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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Characteristics of carbony compounds from a heavy-duty diesel engine fueled with dimethyl ether-diesel blend

Cheng, Yi-Jie 23 June 2011 (has links)
In this research, used dimethyl ether as second fuel blended with diesel (mixed quantity with 10 L/min to 60 L/min, interval 10L/min), which test behavior of diesel engine and carbonyls emission investigated. The engine operated at steady-state condition of 1600 rpm, 145 Nm torque , eight kinds of carbonyls were sampling and analysis, and discuss the performance of the ozone formation potential (OFP). The results of regulated pollutant emissions, CO, THC and PM emission could increasing with the addition of DME, NOX emissions, along with the mixed rate of per minute from 10 L, 20 L, 30 L, 40 L, 50 L and 60 L of its reduction rate was 6.8%¡B8.3%¡B10.0%¡B10.6%¡B13.1% and 15.4%, shows that the DME can reduce NOX emissions. Add a various amount of dimethyl ether , which carbonyl compounds emission from the gas flow 0 L(with neat diesel), 10 L, 20 L, 30 L, 40 L, 50 L and 60 L concentrations were 2507.44 g/m3, 2665.27 g/m3, 2726.67 g/m3, 2958.07 g/m3, 4645.87 g/m3, 5470.20 g/m3 and 7279.91 g/m3; the emission factor of 143.58 mg/bhp-hr, 152.65 mg/bhp-hr, 156.62 mg/bhp-hr, 168.69 mg/bhp-hr, 266.22 mg/bhp-hr, 312.38 mg/bhp-hr and 416.36 mg/bhp-hr, shows the addition of DME will rising the carbonyl compound emissions of diesel engine. Gas of dimethyl ether (10,20,30,40,50 and 60 L/min) into the neat diesel fuel (0 L/min) as a mixture fuel additives, the effect of ozone formation potential as increase in the total ozone formation potential, 21945.93 g-O3/m3, 23698.40 g-O3/m3, 24427.46 g-O3/m3, 26672.98 g-O3/m3, 42683.69 g-O3/m3, 50519.26 g-O3/m3 and 67710.60 g-O3/m3 respectively, and ozone manufacturability will 0 L/min of 8.75 increased to 60 L/min of 9.30.
32

Saving Energy and Reducing Carbonyl Compounds Emissions using H2/O2 Alternative Fuel on a Heavy-Duty Diesel Engine

Wang, Ying-Lan 23 June 2011 (has links)
This research carries out all tests in diesel engine takes neat diesel and hydrogen+oxygen (H2/O2) which is used as an additive (H2/O2 mixture: 10 to 70 L/min, interval 10 L/min) in a stable state condition (engine was operated at one load steady-state condition of 1600 rpm with torque and power outputs of 145 Nm and 24.5 kW, respectively). Characteristics of carbonyls emissions from H2/O2 as an additive were investigated in a HDDE (heavy-duty diesel engine) and compared with those from neat diesel, contains the concentration, emission factor and elimination efficiency, whole of change tendency in order to help the understanding of diesel engine pollutant emissions, and appraises energy conservation of benefit which add to H2/O2. The regulated pollutants emission, using H2/O2 mixture (10 to 70 L/min), THC, CO, CO2 and PM emission all increased while H2/O2 showed signs of decrease; on the contrary, NOx emission increased while H2/O2 increased. Regarding Carbonyls emissions, the total carbonyls concentration of diesel engine take neat diesel was 3218.02 £gg/m3 and the emission factors for diesel engine take neat diesel were 180.882 mg/bhp-hr and 788.061 mg/L-fuel, respectively. When H2/O2 mixture was added, total carbonyls concentration of 3068.28, 3006.42, 2823.10, 2707.06, 2500.54, 2216.87 and 2178.27 mg/m3 were 10 L/min, 20 L/min, 30 L/min, 40 L/min, 50 L/min, 60 L/min and 70 L/min, respectively. The emission factor may be divided into mg/bhp-hr and mg/L-fuel; the emission factor of total carbonyls were 231.36¡B226.18¡B211.41¡B203.14¡B186.98¡B167.17 and 164.23 mg/bhp-hr, respectively; the emission factor of total carbonyls were 764.95¡B755.15¡B719.97¡B707.36¡B704.40¡B694.27 and 690.47 mg/L-fuel, respectively. Increases in H2/O2 can reduce total carbonyls emissions with an eliminating efficiency rate of 4.7, 6.6, 12.3, 15.9, 22.3, 31.1 and 32.3%, respectively. Energy conservation of appraisal increase H2/O2, diesel equivalent sun of fuel consumption of diesel engine and electricity consumption of H2/O2 generator, namely can distinguish that its energy consumption, whole consumes were 2.51, 2.58, 2.59, 2.57, 2.60, 2.43, 2.26 and 2.25, respectively. When compared with neat diesel, result showed in H2/O2 from 10 L/min to 40 L/min, diesel equivalent increased while H2/O2 showed increase; but in H2/O2 from 50 L/min to 70 L/min reflected in a gradual decrease in diesel equivalent, indicating that increases in H2/O2 can effectively achieve energy conservation. The result showed that energy conservation was 3.4%, 10.0% and 10.6% for 50 L/min, 60 L/min and 70 L/min, respectively. The result indicated H2/O2 was 60 L/min when energy conservation benefit was most remarkable, therefore this had the best energy conservation.
33

Emission Characteristics of Polycyclic Aromatic Hydrocarbons from a Heavy-Duty Diesel Engine mixed with constant H2/O2 and diesel/Biodiesel blends

Wu, Shin-Yi 26 June 2012 (has links)
This study investigated emission characteristics of polycyclic aromatic hydrocarbons (PAHs) and reductions of regulated harmful matters using Premium diesel fuel (PDF), mixed with a 60 L/min flow rate of H2/O2 mixture and blended with biodiesel 5% (B5), 10% (B10), 20% (B20), and 30% (B30). The diesel engine was operated at steady-state condition of 1,600 rpm, with torque and power outputs of 145 Nm and 24.5 kW, respectively. Measured results show that the emission concentrations of total PAHs were 22.42, 20.11, 17.28, 13.45, and 13.13 £gg/m3 for B0, B5, B10, B20, and B30, respectively, with corresponding emission factors of total PAHs being 1334.53, 1198.82, 986.05, 771.93, and 748.82 £gg/bhp-hr, and reductions of total PAHs being 10.3, 22.9, 40.0, and 41.4%. The results indicated that using biodiesel can reduce PAH emissions. However, the emission factors of carbon monoxide (CO) and total hydrocarbons (THC) were decreased by adding biodiesel, but those of carbon dioxides (CO2), nitrogen dioxides (NOx), and particulate matter (PM) were increased. Annual emissions of total PAHs were estimated to be 140.05, 126.92, 105.21, 81.97, and 79.86 ton/year for B0, B5, B10, B20 and B30, respectively, decreasing with increasing biodiesel. Also, the corresponding annual emissions of BaPeq were 5.88, 5.62, 3.50, 3.03, and 2.83 ton/year, respectively.
34

Effects of isobutanol-diesel blend on carbonyl compounds characteristics in a heavy-duty diesel engine

Yang, Hau-Siang 29 June 2012 (has links)
This research conducted exhaust tests in an HDDE (heavy-duty diesel engine) using pure diesel fuel mixed with 10 to 30% isobutanol under the condition of U.S. Transient Cycle. Characteristics of 18 carbonyls emissions were investigated and compared with those using pure diesel. Results showed that the brake power (BP) and brake thermal efficiency (BTE) were decreased with increasing isobutanol mixtures (10 to 30%). Brake specific fuel consumption (BSFC) was increased for isubutanol ¡Ø 10%, but was decreased for isubutanol above 10%. The regulated emissions of CO, PM and NOx were decreased, but CO2 and THC were increased, due to variations of cetane number and heating value. Total carbonyls emission concentrations with pure diesel fuel were 893.25 £gg/m3, with emission factors being 52.57 mg/bhp-hr or 218.44 mg/L-fuel. When 10 to 30% isobutanol mixture was added, total carbonyls concentrations ranged from 1108.21 to 2622.27 £gg/m3, with emission factors being 268.83 to 610.94 mg/L-fuel, or 68.93 to 175.25 mg/bhp-hr. The ozone formation potential of diesel engine with pure diesel fuel was 7132.72 g-O3/m3.When 10 to 30% isobutanol mixture was used, total ozone formation potential ranged from 8764.39 to 20168.73 g-O3/m3. Total carbonyls emissions were increased with increasing isobutanol contents. In summary, addition 10% isobutanol was an optimal blend, since both fuel saving and reductions of pollutant emissions can be achieved.
35

The study of energy saving and pollution reduction by H2/O2 addition to the diesel engine combustion chamber

Cheng, Chia-Yu 07 August 2012 (has links)
Hydrogen is generally acknowledged to have a high heat value and emit few pollutants. It has been identified as the fuel with the most potential for the twenty-first century. This study investigates energy saving and pollutant reduction for polycyclic aromatic hydrocarbons (PAHs), hydrocarbons (HCs), carbon monoxide (CO), carbon dioxide (CO2), particulate matter (PM), and nitrogen oxides and a hydrogen (H2) and oxygen (O2) mixture (H2/O2) mixed in a diesel engine combustion chamber. Experimental parameters included a speed of 1600 rpm and a torque of 145 Nm in the steady-state condition. These operating conditions represent a speed of 40km/hr, roughly vehicle speed in an urban area. In this study, premium diesel fuel (PDF) was mixed with H2/O2 at different injection rates. When mixed with PDF, the H2/O2 injection rate was set to 60L/min, while different biodiesel injection rates were used in the diesel engine combustion chamber. In addition, this study used mathematical simulation to model the combustion temperature, combustion efficiency, and combustion gas distribution in the combustion chamber. The results of PDF mixed under different H2/O2 injection rates showed that the brake thermal efficiency (BTE) did not significantly change when the H2/O2 injection rate rose from 0 L/min to 40L/min, but markedly increased when the H2/O2 injection rate increased from 50 L/min to 70L/min. The best BTE of the diesel engine was 35.4% at an H2/O2 injection rate of 60 L/min, roughly 12.6% higher than PDF. The brake specific fuel consumption (BSFC) was 16.287 g/bhp-hr at an H2/O2 injection rate of 60 L/min, 11.72% lower than PDF. The results of the BTE and BSFC showed that an H2/O2 injection rate of 60 L/min enabled the best performance of the diesel engine. Emissions of CO, CO2, THC, PM, and PAHs fell as the H2/O2 injection rate increased, while the NOx emission increased as the H2/O2 injection rate increased. This was because the addition of H2/O2 improved the combustion efficiency of the fuel. The total oil equivalent saving was about 22.13% compared to neat diesel at an H2/O2 injection rate of 70 L/min. The BTE decreased from 37.0% to 35.5% while the BSFC increased to 149.75 g/bhp-hr when the PDF was mixed with biodiesel and the injection rate of H2/O2 was set at 60 L/min. These results showed that the performance of the diesel engine declined slightly. The BTE of the 30% biodiesel + PDF decreased roughly 1.5% compared to pure PDF. The emissions of CO, THC, and PAHs decreased as the percentage of biodiesel mixed with PDF increased, but CO2, NOx, and PM increased as the proportion of biodiesel rose. In the mathematical simulation, H2/O2 was mixed with combustion air at injection rates of 0, 30, 60, and 70 L/min, using C12H26 as the main fuel. The simulation investigated the combustion flame temperature, fuel combustion efficiency, and combustion gas distribution in the diesel engine combustion chamber. The results showed that the combustion temperature and combustion efficiency improved as the H2/O2 injection rate increased.
36

Electrifying the construction process : Replacing diesel engines with electric motors

Willerström, Jakob, Linde, Adam, Fagrell, Johannes January 2015 (has links)
Diesel engines are commonly used in construction machines, for example excavators. In a diesel engine, the combustion of diesel is a process with a considerable environmental impact, with high amounts of emitted greenhouse gases. The bachelor thesis creates a model that investigates the potential of decreasing the environmental impact when replacing diesel engines with electric motors in the construction phase of the construction process of buildings. The model was made in three steps. In the first step the electric motors’ energy consumption were compared with the diesel engines’ energy consumption. Secondly, the results of the comparison were contrasted against the results of an implemented example as to determine the relevancy of the model. Finally, the carbon dioxide equivalent values of the diesel engines and the electric motors were calculated and compared. The result shows that there is a big potential of decreasing the environmental impact. The reduction is in the order of 63%-99% and it is shown that the share of renewable energy sources in the electricity mix is vital as to make the potential as large as possible.
37

カーボン粒子を用いたDPFの捕集及び再生性能の評価

YAMAMOTO, Kazuhiro, SUZUKI, Kazuya, 山本, 和弘, 鈴木, 一也 07 1900 (has links)
No description available.
38

LII 法によるすす計測とディーゼル排気ガスへの適用

GAKEI, Shigefusa, YAMASHITA, Hiroshi, HAYASHI, Naoki, TAYA, Yukihiro, FUJIKAKE, Fumihiro, YAMAMOTO, Kazuhiro, 可計, 重英, 山下, 博史, 林, 直樹, 田谷, 幸洋, 藤掛, 文裕, 山本, 和弘 January 2008 (has links)
No description available.
39

DPF内のすす堆積を考慮した流れの数値解析

DAIDOU, Shigeki, YAMASHITA, Hiroshi, YAMAMOTO, Kazuhiro, OHORI, Shinya, 大道, 重樹, 山下, 博史, 山本, 和弘, 大堀, 晋也 January 2009 (has links)
No description available.
40

連続再生式ディーゼルフィルターにおけるすすの燃焼と堆積の数値解析

YAMAMOTO, Kazuhiro, MATSUI, Kenta, 山本, 和弘, 松井, 健太 January 2010 (has links)
No description available.

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