Investigation of late fuel injection position on the combustion of free piston engine

2018 ◽  
Author(s):  
Salah E. Mohammed ◽  
N. A. Ramlan ◽  
A. Rashid A. Aziz ◽  
F. Firmansyah ◽  
Z. Ezrann Zainal
Keyword(s):  
Fuel Injection ◽  
Piston Engine ◽  
Free Piston ◽  
Free Piston Engine

Study on the Motion Characteristics of a Hydraulic Free-Piston Engine

2014 ◽  
Vol 889-890 ◽  
pp. 390-393
Author(s):  
Shi Yu Li ◽  
Zhao Cheng Yuan ◽  
Jia Yi Ma
Keyword(s):  
Fuel Injection ◽  
Fuel Efficiency ◽  
Injection Timing ◽  
Piston Engine ◽  
Free Piston ◽  
Fuel Injection Timing ◽  
Free Piston Engine ◽  
Center Position ◽  
Working Frequency ◽  
Motion Characteristics

Hydraulic free-piston engines have potential advantages of cost and fuel efficiency. Due to no crankshaft system, it is difficult and important to control the piston motion and working frequency precisely. This paper studies on the motion characteristics for the hydraulic free-piston engine effects of operation parameters, and results are presented. The TDC (Top Dead Center) position and CR (Compression Ration) are great influenced by starting pressure and fuel injection timing, and working frequency is mainly influenced by piston mass, starting pressure and fuel quantity.

Research on Hydraulic Free Piston Engine with High Scavenging Efficiency

2015 ◽  
Vol 779 ◽  
pp. 187-191
Author(s):  
Hao Ling Ren ◽  
Tian Liang Lin ◽  
Hai Bo Xie
Keyword(s):  
Diesel Engine ◽  
Fuel Injection ◽  
Injection System ◽  
Fuel Injection System ◽  
Piston Engine ◽  
Free Piston ◽  
The Poor ◽  
Free Piston Engine ◽  
Scavenging Efficiency ◽  
Stroke Engine

The poor scavenging process of the hydraulic free piston engine which uses two-stroke engine as its driver was presented. A two-cylinder, four-stroke diesel engine was proposed to drive the single-piston hydraulic free piston engine to improve the scavenging process. The intake and release valves mechanism and fuel injection system were redesigned to adapt the performance of the single-piston hydraulic free piston engine. Feasibility and reliability of this new structure are verified through simulation.

Motion Characteristics and Influence Factors of Piston Assembly in a Compression-Ignition Hydraulic Free-Piston Engine

2013 ◽  
Vol 860-863 ◽  
pp. 1761-1765
Author(s):  
Ying Xiao Yu ◽  
Zhao Cheng Yuan ◽  
Jia Yi Ma ◽  
Shi Yu Li
Keyword(s):  
Fuel Injection ◽  
Influence Factors ◽  
Basic Structure ◽  
Injection Timing ◽  
Compression Ignition ◽  
Piston Engine ◽  
Free Piston ◽  
Free Piston Engine ◽  
Motion Characteristics ◽  
Piston Assembly

The advantages and basic structure of hydraulic free-piston engine (HFPE) were presented. And the operation principle of a single piston compression-ignition HFPE was analyzed. Based on the basic theory of thermodynamics, hydraulic fluid mechanics and dynamics, the system simulation model for a single-piston compression-ignition HFPE was established in the environment of MATLAB/SIMULINK. The simulation results, which accord with the related literature data, indicate that the asymmetric characteristics of piston motion in the entire cycle are very obvious, the compression stroke duration is longer than the expansion stroke, the time at around the top dead center (TDC) is short. The piston assembly motion is a process when the energy balance is fulfilled, and some factors must be taken into account for design optimization, such as the piston assembly mass, compression accumulator pressure, fuel injection timing and fuel injection quantity.

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.

Free-Piston Compressor-Engines

1947 ◽  
Vol 156 (1) ◽  
pp. 253-271 ◽  
Author(s):  
H. O. Farmer
Keyword(s):  
Fuel Injection ◽  
Piston Compressor ◽  
Gas Generator ◽  
Compression Pressure ◽  
Compression Ignition Engine ◽  
Free Piston ◽  
Alternative Scheme ◽  
Free Piston Engine ◽  
New Type ◽  
Commercial Work

The Pescara free-piston engine has been developed in France during the last twenty years, and the paper gives a description of a portable air compressor which has been proved in commercial work, and is now in production. An explanation is given of those characteristics in which this engine differs from the orthodox engine-driven crankshaft compressor. The power unit is an opposed-piston two-stroke compression-ignition engine, the compressor piston being directly attached to one of the engine pistons, while the cushion piston is directly attached to the other. The cushion piston gives stability, ensures that the energy available for the return stroke is constant for any conditions of operation, and thus gives a constant compression pressure in the combustion cylinder. The velocity characteristics of the pistons during the inward and outward strokes are described with their effect on the compressor and other sections. The fuel injection gear and also an alternative scheme is described; and indicator diagrams show the results obtained. The output of the compressor is controlled by the governor; the governor controls the fuel injected and thus determines the stroke of the pistons and thereby the quantity of air delivered. The efficiency of the combustion section is given, with the specific fuel consumption loop of the compressor as a whole. Methods of starting, by use of a spring or compressed air, are given to illustrate the characteristics dealt with. The development of the free-piston compressor has led to the development of the power gas-generator, in which the combination of free-piston compressor and turbine forms a new type of prime mover.

Sign in / Sign up

Export Citation Format

Share Document