液化石油氣輔助燃料之柴油引擎係使用引擎高溫缸套水供應液化石油氣的汽化熱，但是引擎冷車啟動與暖車期間，引擎本體均未達到工作溫度，以致缸套水熱量不足以供應液化石油氣蒸發，故需在引擎運轉一段時間之後才能使用液化石油氣。如果引擎啟動後太早使用液化石油氣，將使液化石油氣液氣混合物與空氣無法充分混合，導致引擎燃燒不完全影響引擎運轉性能。
本研究係使用預先加熱系統安裝於液化石油氣為輔助燃料之柴油引擎的燃料供應系統上，在引擎啟動前，蒸發器內的液化石油氣尚未足夠熱度缸套水可以蒸發時，預先對於液化石油氣進行加熱。本文將引擎運轉分為兩個部分，第一係加熱器於未加熱或加熱加熱器溫度維持在60℃，探討液化石油氣對於柴油引擎冷啟動過程的運轉性能分析；第二為柴油引擎於怠速運轉同時對液化石油氣進行加熱蒸發至30℃並維持一定，同時量取汽缸內壓力數據與排氣污染物，進行污染排放、燃燒分析及加熱模式比較，進而探討液化石油氣為輔助燃料之柴油引擎冷啟動或及速運轉性能與各污染物的生成機制。
結果發現，在柴油引擎冷啟動過程或怠速運轉期間，利用加熱器加熱液化石油氣可使引擎在冷啟動運轉後約六十秒左右就可達到穩定運轉，可得到缸內燃燒狀況良好、燃燒循環變異低、較低的污染值。但發現當混合比例高於40%且愈高時，則有相反的燃燒效果產生。利用加熱器與蒸發器一同加熱液化石油氣可得最短的加熱時間，單純使用蒸發器加熱其加熱時間最長；利用加熱器與蒸發器引擎則有較長的運轉時間，造成柴油引擎溫度較高，汙染值有較佳的排放表現。所以本實驗利用額外的加熱模式改善液化石油氣為輔助燃料之柴油引擎於冷啟動過程的性能研究是為可行的方式。

The diesel engine using LPG as an auxiliary fuel employs high temperature of cylinder liner water to supply the heat of vaporization of LPG. However, during the period of engine cold-start and warm-up, the engine body does not reach the working temperature, so that the temperature of cylinder liner water is not high enough for LPG to vaporize. Therefore, the engine may use LPG just after it works for a period of time. The LPG liquid and vapor mixture will not mix with air completely if the engine uses LPG too early after starting. As a result, the fuel will burn incompletely in the engine and affect the performance of operation.
In this study, pre-heating system was installed in the liquefied petroleum gas as an auxiliary fuel in diesel engine fuel supply system. Before starting the engine, when the water of evaporate the cylinder does not have sufficient heat to evaporate the liquefied petroleum gas, it can advance for liquefied petroleum gas for heating. This study will be divided into two parts of engine operating; in the first part, the heater is not or heating with the heating temperature is maintained at 60℃, and investigate the operating performance of liquefied petroleum gas for diesel engine during cold start. In the second part, when the diesel engine runs in idle period, constant liquefied petroleum gas is heated and vaporizes to 30 ℃ and maintained. In addition, the cylinder pressure data and exhaust pollutants were measured for pollution emissions, combustion analysis, and heating mode comparison, and this study then explores the liquefied petroleum gas as auxiliary fuel or diesel engine cold start and idle performance and speed the formation mechanism of various emissions.
From the results, during the diesel engine cold start process or idle period, use heater of heating liquefied petroleum gas can reach stable operation of the engine during cold start operation of about 60 seconds
, and obtain the good combustion condition of cylinder, low combustion cycle variation , and lower emissions. However, when the mixing ratio is higher than 40% and more, and then there is the opposite of combustion generated. Using heater and evaporator heating liquefied petroleum gas has the shortest heating time, and simply using the evaporator heating the heat has longest time. Use of heater and evaporator has a longer engine running hours, causing the temperature of diesel engine higher, and then emissions performance have better value. Therefore, this study using additional heating mode to improve the liquefied petroleum gas as auxiliary fuel for diesel engines during cold-start performance of the process is feasible way.

[1]John B. Heywood著，蘇金佳譯，”內燃機”，美商麥格羅．希爾國際股份有限公司出版，pp.4-6，pp. 645-717。
[2]S. Onishi, S. Hong JO, “Active Themo Atmosphere Combustion(ATAC) - A New Combustion Process for Internal
Combustion Engines”, SAE 790501,1979.
[3]M. Christensen, A. Hultqvist, “Demonstrating the Multi Fuel Capability of a Homogeneous Charge Compression Ignition Engine with Variable Compression Ratio”. SAE 1999-01-3679,1999.
[4]M. Christensen, “Influence of Mixture Quality on Homogeneous Charge Compression Ignition ”. SAE982454,1998.
[5]Hisakazu Suzuki, “Combustion Control Method of Homogeneous
Charge Diesel Engines”, SAE980509,1998.
[6]楊成宗，趙志勇，”液化石油汽車- LPG引擎”，全華出版81.7。
[7]國立成功大學機械所梁燕輝教授，”天然氣當作柴油燃料的評價”
，國科會專題研究，1990年11月。
[8]Namiki, Tsukuba, ”LPG-Diesel engine “ Int. J. of Vehicle Design，Vol.15，NO 3/4/5,1994 pp. 279-290.
[9]A.K. Shahad Haroun, K. A. Mohammed Yassar, “Investigation of soot formation and temperature field in laminar diffusion flames of LPG-air mixture”, Energy Conversion & Management 41(2000) pp.1897-1916.
[10]邵千鈞，何文華，周文華，”LPG進氣道液態噴射的實驗研究”
內燃機學報Vol.21(2003)No.1, pp. 65-68.
[11]C. V. Sudhir, Desai Vijay, ”Studies on influence of injection timing
And diesel replacement on LPG-Diesel dual duel engine”, 2003 Fall Technical Conference of the ASME internal Combustion Engine Division , pp. 161-166.
[12]QI Dong-hui, Bian Yao-zhang, ”Engine Operation on LPG / Diesel
Mixing Fuel in DI Diesel Engine” Transaction of CSICE Vol.21(2003) No.6 pp. 428-434.
[13]鄭博鴻，”均質進氣壓縮點火引擎之研究”，碩士論文，國立海
洋大學輪機所，中華民國93年6月。
[14]吳鴻文，”漁船用柴油機已液化石油氣為輔助燃料之性能”，行
政院農委會漁業署研究報告，2005年12月。
[15]Rong Fang Horng , “Effect of input energy on the emission of a
motorcycle engine　with an electrically heated catalyst　in cold-
start conditions”, Applied Thermal Engineering 24, 2004, pp.2017-2028.
[16]王振鎖，肖宗成，王惠萍，”LPG電控噴射冷起動迴圈的著火
及HC排放影響因素分析”，汽車工程，(2004)Vol.26，No.2，pp.
157-161.
[17]高國珍，陳光敏，王育輝，”柴油機燃用液化石油氣的試驗研
究”，南昌大學學報，工科版，2006年6月。
[18]Liu Zhimin a, Li Liguang b, Deng Baoqing c¸”Cold start character-
istics at low temperatures based on the first firing cycle in an LPG
engine”, Energy Conversion and Management 48 (2007) 395-404.
[19]Yeom Kitae, Jang Jinyoung, Bae Choongsik ,” Homogeneous
charge compression ignition of LPG and gasoline using variable
valve timing in an engine”, Fuel 86 (2007) 494-503.
[20]J Cao, Y Bian, D Qi, Q Cheng and T Wu, “Comparative
investigation of diesel and mixed liquefied petroleum gas/diesel
injection engines”, Proc. Instn Mech. Engrs Vol. 218 Part D: J.
Automobile Engineering , D10803 IMechE 2004.
[21]M. Ghazikhani, M. R. Kalateh, Y. K. Toroghi, Y. K. Toroghi, “An
Experimental Study on the Effect of EGR and Engine Speed on
CO and HC Emissions of Dual Fuel HCCI Engine”,
PROCEEDINGS OF WORLD ACADEMY OF SCIENCE
,ENGINEERING AND TECHNOLOGY VOLUME 40 APRIL
2009 ISSN: 2070-3740.
[22]祁東輝，張春化，邊耀璋，”液化石油氣/柴油雙燃料發動機放熱
規律分析”，長安大學，汽車工程，2001年第六期。
[23]栗工，李理光，邱冬平，劉志敏，”冷啟動首循環瞬態HC排放
特性試驗研究”，上海交通大學內燃機研究所，內燃機學報第25卷第2期，2007。
[24]陳漢玉，袁銀南，陳篤紅，張春豐，”LPG/柴油雙燃料發動煙度
排放的試驗研究”，江蘇大學 汽車與交通工程學院，拖拉機與農用運輸車，第34卷第2期，2007年04月。
[25]蘇金佳，” 液化石油氣引擎性能與排氣改善研究”， 國立臺灣大
學機械工程學系暨研究所研究計畫，1996-08。
[26]H.E. Saleh, ” Effect of variation in LPG composition on emissions
and performance in a dual fuel diesel engine”, Fuel 87 (2008)3031–3039.
[27]M. Kramer, L. J. Bintz, T. A. Tappenden, 1973, “Light Duty
Fleet 27. Experience with LP-Gas”, LP-Gas Engine Fuels, ASTM STP 525, p.92~p.111.
[28]Magnus Christensen and Bengt Johnasson, “Influence of Mixture
Quality on Homogeneous Charge Compression Ignition”, 1998 SAE.
[29]Ando Taichi, Isobe Yusuke, Sunohara Daisuke, Daisho Yasuhiro, Jin
Kusaka, “Homogeneous charge compression ignition and
combustion characteristics of natural gas mixtures: the visualization and analysis of combustion”, JSAE 20034005.
[30]Kalton C. Lahue, Ahlstrand, Alan. Richard K.Dupuy,”Fuel Systems and
Emission Control”, by Chek-Chart Publications,third edition, 1994.
[31]V. K. Duggal , “重型替代燃料引擎之現況與發展”，Cummins
Engine Company, Inc., 1996.
[32]R. Greg Pucher and P. David Gardiner, “Alternative Combustion
System Involving Homogeneous Charge Compression Ignition Concept – A Review of Studies Using Methanol, Gasoline and Diesel Fuel”,SAE962063.
[33]Wu Horng-Wen and Sy Jiunn-Der, “Heat Release Analysis in an
Indirect Injection Diesel Engine with Coupled Fuel Injection
/Combustion Model” , Journal of Society of Naval Architects and Marine Engineers, R.O.C, Vol. 16, No.2, pp.39-51, 1997.
[34]N.A. Henein, , and J. A. Bolt, , “Ignition delay in diesel engines”,
Presented at SAE Engineering Congress Detroit, pp 670007.
[35]R. M. Olree and D. L. Lenane, “Diesel combustion cetane number
effects”, SAE 840108,1984.
[36]D. Anderton and P. E. Waters, “Effect of fuel composition on
diesel engine noise and performance”, SAE 820235, 1982.
[37]Svend Henningsen, “Hydrocarbon emissions from the Ignition-
Delay Period in a Direct-Ignition diesel engine”, SAE 841381
,1984.
[38]T. Murayama, T. Yamada, , N. Miyamoto, , and T. Chikashisa, ,
“Nature and reduction of cycle-to-cycle combustion variation in an IDI diesel engine with ethanol-diesel fuel blends”, SAE 831352,1983.
[39]N. Watson, “Turbochargers for the 1980s-Current Trends and
Future Prospects ” , SAE paper 790063, SAE Trans, vol. 88, 1979.
[40]Dae Sik. Kim, Myung Yoon Kim, Chang Sik Lee, “Effect of
premixed gasoline fuel on the combustion characteristics of compression ignition engine” Energy and Fuels, v 18, n 4,p1213-1219, July/August, 2004.
[41]S. Simescu, T. W. Ryan, G.D. Neely, A. C. Matheaus, B. Surampudi
, SAE Tech., 2002-01-0964, Ser. 2002.
[42]Lyn W.T., Calculations of the Effect of Rate of Heat Release on the
shape of Cylinder-pressure Diagram and Cycle Efficiency, Proc. IME(A.D.) 1.34. 1960-1961.
[43]NATIONAL INSTRUMENTS，“挑選你的 LabView Real-Time
佈署平台”，2003 。
[44]National Instrument， “LabView User Manual”， 1996 。
[45]R. House， “Choosing the Right Software for Data Acquisition”，
IEEE Spectrum， Vol. 32 5， May 1995， pp. 24-26， 28-31， 34-39 。
[46]謝勝治、陳璋琪，“ LabView.謝勝治， 陳璋琪編著應用篇 (含
自動量測.遠端監控) ”， 全華科技，民國91年。
[47]蕭子健，王智昱，儲昭偉，“虛擬儀控程式設計，LabView 7X”，高立圖書有限公司，中華民國93年2月。