Modular Bearing Designs to Cope With the New Engine Designs Demanding High Performance, Lead Free Solutions and Robustness

Author(s):  
Rainer Aufischer ◽  
Rick Walker ◽  
Martin Offenbecher ◽  
Gunther Hager

Engine development, driven by environmental considerations outlined in the different emission regulations, fuel economy and fuel availability in combination with economical boundary conditions, needs new approaches in bearing material and design. Since gas engines are gaining market share and firing pressures increase in Diesel engines in order to fulfill fuel economy a special focus has also been taken to tailor-made bearings for these applications. This complex task has to consider lining compound material strength and stability under different conditions like oil condition and dilution. Thin overlays with long term wear resistance and mixed friction capabilities as well as robust design for extraordinary events like dirt shock loading or adaptations at the engine start are necessary. To fulfill all these requirements different tasks have to be considered: 1. Bearing lining and steel shell compound to fulfill assembly requirements to combine a safe bearing seat with anti-fretting and high strength with base tribological characteristics 2. Design and use of different layers to compensate weakness of the one layer with the strength of another layer 3. Incorporation of special running conditions and cost reduction approaches in the layer design like polymer coatings for start stop and shaft designs with rougher surface finishes 4. Bearing design incorporating special shapes to cope better with deflections and geometric deficiencies of a special engine design or application In this publication existing and new lining compound approaches including lead free designs, a variety of different overlays from electroplated, polymer and sputtered ones are briefly described. Additionally it is explained how these layers are combined and how they work together to improve bearing performance. Testing of the bearing components and designs on bearing test rigs with new test conditions considering dirt shock and misalignment and their confirmation by engine running experiences are given for a gas engine and a high speed diesel engine applications. A special outlook on how this approach can be extended to other applications for the sake of robustness, cost reduction or performance increase will summarize the paper.

Author(s):  
Rainer Aufischer ◽  
Rick Walker ◽  
Martin Offenbecher ◽  
Gunther Hager

Engine development, driven by environmental considerations outlined in the different emission regulations, fuel economy, and fuel availability in combination with economical boundary conditions, needs new approaches in bearing material and design. Since gas engines are gaining market share and firing pressures increase in diesel engines in order to fulfill fuel economy, a special focus has also been taken to tailor-made bearings for these applications. This complex task has to consider lining compound material strength and stability under different conditions like oil condition and dilution. Thin overlays with long-term wear resistance and mixed friction capabilities as well as robust design for extraordinary events like dirt shock loading or adaptations at the engine start are necessary. To fulfill all these requirements, different tasks have to be considered: (1) bearing lining and steel shell compound to fulfill assembly requirements to combine a safe bearing seat with antifretting and high strength with base tribological characteristics, (2) design and use of different layers to compensate weakness of the one layer with the strength of another layer, (3) incorporation of special running conditions and cost reduction approaches in the layer design like polymer coatings for start stop and shaft designs with rougher surface finishes, and (4) bearing design incorporating special shapes to cope better with deflections and geometric deficiencies of a special engine design or application In this publication, existing and new lining compound approaches, including lead-free designs, a variety of different overlays from electroplated, polymer and sputtered ones, are briefly described. Additionally, it is explained how these layers are combined and how they work together to improve bearing performance. Testing of the bearing components and designs on bearing test rigs with new test conditions considering dirt shock and misalignment and their confirmation by engine running experiences are given for a gas engine and a high speed diesel engine applications. A special outlook on how this approach can be extended to other applications for the sake of robustness, cost reduction, or performance increase will summarize the paper.


Energies ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4144
Author(s):  
Yatai Ji ◽  
Paolo Giangrande ◽  
Vincenzo Madonna ◽  
Weiduo Zhao ◽  
Michael Galea

Transportation electrification has kept pushing low-voltage inverter-fed electrical machines to reach a higher power density while guaranteeing appropriate reliability levels. Methods commonly adopted to boost power density (i.e., higher current density, faster switching frequency for high speed, and higher DC link voltage) will unavoidably increase the stress to the insulation system which leads to a decrease in reliability. Thus, a trade-off is required between power density and reliability during the machine design. Currently, it is a challenging task to evaluate reliability during the design stage and the over-engineering approach is applied. To solve this problem, physics of failure (POF) is introduced and its feasibility for electrical machine (EM) design is discussed through reviewing past work on insulation investigation. Then the special focus is given to partial discharge (PD) whose occurrence means the end-of-life of low-voltage EMs. The PD-free design methodology based on understanding the physics of PD is presented to substitute the over-engineering approach. Finally, a comprehensive reliability-oriented design (ROD) approach adopting POF and PD-free design strategy is given as a potential solution for reliable and high-performance inverter-fed low-voltage EM design.


2014 ◽  
Vol 971-973 ◽  
pp. 1581-1585 ◽  
Author(s):  
Jun Liu ◽  
Yan Tian ◽  
Wei Hao ◽  
Lei Qu

In order to meet the request of high-speed data exchange in embedded systems, this paper details the high-speed SRIO (Serial RapidIO) interface protocol and the process of SRIO access timing between the local endpoint devices and the remote endpoint devices. And also we implement the design of the new high-performance RapidIO interconnection between DSP and FPGA. Through the performance testing of SRIO data transmission system, experimental results show that the design can stably transfer data at high speed between processors.


2011 ◽  
Vol 2011 ◽  
pp. 1-15 ◽  
Author(s):  
Alex Mutig ◽  
Dieter Bimberg

Progress of high-speed vertical cavity surface emitting lasers (VCSEL) operating around 980 nm is reviewed. A special focus is on their applications for future short-reach optical interconnects, for example, in high-performance computers (HPC). The wavelength of 980 nm has fundamental advantages for these applications and plays a significant role in VCSEL research today. The present data rates of 980 nm VCSELs exceed 40 Gbit/s, and excellent temperature stability has been reported. The major concepts leading to these impressive developments are presented.


Author(s):  
N. Yoshimura ◽  
K. Shirota ◽  
T. Etoh

One of the most important requirements for a high-performance EM, especially an analytical EM using a fine beam probe, is to prevent specimen contamination by providing a clean high vacuum in the vicinity of the specimen. However, in almost all commercial EMs, the pressure in the vicinity of the specimen under observation is usually more than ten times higher than the pressure measured at the punping line. The EM column inevitably requires the use of greased Viton O-rings for fine movement, and specimens and films need to be exchanged frequently and several attachments may also be exchanged. For these reasons, a high speed pumping system, as well as a clean vacuum system, is now required. A newly developed electron microscope, the JEM-100CX features clean high vacuum in the vicinity of the specimen, realized by the use of a CASCADE type diffusion pump system which has been essentially improved over its predeces- sorD employed on the JEM-100C.


Author(s):  
Marc H. Peeters ◽  
Max T. Otten

Over the past decades, the combination of energy-dispersive analysis of X-rays and scanning electron microscopy has proved to be a powerful tool for fast and reliable elemental characterization of a large variety of specimens. The technique has evolved rapidly from a purely qualitative characterization method to a reliable quantitative way of analysis. In the last 5 years, an increasing need for automation is observed, whereby energy-dispersive analysers control the beam and stage movement of the scanning electron microscope in order to collect digital X-ray images and perform unattended point analysis over multiple locations.The Philips High-speed Analysis of X-rays system (PHAX-Scan) makes use of the high performance dual-processor structure of the EDAX PV9900 analyser and the databus structure of the Philips series 500 scanning electron microscope to provide a highly automated, user-friendly and extremely fast microanalysis system. The software that runs on the hardware described above was specifically designed to provide the ultimate attainable speed on the system.


Author(s):  
M. T. Postek ◽  
A. E. Vladar

One of the major advancements applied to scanning electron microscopy (SEM) during the past 10 years has been the development and application of digital imaging technology. Advancements in technology, notably the availability of less expensive, high-density memory chips and the development of high speed analog-to-digital converters, mass storage and high performance central processing units have fostered this revolution. Today, most modern SEM instruments have digital electronics as a standard feature. These instruments, generally have 8 bit or 256 gray levels with, at least, 512 × 512 pixel density operating at TV rate. In addition, current slow-scan commercial frame-grabber cards, directly applicable to the SEM, can have upwards of 12-14 bit lateral resolution permitting image acquisition at 4096 × 4096 resolution or greater. The two major categories of SEM systems to which digital technology have been applied are:In the analog SEM system the scan generator is normally operated in an analog manner and the image is displayed in an analog or "slow scan" mode.


Author(s):  
Sai Venkatramana Prasada G.S ◽  
G. Seshikala ◽  
S. Niranjana

Background: This paper presents the comparative study of power dissipation, delay and power delay product (PDP) of different full adders and multiplier designs. Methods: Full adder is the fundamental operation for any processors, DSP architectures and VLSI systems. Here ten different full adder structures were analyzed for their best performance using a Mentor Graphics tool with 180nm technology. Results: From the analysis result high performance full adder is extracted for further higher level designs. 8T full adder exhibits high speed, low power delay and low power delay product and hence it is considered to construct four different multiplier designs, such as Array multiplier, Baugh Wooley multiplier, Braun multiplier and Wallace Tree multiplier. These different structures of multipliers were designed using 8T full adder and simulated using Mentor Graphics tool in a constant W/L aspect ratio. Conclusion: From the analysis, it is concluded that Wallace Tree multiplier is the high speed multiplier but dissipates comparatively high power. Baugh Wooley multiplier dissipates less power but exhibits more time delay and low PDP.


Nanophotonics ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 937-945
Author(s):  
Ruihuan Zhang ◽  
Yu He ◽  
Yong Zhang ◽  
Shaohua An ◽  
Qingming Zhu ◽  
...  

AbstractUltracompact and low-power-consumption optical switches are desired for high-performance telecommunication networks and data centers. Here, we demonstrate an on-chip power-efficient 2 × 2 thermo-optic switch unit by using a suspended photonic crystal nanobeam structure. A submilliwatt switching power of 0.15 mW is obtained with a tuning efficiency of 7.71 nm/mW in a compact footprint of 60 μm × 16 μm. The bandwidth of the switch is properly designed for a four-level pulse amplitude modulation signal with a 124 Gb/s raw data rate. To the best of our knowledge, the proposed switch is the most power-efficient resonator-based thermo-optic switch unit with the highest tuning efficiency and data ever reported.


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