• 한국자동차공학회논문집
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• 제18권6호
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• pp.105-113
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• 2010

In this study, a feasibility test of liquid petroleum gas (LPG) compression ignition (CI) engine has been carried out to study the effectiveness of cetane enhancing additive: Di-tertiary-butyl peroxide (DTBP). Performance and emissions characteristics of a CI engine fuelled with DTBP blended LPG fuel were examined. Also, the effect of EGR (exhaust gas recirculation) on the combustion and emissions characteristics has been investigated. Results showed that stable engine operation over a wide range of the engine loads was possible. Exhaust emissions measurements showed that hydrocarbon were decreased with the blended fuel at enhancing cetane number. Furthermore, the combustion stability of LPG with a cetane number improver was equivalent to that of commercial Diesel fuel. Increasing the EGR rate leads to deteriorate the IMEP (indicated mean effective pressure) and increase the ignition delay. It was found that the exhaust emissions with the EGR resulted in a very large reduction in nitrogen oxides at the expense of higher THC and CO emissions. Considering the results of engine performance and exhaust emissions, LPG blended fuel of enhancing cetane number could be used as an alternative fuel for diesel in a CI engine.

• International Journal of Automotive Technology
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• 제8권1호
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• pp.1-7
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• 2007

The effect of the di-tertiary butyl peroxide (DTBP) additive on the heat release rate and emissions of a homogeneous charge compression ignition (HCCI) engine fueled with high Research Octane Number (RON) fuels were investigated. The experiments were performed using 0%, 1%, 2%, 3%, and 4% (by volume) DTBP-RON90 blends. The RON90 Fuel was obtained by blending 90% iso-octane with 10% n-heptane. The experimental results show that the operation range was remarkably expanded to lower temperature and lower engine load with the DTBP additive in RON90 fuel. The first ignition phase of HCCI combustion was observed at 850 K and ended at 950 K while the hot ignition occurred at 1125 K for all fuels at different engine working conditions. The chemical reaction scale time decreases with the DTBP addition. As a result, the ignition timing advances, the combustion duration shortens, and heat release rates were increased at overall engine loads. Meanwhile, the unburned hydrocarbon (UHC) and CO emissions decrease sharply with the DTBP addition while the NOx emissions maintain at a lower level.

• 폴리머
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• 제31권4호
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• pp.343-348
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• 2007

이 논문에서는 vinylidene fluoride(VDF), trifluoroethylene(TrFE), chlorotrifluoroethylene(CTFE)을 사용하여 3성분계 고분자를 합성하였으며, 저온 개시제 di-tertiary-butylperoxide(DTBP)를 사용하여 현탁중합하였다. NMR, FT-IR을 통해 3성분계 고분자 사슬의 미세구조, 사슬형태의 변화에 대해 알 수 있었다. CTFE mol%가 증가할수록 $\beta$ 상태는 점차적으로 감소하고 $\gamma$ 상태는 증가하는 것을 알 수 있었다. DSC 분석결과, CTFE mol%가 증가할수록 상전이 온도($T_c$)는 상온으로 낮아지며 그 곡선은 점차 작아지고 넓게 퍼지는 현상을 확인하였다. 활성화 에너지는 Freeman-Carroll법에 의해 계산되었다.