Optimization of Latency Insensitive Systems Through Back Pressure Minimization

Distributed joint congestion control and routing optimization has received a significant amount of attention recently. To date, however, most of the existing schemes follow a key idea called the back-pressure algorithm. Despite having many salient features, the first-order sub gradient nature of the back-pressure based schemes results in slow convergence and poor delay performance. To overcome these limitations, the present study was made as first attempt at developing a second-order joint congestion control and routing optimization framework that offers utility-optimality, queue-stability, fast convergence, and low delay. Contributions in this project are three-fold. The present study propose a new second-order joint congestion control and routing framework based on a primal-dual interior-point approach and established utility-optimality and queue-stability of the proposed second-order method. The results of present study showed that how to implement the proposed second-order method in a distributed fashion.

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Design and optimization of muffler back pressure

10.1063/5.0019700 ◽

2020 ◽

Author(s):

S. Thirumurugaveerakumar

Keyword(s):

Back Pressure ◽

Design And Optimization

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Experimental research on the performance of the forward variable area bypass injector for variable cycle engines

International Journal of Turbo and Jet Engines ◽

10.1515/tjeng-2020-0021 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Binglong Zhang ◽

He Liu ◽

Jianhua Zhou ◽

Hui Liu

Keyword(s):

Pressure Ratio ◽

Effective Means ◽

Experimental System ◽

Area Ratio ◽

Back Pressure ◽

Mode Transition ◽

Bypass Valve ◽

Injection Coefficient ◽

Bypass Ratio ◽

Specific Working

AbstractThe forward variable area bypass injector (FVABI) is a key component of double bypass variable cycle engine (VCE) to achieve mode transition and bypass ratio adjustment. In this paper, an experimental system for FVABI was constructed based on the analysis of relevant experimental theories, and then the experiments on FVABI were carried out for a specific working state in double bypass mode of VCE and for the comparison working states with different area ratios and different back pressure ratios. The results showed that the FVABI designed in this paper meets the requirements of VCE at this working state. The analysis of the influence of area ratio and back pressure ratio on the injection coefficient showed that the first bypass valve and back pressure were effective means to control the mass flow of FVABI.

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Numerical Investigation of Back Pressure and Acoustic Attenuation Performance of Two and Three Chamber Exhaust Muffler

Journal of Physics Conference Series ◽

10.1088/1742-6596/1850/1/012092 ◽

2021 ◽

Vol 1850 (1) ◽

pp. 012092

Author(s):

S Satish ◽

S Mohan Kumar

Keyword(s):

Numerical Investigation ◽

Back Pressure ◽

Acoustic Attenuation

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Cavitation patterns in high-pressure homogenization nozzles with cylindrical orifices: Influence of mixing stream in Simultaneous Homogenization and Mixing

Experimental and Computational Multiphase Flow ◽

10.1007/s42757-020-0088-9 ◽

2021 ◽

Author(s):

V. Gall ◽

E. Rütten ◽

H. P. Karbstein

Keyword(s):

High Pressure ◽

Process Design ◽

High Speed ◽

State Of The Art ◽

Back Pressure ◽

High Pressure Homogenization ◽

Unit Operation ◽

Mixing Chamber ◽

Cavitation Intensity ◽

Droplet Sizes

AbstractHigh-pressure homogenization is the state of the art to produce high-quality emulsions with droplet sizes in the submicron range. In simultaneous homogenization and mixing (SHM), an additional mixing stream is inserted into a modified homogenization nozzle in order to create synergies between the unit operation homogenization and mixing. In this work, the influence of the mixing stream on cavitation patterns after a cylindrical orifice is investigated. Shadow-graphic images of the cavitation patterns were taken using a high-speed camera and an optically accessible mixing chamber. Results show that adding the mixing stream can contribute to coalescence of cavitation bubbles. Choked cavitation was observed at higher cavitation numbers σ with increasing mixing stream. The influence of the mixing stream became more significant at a higher orifice to outlet ratio, where a hydraulic flip was also observed at higher σ. The decrease of cavitation intensity with increasing back-pressure was found to be identical with conventional high-pressure homogenization. In the future, the results can be taken into account in the SHM process design to improve the efficiency of droplet break-up by preventing cavitation or at least hydraulic flip.

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