Experimental Investigation on Auto-Ignition Characteristics of Kerosene Spray Flames

Abstract

To facilitate the better use of RP-3 kerosene in compression ignition engines, the auto-ignition behaviors of RP-3 kerosene spray were experimentally investigated in an optical rapid compression machine. Results show that most of the tests have good ignitability and combustion performance. For all the successful ignited cases, the flame kernel was found to be formed before the steep rise of pressure, which explained that image-based ignition delay time is always shorter than the pressure-based ignition delay time. The effects of ambient environment, injection pressure, and injection delay time on the pressure history, ignition intensity, combustion duration, heat release rate, and other parameters were investigated individually. The ambient environment has a strong influence on ignition delay time by accelerating the chemical reactions, whereas the high injection pressure helps the better vaporization of fuel spray. The effect of injection delay time is non-monotonic as the trade-off relation between heat loss and blending of fuel and oxygen. The heat release rate histories under different conditions were compared and analyzed, and the two-stage heat release phenomenon was observed in the negative temperature coefficient region. The ignition intensity region was determined based on the measured ignition delay times of RP-3 kerosene spray, and multiple linear regression correlation was used to study the ignition delay time sensitivity to multi-factors.

Pengaruh Pencampuran Minyak Tanah Dengan Bahan Bakar Minyak Diesel, Biodiesel Dan Lainnya - Review

“…Gambar 6. Propagasi api dengan temperature ambient 824, 682 dan 646 K [23] Pada Gambar 6 dapat dilihat bahwa propagasi api pada minyak tanah akan berbeda di setiap temperature ambientnya. Pada temperature ambient 646 K dan t = 13,2 ms terlihat bahwa kinerja penguapan yang rendah dibandingkan dengan yang lainnya.…”

“…Pada saat Temperatur 646 K terlihat bahwa tidak terjadi propagasi api yang terbentuk dibanding dengan temperature 682 K dan 834 K. Semakin tinggi temperarur ambient maka kinerja penguapan akan lebih baik, api akan lebih terang dan memiliki propagasi api yang lebih cepat. Sehingga temperature ambient akan sangat berpengaruh terhadap propagasi api yang terbentuk di pembakaran [23].…”

“…Gambar 8 merupakan sudut penyemprotan terhadap tekanan pada campuran minyak tanah. Sudut kerucut semprot, didefinisikan sebagai sudut terbesar yang dibentuk oleh dua garis lurus dari nosel ujung ke batas semprotan [23]. Selanjutnya dengan tekanan injeksi yang berbeda yaitu 0,2; 0,5; dan 0,8 MPa akan dianalisa efek droplet dari Sauter Mean Diameter (SMD) [26].…”