Abstract Recently, cellulosic materials have been considered as a useful resource for the recovery of valuable chemicals and liquid fuels, etc. Cellulose is homopolymer D ‐glucose, which often used model compound biomass. Reactions ‐glucose in subcritical water reaction solvent were conducted using single‐flow‐type reactor ( S1 ) an admixture‐type with feed preheated‐water flow S2 at temperatures from 200 to 240 °C, pressures 15 20 MPa, residence times 40 120 s, initial concentrations 1.5–10...

This study aims to utilize high-pressure split-main injection for improving the thermal efficiency of diesel engines.A series experiments was conducted using a single-cylinder engine under conditions an speed 2,250 rpm and gross indicated mean effective pressure 1.43 MPa.The varied in range 160-270 MPa.Split-main applied reduce cooling loss condition high pressure, split ratio number stages were varied.The dwell main set near-zero order minimize elongation total duration.As result, improved...

The aim of this study is to find strategies for fully utilizing the advantage diesel-ethanol blend fuel in recent diesel engines. For purpose, experiments were performed using a single-cylinder direct injection engine equipped with high-pressure common rail and cold EGR system. results indicate that significant PM reduction at high loads can be achieved 15% ethanol-diesel fuel. Increasing pressure promotes reduction. However, poor ignitability ethanol blended higher rate rise unstable...

Numerical calculations were carried out to investigate the formation of a fuel–air mixture as well ignition and combustion processes associated with diesel spray impinging on wall. This was performed by modeling formed injecting n-heptane into constant-volume vessel under high temperature pressure, fuel droplets described discrete droplet model. The flow turbulent diffusion calculated based large eddy simulation method simulate local non-homogeneous accompanying heat release. flame structure...

Temporal variations of a two-dimensional distribution velocities in nitrogen jet and methane-jet flame are measured by cross-correlation particle-image velocimetry (PIV). Two different approaches to investigating the turbulence characteristics demonstrated. One gives ensemble-averaged intensities means repetitive PIV measurements using double-pulse laser for longer period. The other provides detailed motion velocity profiles shorter duration, allowing one analyse characteristic scale...

In film cooling approaches, a of liquid fuel is formed on the chamber wall bipropellant thrusters to protect from high-temperature combustion gases. To optimize amount required sufficiently cool in this manner without degrading performance thrusters, formation process needs be understood. end, study, factors affecting spread were experimentally investigated. particular, experimental apparatus that could reproduce state jet being injected onto form was developed. Water used as test because...

To examine the feasibility of improving performance through highly flexible fuel injection, a series experiments were performed using single-cylinder diesel engine with dual injector system, which included two sets common-rail injection systems. The injectors installed around center cylinder to simulate single nozzle configuration. This system enabled different rates in each pulse and wide dwell range between pulses, i.e., even negative could be performed. Experiments multi-stage conducted...

Abstract The flow of a high‐speed unsteady jet is analyzed using computational fluid dynamics for an incompressible with the k –ε turbulence model. pseudo‐nozzle concept applied to inlet condition large pressure gradient. results show that time history development agrees experimental data methane and hydrogen fuels. In addition, effect injection on tip well described this Furthermore, effects conditions intensity scale are investigated. © 2006 Wiley Periodicals, Inc. Heat Trans Asian Res,...

A series of experiments was conducted using a singlecylinder small-bore (85 mm) diesel engine to investigate the smoke-reduction effect post injection by varying number nozzle orifices and pressure.The were performed under constant quantity condition fixed NOx emission condition.The results indicated that smoke six-hole, sevenhole, eight-hole nozzles decreased for advanced injection, except 10-hole increased as from moderately late timing around 17 ATDC.However, 10hole with higher pressure...

In order to extend the available load range and obtain higher thermal efficiency in natural gas premixed charge compression ignition (PCCI) engines, a strategy for controlling direct injection combustion is discussed. Experimental results from single-cylinder engine tests demonstrate possibility by fuel injection. Reduced nozzle orifice size reduced angle provide efficiency; however, this promotes tendency knock because of formation locally rich mixture. Arising discussions based on...

An auto-ignition process of non-homogeneous mixture was fundamentally investigated using a numerical calculation based on the chemical kinetics and stochastic approach. In present study, n-heptane is calculated reduced mechanism developed by Seiser et al. The non-uniform states turbulent mixing are statistically described probability density functions method, which originally Curl's model. results show that starting points low temperature oxidation ignition delay period hardly affected...

The main objective of this study is to evaluate the characteristics combustion that combine premixed charge compression ignition (PCCI)-based with conventional mixing controlled combustion.In type combustion, it supposed duration shortened due synchronization timing two types combustions.In addition, cooling loss caused by spray impingement expected decrease reduction proportion study, effect injection pressure, timing, and split on thermal efficiency emissions were investigated in order...

A reduced kinetic model for the combustion of n-heptane, i-octane, n-cetane and heptamethylnonane was developed based on a prior designed use with primary reference fuel consisting n-heptane i-octane. The present model, which can be easily employed in conjunction conventional computational fluid dynamics code, contains 59 chemical species 96 reactions. Predicted ignition delay times under high pressure temperature conditions were generated using this new compared those obtained from full...