Karin, Preechar

Preferred name

Karin, Preechar

Alternative Name

Karin, P.

Karin, Preecha

Main Affiliation

School of Engineering

preechar.ka@kmitl.ac.th

Now showing 1 - 10 of 28

Some of the metrics are blocked by your
consent settings
Effects of variable O2 concentrations and injection pressures on the combustion and emissions characteristics of the petro-diesel and hydrotreated vegetable oil-based fuels under the simulated diesel engine condition
(2018-12-01)
Vo, C.
;
Charoenphonphanich, C.
;
Karin, P.
;
Susumu, S.
;
Hidenori, K.
This experimental research investigates the effects of variable O<inf>2</inf> concentrations and injection pressures on the combustion and emissions characteristics of the diesel (B7) and the hydrotreated vegetable oil (HVO)-based fuels. The O<inf>2</inf> concentrations included 21%, 15% and 10% O<inf>2</inf>, while the injection pressures were 80 and 120 MPa. The experimental fuels were the diesel fuel (B7), the neat HVO, the 20%, 50% and 80% HVO (by mass fraction) blended with the diesel. The experiments were carried out in a rapid compression-expansion machine (RCEM) under the direct injection (DI) diesel combustion condition. The analysis was undertaken using the two-color method. The experimental results indicated that the ignition delay, the heat release rate, the flame temperature, the soot density-KL factor, the NO<inf>x</inf> and soot-out emissions were inversely correlated to the HVO fraction in the blend. In addition, the findings revealed the similar flame profiles in which the higher flame temperature region and the darker KL density were concentrated around the spray flame upstream, regardless of the HVO mixing ratio. Besides, the decrease in the O<inf>2</inf> concentration resulted in the lower heat release rate, integral heat release, flame temperature, KL factor and NO<inf>x</inf> emissions but the longer ignition delay and higher soot concentration, with the highest soot concentration observed under the 15% O<inf>2</inf> environment. Nevertheless, the higher pressure differential (i.e. between the injection pressure and the ambient pressure) contributed to the shorter ignition delay, higher heat release rate, early peak of the flame temperature, wider combustion area, faster soot oxidation rate and higher NO<inf>x</inf> production.
Some of the metrics are blocked by your
consent settings
Injection Characteristics of Palm Methyl Ester Blended with Diesel Using Zuech’s Chamber
(2018-06-01)
Srichai, Prathan
;
Ewphun, Pop Paul
;
Charoenphonphanich, Chinda
;
Karin, Preechar
;
Tongroon, Manida
This research attempts to characterize the injection of palm biodiesel blended with diesel in a Zuech’s chamber. Thailand conventional diesel (mandated blend of biodiesel at 5 % or B5), palm biodiesel (B100) and four other biodiesel blends ratios (B20, B40, B60 and B80) were investigated with single hole injector of 140 and 200 μm diameters, injection pressure of 40 MPa to 160 MPa, constant back pressure of 4.5 MPa and energize time of 2.5 ms. The results show that increasing biodiesel blending ratios leads to longer injection delay, larger injection pressure drop, smaller injection quantity discharge coefficient (C<inf>d</inf>) and shorter injection duration. With increasing biodiesel blending ratio, high Cavitation number from biodiesel viscosity decreases Reynolds number. Increasing injector diameter from 140 μm to 200 μm has reduced injection delay, increased fuel injection quantity, discharge coefficient and remaining injection duration. The increasing of injection pressure were improve, injection delay, injection duration, injection quantity and discharge coefficient until injection pressure 120 MPa. In addition at injection pressure over 120 MPa are decrease injection quantity and discharge coefficient, it effect form the cavitation phenomena. Increasing of viscosity, density, Bulk modulus and sound velocity were effect to increase injection delay, with reduce injection quantity, injection duration and pressure drop during injection process.
Some of the metrics are blocked by your
consent settings
Comparison study on fuel properties of biodiesel from jatropha, palm and petroleum based diesel fuel
(2014-01-01)
Borhanipour, Morteza
;
Karin, Preechar
;
Tongroon, Manida
;
Chollacoop, Nuwong
;
Hanamura, Katsunori
The increase of air pollution and global warming is a threat for human life. Besides, the price of petroleum is increasing rapidly and the resources are diminishing. This obliged scientists and engineers to look for alternative sources of energy, which are cleaner and more sustainable. Biodiesel, defined as mono-alkyls of esters from vegetable oils and animals fat, is a cleaner renewable fuel and has been considered as the best alternative for petroleum based diesel fuel hence it can be used in any compression ignition engines without any significant modification. The main advantages of using biodiesel are its renewability and better quality of exhaust gas emissions due to their higher content of oxygen. The produce less soot and hence the feed stuck is plant it will regenerate the CO2 by the photosynthesis which ensures the renewability and reduces global warming. But these alternative fuels have faced some obstacles while utilizing in CI engines which are due to some of their physical and chemical characteristics. At this study the fuel properties of jatropha biodiesel and its blends (a non-edible feedstock) were compared with the properties of Palm biodiesel (an edible feedstock) and petroleum based diesel. The viscosity, density, oxidation stability, acid value, water content, iodine value, flash point, pour point, cloud point and calorific value of the samples were analyzed an discussed. The physical properties of the biodiesels are controlled by their chemical properties such as unsaturation level of fatty acids and oxidation stability. Results show that the viscosity of jatropha is higher than palm biodiesel although the density of palm biodiesel is higher. Oxidation stability of the biodiesel has impact on several chemical and physical properties and improvement of oxidation stability can make betterment in these properties. The results of this study will be used as a data backup for another research project. Copyright © 2014 SAE International and Copyright © 2014 TSAE.
Some of the metrics are blocked by your
consent settings
Characterization of carbon fiber and glass fiber's micro and nanostructure using electron microscopy, raman spectroscopy and xrd analysis
(2019-03-25)
Man, Tial Cuai
;
Karin, Preechar
;
Ohtake, Naoto
;
Aakasaka, Hiroki
;
Larpsuriyakul, Patcharee
Nowadays, most manufacturers are looking for the improvement of lightweight parts and other components in the automobile field. Carbon fiber and glass fiber are the most effective materials for their requirement to reduce the weight in vehicles due to their light weight and high tensile strength. The diameter of carbon fiber is 6 μm while glass fiber diameter is 17 μm. The mechanical tensile force of carbon fiber and glass fiber are 430 N and 290 N respectively on fiber alone without matrix. Carbon fibers are gradually smaller in each filament due to tensile force. Approximately 5 mm are elongated for both carbon fiber and glass fiber in tensile test report. In current research, characteristic and tensile force of carbon fiber and glass fiber were investigated by using electron microscopy, Raman spectroscopy and XRD.
Some of the metrics are blocked by your
consent settings
Effect of biofuel and soot on metal wear characteristic using electron microscopy and 3D image processing
(2017-11-05)
Karin, Preechar
;
Amornprapa, Warawut
;
Khamsrisuk, Phiranat
;
Budsayahem, Pol ake
;
Chammana, Pattara
The soot contamination in used engine oils of diesel engine vehicles was about 1% by weight. The soot and metal wear particle sizes might be in the range of 0-1 µm and 1-25 µm, respectively. The characteristics of soot affecting on metal wear was investigated. Soot particle contamination in diesel engine oil was simulated using carbon black. Micro-nanostructure of soot particles were studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and laser diffraction spectroscopy (LDS). The metal wear behavior was studied by means of a Four-Ball tribology test with wear measured. Wear roughness in micro-scale was investigated by high resolution optical microscopy (OM), 3D rendering optical technique and SEM image processing method. It was found that the ball wear scar diameter increased proportionally to the soot primary particle size. The effect of biodiesel contamination were also increasing in wear scar diameter.
Some of the metrics are blocked by your
consent settings
Impact of Engine Oil Additives on Nanostructure and Oxidation Kinetics of Diesel and Synthetic Biodiesel Particulate Matters using Electron Microscopy
(2019-12-19)
Koko, Phyozin
;
Karin, Preechar
;
Charoenphonphanich, Chinda
;
Chollacoop, Nuwong
;
Hanamura, Katsunori
Physicochemical characteristics of particulate matters which are influenced by engine oil additives from engine combustion of diesel and synthetic biodiesel: Hydrotreated vegetable oil (HVO) were successfully investigated using electron microscopy, electron dispersive X-ray spectroscopy and thermogravimetric analysis. The agglomerate structure of diesel PM, HVO PM and diesel blending lubricant PM are similar in micro-scales. However, nanostructure of soot is a spherical shape composed of curve line crystallites while the metal oxide ash nanostructure is composed of parallel straight line hatch patterns. The oxidation kinetics of fuel blending lubricant PMs are higher than neat fuel PMs due to catalytic effect of incombustible metal additives from engine lubricating oil.
Some of the metrics are blocked by your
consent settings
Physical characterization of biodiesel particle emission by electron microscopy
(2013-01-01)
Karin, Preechar
;
Songsaengchan, Yutthana
;
Laosuwan, Songtam
;
Charoenphonphanich, Chinda
;
Chollacoop, Nuwong
Nanostructures of diesel and biodiesel engine particulate matters (PMs) were investigated by using a Transmission Electron Microscopy (TEM). The average single particle sizes of biodiesel and diesel PMs are approximately 30-40 nm and 50-60 nm, respectively. Image processing process was used to estimate each carbon platelet length by using TEM image. The average carbon platelet length of biodiesel and diesel PMs are in the range of 0.1-7.0 nm. Moreover, carbon atoms per cubic volume of PMs are approximately 500-900. The result shows that engine load and fuel property are strongly impact on the size of single particle and carbon atom density of particle. This is one of interesting behaviors need to be investigated for better understanding. The results of this research would be used as basic information for design and develop removing process of PM emitted from engine combustion which using in diesel and biodiesel fuels. © Copyright @2013 SAE Japan and Copyright @ 2013 SAE International.
Some of the metrics are blocked by your
consent settings
Impact of engine oil's additives on particulate matter's micro-and nanostructure using electron microscopy image analysis
(2019-01-01)
Koko, Phyozin
;
Karin, Preechar
;
Rungsritanapaisan, Sippakorn
;
Tongsri, Ruangdaj
;
Hanamura, Katsunori
According to increasingly stringent emission regulations on particle emissions from automotive vehicles, a diesel engine must be equipped with diesel particulate filter (DPF) to trap the particulate matters (PMs) which can be harmful to human health. Morphology and chemical composition of particulate matters were successfully studied using electron microscopy and electron dispersive x-ray spectroscopy (EDS) analysis. Microstructure of particulate matters derived from diesel blending lubricating oil were not significant different compared to diesel PM. Nanostructure of soot is a spherical shape composed of curve line crystallites and the particle sizes were in the range of 10 -60 nm while the metal oxide ash is composed of lattice fringes. Chemical composition analysis of EDS result showed that metallic additives from lubricating oil cannot be burned during combustion and might be transformed into metal oxide ash.
Some of the metrics are blocked by your
consent settings
Battery sizing for electric vehicles based on real driving pattern in Thailand
(2018-01-01)
Duangsrikaew, B.
;
Mongkoltanatas, J.
;
Karin, P.
;
Hanamura, K.
;
Benyajati, C.
The purpose of this study was to carry out a battery sizing based on the fulfilment of power requirement from the representative real driving pattern in Thailand. The real driving cycle data i.e. velocity and vehicle global position were collected through a GPS-based equipment, VBOX. The driving data transportation services provided in a campus of university based in the rural area of Bangkok were collected from three different types of i.e. closed-area, inter-city and local feed. Three campus driving data types were gathered to achieve a suitable dimensioning of battery systems for electrified university public buses.
Some of the metrics are blocked by your
consent settings
Spray visualization of biodiesel and diesel in a high pressure chamber
(2014-01-01)
Srichai, Prathan
;
Chareonphonphanich, Chinda
;
Karin, Preechar
;
Chollacoop, Nuwong
The present research attempted to characterize fuel spray pattern, such as spray angle, spray penetration and their mixture formation by recourse to images analysis. Diesel and biodiesel were used to investigate via a single hole injector (solinoild type) in a constant volume high-pressure chamber. In this experimental study, the spray characteristics of diesel and biodiesel fuel were comparatively evaluated. Initial conditions were ambient temperature, ambient density of 21 kg/m<sup>3</sup>, injection durations varied from 0.5 and 1 ms and rail pressure of 400 and 800 bar. The series of images were captured by high speed video camera with resolution of 7,500 frames per second and shutter speed of 1/10,000 sec under Schlieren photography technique. The result showed the biodiesel spray penetration was longer than that of the diesel, and spray angle of biodiesel in start injection was larger than biodiesel. From the results, it can be concluded that the higher the density and viscosity of biodiesel, the stronger the effect on the spray mixture formation. © (2014) Trans Tech Publications, Switzerland.

Karin, Preechar

Filters

Settings

Sort By

Results per page