to achieve good wear and fatigue resistance. However, facing new challenges, many Original Equipment Manufacturers have started development programs to replace lead-containing with lead-free engine components in order to comply with new end-of-life vehicle directives or anticipated future directives. For more than fifteen years, MAHLE has been successfully supplying the light, medium and heavy duty market, with premium electroplated leaded composite bearings, which are designed to improve wear resistance. Some of this market now demands a switch to lead-free materials, while maintaining or exceeding its aforementioned requirements on bearing material properties. Composites of hard particles in a softer metal matrix are in this context ideally suited bearing materials as they can be tailored to obtain the optimal mix between soft and hard properties for the individual application. Typical hard particles that are commonly used comprise of metal oxides, nitrides or carbides. In addition to higher load carrying capabilities and longer service life, new engine technology trends demand that bearings also must operate under mixed or boundary lubrication conditions without having any adverse effect on the performance and integrity of the engine system. Boundary lubrication is commonly observed upon starting the engine before the elastohydrodynamic oil film is fully established. In this state, load is carried by surface asperities rather than by the lubricant. So far, the incorporation and even distribution of the hard particles into an electroplated lead-free matrix was not achievable using conventional direct current electroplating techniques. MAHLE, therefore, has developed a patented pulse plating technique in order to incorporate hard particles into the overlay metal matrix. The refined and modified crystal structure of the resulting lead-free overlay, with incorporated hard particles, yields a premium electroplated bearing with superior wear and fatigue resistance. Corresponding rig and engine test results have been completed to support the material development.

Potential of miller timing with synthetic diesel fuels on a single cylinder heavy-duty engine

2021 ◽  
pp. 146808742110436
Author(s):  
Simon Pöllmann ◽  
Martin Härtl ◽  
Georg Wachtmeister
Keyword(s):  
Nitrogen Oxides ◽  
Diesel Fuel ◽  
High Performance ◽  
Internal Combustion Engines ◽  
Soot Formation ◽  
Cetane Number ◽  
Boost Pressure ◽  
Heavy Duty ◽  
Simultaneous Application ◽  
Single Cylinder

Upcoming emission limits such as Euro VII will make it necessary to further reduce the NOx emission level of internal combustion engines while stricter CO2 limits demand lower fuel consumption. Early closing of the intake valves (Miller timing) leads to reduced combustion temperatures due to lower effective compression ratio, and therefore lower formation and emission of nitrogen oxides. Miller timing is frequently used in gasoline engines, while in Diesel engines it competes with exhaust gas recirculation (EGR). When both measures are applied simultaneously, this may lead to increased emission of soot using standard Diesel fuel, as combustion temperature and oxygen content of the charge become too low. This work shows the investigation of different intake valve timings on an externally supercharged single-cylinder heavy-duty Diesel engine, stationary operated with hydrogenated vegetable oil (HVO), oxymethylene ether (OME), and standard Diesel fuel (DF). The synthetic fuels have a higher cetane number than DF, which supports ignition at lower temperatures. Moreover, OME has a soot-free combustion, which allows an extension of the operating limits without increased emissions. The results show that especially with Miller timing a high-performance turbocharging system is crucial, since higher boost pressure is required to compensate for the filling losses due to the earlier intake closing. The application of a high EGR rate is limited in this case, leading to a trade-off between Miller timing and EGR. All fuels show a reduction in nitrogen oxides of up to 40% with an improved efficiency of more than 3% at a typical road-load point. Measures to reduce ignition delay were found to be necessary, especially for DF. For OME, increased soot formation does not occur when combining Miller timing with low rail pressure, reduced boost pressure or EGR, which promotes simultaneous application of the measures resulting in minimized emissions of nitrogen oxides.

Igneous Fiber Reinforced Stealthy Armor for Submarine

2011 ◽  
Vol 332-334 ◽  
pp. 1955-1958
Author(s):  
Hua Wu Liu ◽  
Fan Jie Chu ◽  
Zong Bin Yang ◽  
Hong Ming Dai
Keyword(s):  
Experimental Data ◽  
Tensile Strength ◽  
Mathematical Models ◽  
High Performance ◽  
Honeycomb Structure ◽  
Heavy Duty ◽  
Working Temperature ◽  
Ultralow Temperature ◽  
Crystal Phases ◽  
Radar Wave

Abstract: Igneous gem is a modified mineral glass without devitrification during processing, which is far stronger than traditional basalt materials comprising both glass and crystal phases. Fiber made by igneous gem is an ideal reinforcement for the armor of submarine, with advantages such as infrared stealth (thermal insulation), sonar stealth (anti-vibration), radar stealth (transparent to radar wave), heavy duty anticorrosion, bullet-proof (theoretical tensile strength 15,000MPa), fire resistant (working temperature 910 oC) and ultralow temperature resistant (working temperature up to -269 oC), anti-aging and so on. The corresponding experimental data and mathematical models were demonstrated in this study and compared with other high performance materials. The honeycomb structure was proposed for the prefabricated composite and the advantages of such a material were thoroughly stated.

Additive Manufacturing of Hot Gas Path Parts and Engine Validation in a Heavy Duty GT

2016 ◽  
Author(s):  
Julius Schurb ◽  
Matthias Hoebel ◽  
Hartmut Haehnle ◽  
Harald Kissel ◽  
Laura Bogdanic ◽  
...  
Keyword(s):  
Additive Manufacturing ◽  
High Performance ◽  
Turbine Blades ◽  
Combustion Process ◽  
Heavy Duty ◽  
Hot Gas ◽  
Process Chains ◽  
Manufacturing Technologies ◽  
Cooling Air

Additive manufacturing and in particular Selective Laser Melting (SLM) are manufacturing technologies that can become a game changer for the production of future high performance hot gas path parts. SLM radically changes the design process giving unprecedented freedom of design and enabling a step change in part performance. Benefits are manifold, such as reduced cooling air consumption through more efficient cooling schemes, reduced emissions through better mixing in the combustion process and reduced cost through integrated part design. GE is already making use of SLM for its gas turbine components based on sound experience for new part production and reconditioning. The paper focuses on: a) Generic advantages of rapid manufacturing and design considerations for hot gas path parts b) Qualification of processes and additive manufacturing of engine ready parts c) SLM material considerations and properties validation d) Installation and validation in a heavy duty GT Additive Manufacturing (AM) of hot gas path components differs significantly from known process chains. All elements of this novel manufacturing route had to be established and validated. This starts with the selection of the powder alloy used for the SLM production and the determination of essential static and cyclic material properties. SLM specific design features and built-in functionality allow to simplify part assembly and to shortcut manufacturing steps. In addition, the post-SLM machining steps for engine ready parts will be described. As SLM is a novel manufacturing route, complementary quality tools are required to ensure part integrity. Powerful nondestructive methods, like 3D scanning and X-ray computer tomography have been used for that purpose. GE’s engine validation of SLM made parts in a heavy duty GT was done with selected hot gas path components in a rainbow arrangement including turbine blades with SLM tip caps. Although SLM has major differences to conventional manufacturing the various challenges from design to engine ready parts have been successfully mastered. This has been confirmed after the completion of the test campaign in 2015. All disassembled SLM components were found in excellent condition. Subsequent assessments of the SLM parts including metallurgical investigations have confirmed the good part condition.

High Performance Cutting of Aerospace Materials

2012 ◽  
Vol 498 ◽  
pp. 127-132 ◽  
Author(s):  
A. Krämer ◽  
Dieter Lung ◽  
Fritz Klocke
Keyword(s):  
High Performance ◽  
Physical And Mechanical Properties ◽  
Cryogenic Cooling ◽  
Process Stability ◽  
Aerospace Materials ◽  
Manufacturing Costs ◽  
High Temperature Alloys ◽  
Cutting Ceramics ◽  
Nickel Based Alloy ◽  
Cutting Speeds

Titanium and nickel-based alloys belong to the group of difficult-to-cut materials. The machining of these high-temperature alloys is characterized by low productivity and low process stability as a result of their physical and mechanical properties. Major problems during the machining of these materials are low applicable cutting speeds due to excessive tool wear, long machining times, and thus high manufacturing costs, as well as the formation of ribbon and snarled chips. Under these conditions automation of the production process is limited. This paper deals with strategies to improve machinability of titanium and nickel-based alloys. Using the example of the nickel-based alloy Inconel 718 high performance cutting with advanced cutting materials, such as PCBN and cutting ceramics, is presented. Afterwards the influence of different cooling strategies, like high-pressure lubricoolant supply and cryogenic cooling, during machining of TiAl6V4 is shown.

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