Design and Analysis of Rotary Positive Displacement Mechanism for Oil-Less Compression

2010 ◽  
Author(s):  
Holger Roser
Keyword(s):  
High Speed ◽  
High Performance ◽  
Effective Means ◽  
Cost Effective ◽  
Industrial Applications ◽  
Two Phase ◽  
Major Drawback ◽  
Displacement Mechanism ◽  
Flow Losses ◽  
Positive Displacement

In this paper, a simple positive displacement mechanism is investigated, which comprises two counter-rotating meshing rotors within a casing. Although considered for various applications more than a century ago, the basic geometry of this mechanism has not been further explored or adapted to modern gas compressor technology. As a fully balanced rotational mechanism operating at uniform angular velocity, potential applications range from pumps to expanders, from slow large displacement to high-speed devices; nonetheless, this research focuses on high-performance oil-less gas compressors as an ideal application. During one complete cycle, the main rotor compresses and discharges the fluid, whilst the secondary rotor seals the compression chamber. Important features of this mechanism are the circular profiles of the rotors, the potential to accommodate large ports for reduced flow losses, and ease of cooling. The simple geometry facilitates a cost-effective means of achieving tight operating clearances between rotors and casing for enhanced sealing without the need for liquid lubricants such as oil. This study and preliminary tests indicate that pressure ratios suitable for standard industrial applications can be obtained over a broad speed range, whilst minimizing friction and flow losses, a major drawback of current technologies. Moreover, two-phase compression and injection of liquids prior to compression have been studied and identified as a means to further improve efficiency and cooling.

Parallel Computing for Tire Simulations

2011 ◽  
Vol 39 (3) ◽  
pp. 193-209 ◽  
Author(s):  
H. Surendranath ◽  
M. Dunbar
Keyword(s):  
High Performance ◽  
Effective Means ◽  
Cost Effective ◽  
Turnaround Time ◽  
Careful Consideration ◽  
Rolling Contact ◽  
Element Analysis ◽  
Parallel Solvers ◽  
Design Changes ◽  
Highly Nonlinear

Abstract Over the last few decades, finite element analysis has become an integral part of the overall tire design process. Engineers need to perform a number of different simulations to evaluate new designs and study the effect of proposed design changes. However, tires pose formidable simulation challenges due to the presence of highly nonlinear rubber compounds, embedded reinforcements, complex tread geometries, rolling contact, and large deformations. Accurate simulation requires careful consideration of these factors, resulting in the extensive turnaround time, often times prolonging the design cycle. Therefore, it is extremely critical to explore means to reduce the turnaround time while producing reliable results. Compute clusters have recently become a cost effective means to perform high performance computing (HPC). Distributed memory parallel solvers designed to take advantage of compute clusters have become increasingly popular. In this paper, we examine the use of HPC for various tire simulations and demonstrate how it can significantly reduce simulation turnaround time. Abaqus/Standard is used for routine tire simulations like footprint and steady state rolling. Abaqus/Explicit is used for transient rolling and hydroplaning simulations. The run times and scaling data corresponding to models of various sizes and complexity are presented.

Review on modification strategies of polyethylene/polypropylene immiscible thermoplastic polymer blends for enhancing their mechanical behavior

2018 ◽  
Vol 51 (4) ◽  
pp. 291-336 ◽  
Author(s):  
Antimo Graziano ◽  
Shaffiq Jaffer ◽  
Mohini Sain
Keyword(s):  
High Performance ◽  
Cost Effective ◽  
Good Method ◽  
Waste Recycling ◽  
Industrial Applications ◽  
Polymer Waste ◽  
Reactive Compatibilization ◽  
Brittle To Ductile Transition ◽  
Commercial Applications ◽  
Effective Product

Blends of polyethylene (PE) and polypropylene (PP) have always been the subject of intense reasearch for encouraging polymer waste recycling while producing new materials for specific applications in a sustainable way. However, being thermodynamically immiscible, these polyolefins form a binary system usually exhibiting lower performances compared with those of the homopolymers. Many studies have been carried out to better understand the PE/PP blend compatibilization for developing a high-performance and cost-effective product. Both nonreactive and reactive compatibilization promote the brittle to ductile transition for a PE/PP blend. However, the final product usually does not meet the requirements for high demanding commercial applications. Therefore, further PE/PP modification with a reinforcing filler, being either synthetic or natural, proved to be a good method for manufacturing high-performance reinforcend polymer blend composites, with superior and tailored properties. This review summarizes the recent progress in compatibilization techniques applied for enhancing the interfacial adhesion between PE and PP. Moreover, future perspectives on better understanding the influence of themodynamics on PE/PP synergy are discussed to introduce more effective compatibilization strategies, which will allow this blend to be used for innovative industrial applications.

Age-Related Differences in Throwing Techniques Used by the Catcher in Baseball

1994 ◽  
Vol 6 (3) ◽  
pp. 225-235 ◽  
Author(s):  
Shinji Sakurai ◽  
Bruce Elliott ◽  
J. Robert Grove
Keyword(s):  
High Speed ◽  
High Performance ◽  
Age Groups ◽  
Three Dimensional ◽  
Transformation Method ◽  
High Speed Photography ◽  
Two Phase ◽  
Ball Speed ◽  
Age Related ◽  
Release Speed

Three-dimensional (3-D) high speed photography was used to record the overarm throwing actions of five open-age, four 18-year-old, six 16-year- old, and six 14-year-old high-performance baseball catchers. The direct linear transformation method was used for 3-D space reconstruction from 2-D images of the catchers throwing from home plate to second base recorded using two phase-locked cameras operating at a nominal rate of 200 Hz. Selected physical capacity measures were also recorded and correlated with ball release speed. In general, anthropometric and strength measures significantly increased through the 14-year-old to open-age classifications, while a range of correlation coefficients from .50 to .84 was recorded between these physical capacities and ball speed at release. While many aspects of the kinematic data at release were similar, the key factors of release angle and release speed varied for the different age groups.

scholarly journals High-speed high-resolution laser diode-based photoacoustic microscopy for in vivo microvasculature imaging

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Xiufeng Li ◽  
Victor T C Tsang ◽  
Lei Kang ◽  
Yan Zhang ◽  
Terence T W Wong
Keyword(s):  
High Resolution ◽  
High Speed ◽  
High Performance ◽  
Continuous Wave ◽  
Signal To Noise Ratio ◽  
Cost Effective ◽  
High Signal ◽  
Photoacoustic Microscopy ◽  
Mouse Ear

AbstractLaser diodes (LDs) have been considered as cost-effective and compact excitation sources to overcome the requirement of costly and bulky pulsed laser sources that are commonly used in photoacoustic microscopy (PAM). However, the spatial resolution and/or imaging speed of previously reported LD-based PAM systems have not been optimized simultaneously. In this paper, we developed a high-speed and high-resolution LD-based PAM system using a continuous wave LD, operating at a pulsed mode, with a repetition rate of 30 kHz, as an excitation source. A hybrid scanning mechanism that synchronizes a one-dimensional galvanometer mirror and a two-dimensional motorized stage is applied to achieve a fast imaging capability without signal averaging due to the high signal-to-noise ratio. By optimizing the optical system, a high lateral resolution of 4.8 μm has been achieved. In vivo microvasculature imaging of a mouse ear has been demonstrated to show the high performance of our LD-based PAM system.

Study on structure optimization of a bubble cap against erosion wear of an S Zorb desulfurization reactor distribution plate

2021 ◽  
pp. 095440892110424
Author(s):  
HZ Jin ◽  
SQ Gao ◽  
HL Zhao ◽  
C Wang ◽  
GF Ou
Keyword(s):  
High Speed ◽  
Effective Means ◽  
Structure Optimization ◽  
Erosion Wear ◽  
Particle Erosion ◽  
Two Phase ◽  
Wear Area ◽  
Inner Diameter ◽  
Distribution Plate ◽  
Semi Empirical

Bubble cap structures are researched for the particle erosion wear of the distribution plate (tray for short) in an S Zorb desulfurization reactor. The semi-empirical model of erosion wear prediction of gas–solid two-phase flow is revised by means of erosion wear experiments at high temperature and high speed. According to the revised erosion wear, the influence of the h0 (the distance from the bottom of the bubble cap to the tray), h1 (distance from the outlet of the lifting pipe to the top of the bubble cap interface), N (the number of cavities), d0 (the inner diameter of bubble cap) on erosion wear of trays are studied. The results show that a smaller h0 will make the erosion degree of the tray more serious; it is recommended to keep h0 = 17 mm. A larger h1 will alleviate the erosion wear degree of adsorbent particles on the tray, but considering the efficiency of the reaction, h1 = 36 mm is more appropriate. The increase of N reduces the erosion wear less but enhances the fluid disturbance and makes the erosion wear area unstable; so, N should be kept at 10. The increase of d0 reduces the velocity and density of fluid impacting the tray, thus reducing the erosion wear degree, which is an effective means.

Light Rail Lite or Cost-Effective Improvements to Bus Service?

2005 ◽  
Vol 1927 (1) ◽  
pp. 22-30 ◽  
Author(s):  
Daniel B. Hess ◽  
Brian D. Taylor ◽  
Allison C. Yoh
Keyword(s):  
High Speed ◽  
Low Cost ◽  
Effective Means ◽  
Cost Effective ◽  
Light Rail ◽  
Rapid Transit ◽  
Service Characteristics ◽  
Wide Range ◽  
Bus Service ◽  
The Cost

Bus rapid transit (BRT) is growing rapidly in popularity because it is viewed widely as an efficient and effective means to improve both transit service and patronage. This paper argues that two distinct views of BRT are emerging: ( a) BRT as a new form of high-speed, rubber-tired, rail-like rapid transit and ( b) BRT as a cost-effective way to upgrade both the quality and image of traditional fixed-route bus service. These two views carry different price tags because the cost of planning, constructing, and operating BRT depends on the complexity of new service features and on rises for BRT that offer service characteristics approaching those of light rail. This study fills a gap in the literature on the costs of BRT by examining in detail component costs–-actual costs for recently implemented services and projected costs for planned new services–-for a sample of BRT systems in North American cities. The study examined BRT costs of 14 planned and recently opened BRT systems to determine how the wide range of BRT service and technology configurations affect costs. The study found that although some of the most successful and popular new BRT systems are high-quality services operating in mixed traffic and implemented at relatively low cost, most BRT projects on the drawing boards are more elaborate, more expensive systems than many currently in service. Most new BRT projects emphasize elaborate LRT-type improvements to lines and stations in one or a few corridors rather than less splashy improvements (such as next-bus monitors, signal preemption, queue-jump lanes, and so forth) affecting more lines and modes in local transit networks. Among the 14 systems examined here, most could be characterized as light rail lite.

scholarly journals Systematic Separation and Purification of Alkaloids from Euchresta tubulosa Dunn. by Various Chromatographic Methods

Processes ◽  
2019 ◽  
Vol 7 (12) ◽  
pp. 924
Author(s):  
Wei-Xin Li ◽  
Huan Wang ◽  
Ai-Wen Dong
Keyword(s):  
Natural Products ◽  
Silica Gel ◽  
Column Chromatography ◽  
High Speed ◽  
High Performance ◽  
Ionization Mass ◽  
Separation And Purification ◽  
Two Phase ◽  
Rapid Separation ◽  
Chemical Structures

High-speed countercurrent chromatography (HSCCC) and silica gel column chromatography were used to separate and purify alkaloids from Chinese herbal medicine Euchresta tubulosa Dunn. The purpose of this study is to provide a system mode for rapid separation of alkaloids from natural products. In the experiment, the eluent of silica gel column chromatography was screened by thin layer chromatography (TLC) to obtain four components with different polarity. Then, the two-phase solvent systems of different components were selected and purified by HSCCC. Four alkaloids with relatively high content were obtained by this mode successfully, including matrine (28 mg), oxymatrine (32 mg), N-formyl cytisine (24 mg), and cytisine (58 mg). The purity was higher than 91% by high performance liquid chromatography–ultraviolet (HPLC-UV) and their chemical structures were identified by nuclear magnetic resonance (NMR) and electron ionization mass spectrometry (EI-MS). The results showed that the combination of HSCCC and silica gel column chromatography could make alkaloids from natural products separate systematically.

Dual Die Package Design Strategy and Performance

2005 ◽  
Author(s):  
Mahadevan Suryakumar ◽  
Lu-Vong T. Phan ◽  
Mathew Ma ◽  
Wajahat Ahmed
Keyword(s):  
Power Efficiency ◽  
High Speed ◽  
High Performance ◽  
Clock Cycle ◽  
Average Power ◽  
Cost Effective ◽  
Design Strategy ◽  
Leakage Power ◽  
Memory Accesses ◽  
And Performance

The alarming growth of power increase has presented numerous packaging challenges for high performance processors. The average power consumed by a processor is the sum of dynamic and leakage power. The dynamic power is proportional to V^2, while the leakage current (therefore leakage power) is proportional to V^b where V is the voltage and b>1 for modern processes. This means lowering voltage reduces energy consumed per clock cycle but reduces the maximum frequency at which the processor can operate at. Since reducing voltage reduces power faster than it does frequency, integrating more cores into the processor would result in better performance/power efficiency but would generate more memory accesses, driving a need for larger cache and high speed signaling [1]. In addition, the design goal to create unified package pinout for both single core and multicore product flavors adds additional constraint to create a cost effective package solution for both market segments. This paper discusses the design strategy and performance of dual die package to optimize package performance for cost.

scholarly journals Regioselective Hydroxylation of Rhododendrol by CYP102A1 and Tyrosinase

Catalysts ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1114
Author(s):  
Chan Mi Park ◽  
Hyun Seo Park ◽  
Gun Su Cha ◽  
Ki Deok Park ◽  
Chul-Ho Yun
Keyword(s):  
Lung Cancer ◽  
Ascorbic Acid ◽  
High Performance ◽  
Cost Effective ◽  
Industrial Applications ◽  
Ortho Position ◽  
Oxidation Reactions ◽  
Naturally Occurring ◽  
Regioselective Hydroxylation ◽  
Catalyzed Reactions

Rhododendrol (RD) is a naturally occurring phenolic compound found in many plants. Tyrosinase (Ty) converts RD to RD-catechol and subsequently RD-quinone via two-step oxidation reactions, after which RD-melanin forms spontaneously from RD-quinone. RD is cytotoxic in melanocytes and lung cancer cells, but not in keratinocytes and fibroblasts. However, the function of RD metabolites has not been possible to investigate due to the lack of available high purity metabolites. In this study, an enzymatic strategy for RD-catechol production was devised using engineered cytochrome P450 102A1 (CYP102A1) and Ty, and the product was analyzed using high-performance liquid chromatography (HPLC), LC-MS, and NMR spectroscopy. Engineered CYP102A1 regioselectively produced RD-catechol via hydroxylation at the ortho position of RD. Although RD-quinone was subsequently formed by two step oxidation in Ty catalyzed reactions, L-ascorbic acid (LAA) inhibited RD-quinone formation and contributed to regioselective production of RD-catechol. When LAA was present, the productivity of RD-catechol by Ty was 5.3-fold higher than that by engineered CYP102A1. These results indicate that engineered CYP102A1 and Ty can be used as effective biocatalysts to produce hydroxylated products, and Ty is a more cost-effective biocatalyst for industrial applications than engineered CYP102A1.

scholarly journals Preparative Purification of Recombinant Proteins: Current Status and Future Trends

2013 ◽  
Vol 2013 ◽  
pp. 1-18 ◽  
Author(s):  
Mayank Saraswat ◽  
Luca Musante ◽  
Alessandra Ravidá ◽  
Brian Shortt ◽  
Barry Byrne ◽  
...  
Keyword(s):  
High Performance ◽  
Cost Effective ◽  
Downstream Processing ◽  
Current Status ◽  
Comprehensive Overview ◽  
Two Phase ◽  
Phase Partitioning ◽  
Absolute Requirement ◽  
Flow Filtration ◽  
Selection Of

Advances in fermentation technologies have resulted in the production of increased yields of proteins of economic, biopharmaceutical, and medicinal importance. Consequently, there is an absolute requirement for the development of rapid, cost-effective methodologies which facilitate the purification of such products in the absence of contaminants, such as superfluous proteins and endotoxins. Here, we provide a comprehensive overview of a selection of key purification methodologies currently being applied in both academic and industrial settings and discuss how innovative and effective protocols such as aqueous two-phase partitioning, membrane chromatography, and high-performance tangential flow filtration may be applied independently of or in conjunction with more traditional protocols for downstream processing applications.

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