scholarly journals Analysis of accelerated methods testing piston engine for reliability

2021 ◽  
Vol 1086 (1) ◽  
pp. 012006
Author(s):  
A N Gots ◽  
Sh A Amirseyidov
Keyword(s):  
Piston Engine ◽  
Accelerated Methods

INJECTION SYSTEM ANALYSIS FOR A VARIABLE COMPRESSION ROTARY-PISTON ENGINE

2019 ◽  
Author(s):  
Lucas Melo Queiroz Barbosa ◽  
Lucas Tannús ◽  
Alexandre Zuquete Guarato
Keyword(s):  
System Analysis ◽  
Injection System ◽  
Piston Engine ◽  
Variable Compression

Research on sealing characteristics of annular power cylinder based on twin-rotor piston engine

2021 ◽  
pp. 095440622110214
Author(s):  
Dibo Pan ◽  
Haijun Xu ◽  
Bolong Liu ◽  
Congnan Yang
Keyword(s):  
Compression Ratio ◽  
Simulation Analysis ◽  
Piston Engine ◽  
Leakage Model ◽  
Gas Leakage ◽  
Power Cylinder ◽  
Sealing Performance ◽  
Piston Seal ◽  
Realization Process ◽  
Twin Rotor

The sealing characteristics of an annular power cylinder based on the Twin-rotor piston engine are studied, which provides a theoretical foundation for the sealing design of a new high-power density piston engine. In this paper, the basis thermodynamic realization process of an annular power cylinder is presented. The Runge Kutta equation is used to establish the coupled leakage model of adjacent working chambers under annular piston seal. And the sealing performance of the annular power cylinder is analyzed in detail. Moreover, the influence of rotor speed and compression ratio on the sealing characteristics and leakage is studied. Finally, some tests are carried out to verify the sealing principle and simulation results, which verifies the theoretical basis of simulation analysis. Results show that there are double pressure peaks in the leakage chamber between two working chambers, which is beneficial to reduce the leakage rate. Besides, increasing the speed and decreasing the compression ratio can help to reduce gas leakage. Furthermore, the effects of speed variation on the leakage are only significant when rotating at low speed. Changing the compression ratio has a greater effect on the slope of the leakage curve at a low compression ratio, and the lower the compression ratio, the better the sealing effect.

scholarly journals Research on the Operating Characteristics of Hydraulic Free-Piston Engines: A Systematic Review and Meta-Analysis

Energies ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3530
Author(s):  
Fukang Ma ◽  
Shuanlu Zhang ◽  
Zhenfeng Zhao ◽  
Yifang Wang
Keyword(s):  
Systematic Review ◽  
High Efficiency ◽  
Meta Analysis ◽  
Combustion Process ◽  
Research Progress ◽  
Future Research ◽  
Operating Characteristics ◽  
Piston Engine ◽  
Free Piston ◽  
Free Piston Engine

The hydraulic free-piston engine (HFPE) is a kind of hybrid-powered machine which combines the reciprocating piston-type internal combustion engine and the plunger pump as a whole. In recent years, the HFPE has been investigated by a number of research groups worldwide due to its potential advantages of high efficiency, energy savings, reduced emissions and multi-fuel operation. Therefore, our study aimed to assess the operating characteristics, core questions and research progress of HFPEs via a systematic review and meta-analysis. We included operational control, starting characteristics, misfire characteristics, in-cylinder working processes and operating stability. We conducted the literature search using electronic databases. The research on HFPEs has mainly concentrated on four kinds of free-piston engine, according to piston arrangement form: single piston, dual pistons, opposed pistons and four-cylinder complex configuration. HFPE research in China is mainly conducted in Zhejiang University, Tianjin University, Jilin University and the Beijing Institute of Technology. In addition, in China, research has mainly focused on the in-cylinder combustion process while a piston is free by considering in-cylinder combustion machinery and piston dynamics. Regarding future research, it is very important that we solve the instabilities brought about by chance fluctuations in the combustion process, which will involve the hydraulic system’s efficiency, the cyclical variation, the method of predicting instability and the recovery after instability.

Facile syringe filter-enabled bacteria separation, enrichment, and buffer exchange for clinical isolation-free digital detection and characterization of bacterial pathogens in urine

The Analyst ◽  
2021 ◽  
Author(s):  
Pengfei Zhang ◽  
Aniruddha Kaushik ◽  
Kathleen E Mach ◽  
Kuangwen Hsieh ◽  
Joseph C. Liao ◽  
...  
Keyword(s):  
Infectious Diseases ◽  
Antibiotic Therapy ◽  
Broad Spectrum ◽  
Antimicrobial Susceptibility ◽  
Susceptibility Testing ◽  
Evidence Based ◽  
Pathogen Identification ◽  
Accelerated Methods ◽  
Syringe Filter

The development of accelerated methods for pathogen identification (ID) and antimicrobial susceptibility testing (AST) for infectious diseases is necessary to facilitate evidence-based antibiotic therapy and reduce clinical overreliance on broad-spectrum...

scholarly journals Decentralized and parallel primal and dual accelerated methods for stochastic convex programming problems

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Darina Dvinskikh ◽  
Alexander Gasnikov
Keyword(s):  
Convex Optimization ◽  
Inverse Problems ◽  
Convex Programming ◽  
Data Science ◽  
Optimization Problems ◽  
Stochastic Gradient ◽  
Logarithmic Factor ◽  
Accelerated Methods ◽  
Convex Optimization Problems ◽  
Primal And Dual

Abstract We introduce primal and dual stochastic gradient oracle methods for decentralized convex optimization problems. Both for primal and dual oracles, the proposed methods are optimal in terms of the number of communication steps. However, for all classes of the objective, the optimality in terms of the number of oracle calls per node takes place only up to a logarithmic factor and the notion of smoothness. By using mini-batching technique, we show that the proposed methods with stochastic oracle can be additionally parallelized at each node. The considered algorithms can be applied to many data science problems and inverse problems.

Research on the Turbocharger Technology of Piston Aircraft Engine

2013 ◽  
Vol 457-458 ◽  
pp. 531-535
Author(s):  
Zhong Jian Pan ◽  
Qing Hua He ◽  
Yong Guo ◽  
Yu Ming Zhao ◽  
Jing Yang
Keyword(s):  
Simulation Model ◽  
High Altitude ◽  
Gas Flow ◽  
State Power ◽  
Aircraft Engine ◽  
Cylinder Pressure ◽  
Piston Engine ◽  
Ground Condition

The supercharger technology of piston aviation engine determines its flight capabilities, and then establishes a turbocharger simulation model of an aviation piston engine. After simulating the engine ground features and 5000-meter altitude characteristics, and comparing the efficiency of compressor and turbocharger in different environments, after the installation of mechanical supercharger, gas flow has been improved, the cylinder pressure decreased about 10% compared with ground condition and engine altitude state power is restored, even 20,000 feet Power restored to 80%, which can meet the needs of high-altitude flight.

Sign in / Sign up

Export Citation Format

Share Document