2.2L四缸汽油引擎各項效率量測與分析

Investigation and Analysis of Engine Efficiency for 2.2L Four Strokes Gasoline Engine

鄒永靖(Yung-Jing Zou)

指導教授 ： 吳浴沂

國立臺北科技大學/機電學院/車輛工程系所/碩士(2014年)

https://doi.org/10.6841/NTUT.2014.00828

摘要

近年來的能源問題與溫室效應是國際重大議題，而引擎的節能技術日新月異，為了有效降低燃油消耗率與提升引擎效率。本研究蒐集國內外文獻，建立各效率的標竿。針對2.2 L 汽油引擎進行實驗，計算出實驗引擎熱效率、機械效率、容積效率和燃燒效率，將與標竿比較分析出實驗引擎的優劣。
本研究首先進行進排氣道流量係數測試，發現進排氣道流量低於標竿，此將造成流動阻力較大。進行原廠引擎實驗，計算各項效率，實驗引擎FMEP (Friction Mean Effective Pressure)數據高於FMEP國際標竿平均曲線，代表摩擦損失高於一般引擎水準。而制動熱效率數據與國際標竿數據比較，其熱效率在水準內，代表該引擎的熱效率不差。燃燒效率在中低負載時高達95%，但高負載時降低到70%，此乃因空燃比過濃。
由燃燒分析數據，各負載Pmax發生角度為6~40 o，不太合理。藉由熱釋放率分析發現，低負載時熱釋放率明顯地過於提前，甚至在壓縮上死點前已燒完50%燃料，造成上死點前浪費太多功去推動活塞。而高負載時熱釋放率明顯地過於延後，不利於對外作功。所以，該引擎體質不差，若能重新設計進排氣道以提升流量係數，以及修正點火角度，將可大幅改善引擎扭力與熱效率。

關鍵字

熱效率 ； 機械效率 ； 容積效率 ； 燃燒效率 ； 燃燒分析

並列摘要

In recent years, energy shortage and greenhouse effect are major issues in the world, and the technology of energy-saving engine are advancing, in order to study and reduce fuel consumption, and improve each efficiency of the engine. The first step is survey paper to build the each benchmark of efficiency. Experiment the target engine and calculate the flow coefficient, thermal efficiency, mechanical efficiency, volumetric efficiency and combustion efficiency. Final to comparative the data of target engine with benchmark, and find out the advantage and disadvantage of the target engine.
This research firstly executes flow coefficient test of intake and exhaust manifold. From the results, the flows of intake and exhaust manifold are lower than the benchmark, that causes poor volumetric efficiency. The target engine has been experimented, and then engine efficiencies are calculated from the experiment results. FMEP (Friction Mean Effective Pressure) of target engine is higher than international benchmark average, representing friction loss higher than normal standard. By comparison of brake thermal efficiency performance, target engine has caught the international benchmark standard. Combustion efficiency is higher than 95% at middle and low load, but decrease to 70% at high load caused by high concentration air-fuel ratio. From combustion analysis results, Pmax occurs 6~40 degrees at each load, seems invalid. By the heat release rate analysis, the heat release rate is obviously over advanced at low load. 50% of fuel is consumed before compress top dead center, causing too much work waste to push piston before top dead center. At high load, the heat release rate is obviously over retarded, the work is unease to be done. Therefore, if spark advance could be regulated, the performance of engine torque and thermal efficiency could be improved.

並列關鍵字

Thermal efficiency ； Mechanical efficiency ； Volumetric efficiency ； Combustion efficiency

參考文獻

4. M. Howlett, B. Enzi, G. Falck, W. Schoeffmann, R. Haslinger and M. Brunner, “CO2 Reduction Potential through Improved Mechanical Efficiency of the Internal Combustion Engine: Technology Survey and Cost-Benefit Analysis”, SAE Technical Paper, No. 2013-01-1740, 2013.

5. R. Flierl, and M. Fluting, “A Gasoline Engine Concept for Improved Fuel Economy –The Lean Boost System “, SAE Technical Paper, No. 2000-01-1227, 2000.

6. S. Adachi, K. Horio, Y. Nakamura, K. Nakano and A. Tanke, “ Development of Toyota 1ZZ-FE Engine”, SAE Technical Paper, No.981087, 1998.

7. M. Yamakawa, T. Youso, T. Fujikawa, T. Nishimoto, Y. Wada, K. Sato and H. Yokohata, “Combustion Technology Development for a High Compression Ration SI Engine”, SAE Technical Paper, No. 2011-01-1871, 2011.

8. A. Kobayashi, T. Satou, H. Isaji, S. Takahashi and T. Miyamoto “ Development of New I3 1.2L Supercharged Gasoline Engine”, SAE Technical Paper, No. 2012-01-0415, 2012.