Begell House Inc.
Atomization and Sprays
AAS
1044-5110
23
8
2013
AREA VOID FRACTION ASSOCIATED WITH TWIN-FLUID ATOMIZER
663-676
10.1615/AtomizSpr.2013007456
Vayalakkara
Sivadas
Amrita Vishwa Vidhyapeetham University, Coimbatore - 641112, India
K.
Balaji
Amrita Vishwa Vidhyapeetham University, Coimbatore - 641112, India
I. Krishna
Raj
Amrita Vishwa Vidhyapeetham University, Coimbatore - 641112, India
E.
Vignesh
Amrita Vishwa Vidhyapeetham University, Coimbatore - 641112, India
R.
Aravind
Amrita Vishwa Vidhyapeetham University, Coimbatore - 641112, India
sprays
void fraction
breakup length
effective jet diameter
stretching factor
An empirical characterization of the void fraction in the spray region of liquid jets emanating from a twin-fluid atomizer has been carried out. The present study evolves under primary breakup criteria. That is, the respective breakup length extracted from flow visualization techniques are successfully utilized to find a better functional correlation for the area void fraction with longitudinal distance. The resultant function enables extracting the axial location at which complete atomization occurs for the range of conditions tested. To make the analysis more appealing in the practical domain, the concept of effective jet diameter and associated stretching factor at the nozzle exit plane were introduced. Hence, the validity of results will not be limited to the present test conditions.
INJECTION AND SPRAY CHARACTERISTICS OF BLENDS OF DIESEL FROM DIRECT COAL LIQUEFACTION AND PETRODIESEL
677-695
10.1615/AtomizSpr.2013007690
Jinlong
Bai
Key Laboratory for Power Machinery and Engineering of Ministry of Education, Shanghai Jiao Tong University, Shanghai, 200240, China
Xinqi
Qiao
Key Laboratory of Power Machinery and Engineering, Ministry of Education, Shanghai Jiao Tong University, No. 800, Dongchuan Road, Minhang District, 200240 Shanghai, People's Republic of China
Zhen
Wang
Key Laboratory for Power Machinery and Engineering of Ministry of Education, Shanghai Jiao Tong University, Shanghai, 200240, China
Jian
Zhuang
Key Laboratory for Power Machinery and Engineering of Ministry of Education, Shanghai Jiao Tong University, Shanghai, 200240, China
Zhen
Huang
Key Laboratory of Power Machinery and Engineering, Ministry of Education, Shanghai Jiao Tong University, No. 800, Dongchuan Road, Minhang District, 200240 Shanghai, People's Republic of China
diesel from direct coal liquefaction
injection
spray
petrodiesel
As a new commercial fuel, diesel from direct coal liquefaction (DDCL) has different physical and chemical properties from petrodiesel. The injection and spray characteristics of DDCL petrodiesel and their blends are investigated with a common rail system using EFS method and high-speed photography, respectively. The results show that DDCL proportion hardly influences start of injection but has significantly influences on the end of injection especially in the case of wide injection pulse width. The injection duration lengthens with DDCL proportion and the rise of setting rail pressure inhibits the lengthening. Maximum injection rate increases linearly and rapidly with setting rail pressure, and also increases with injection pulse width, first rapidly then slowly, but does not vary with DDCL proportion. The slope of injection rate versus setting rail pressure declines as IPW lengthens. The relative phase of maximum injection rate is delayed with increasing injection pulse width. But it remains unchanged or advances as setting rail pressure increases. At the same setting rail pressure, average injection rate increases first rapidly then slowly with prolonged injection pulse width; the average injection rate of DDCL is larger than that of petrodiesel. The penetrations of spray remain almost constant in all blends. However, the steady cone angle increases with an increase in DDCL proportion. The spray tip penetration of DDCL-petrodiesel blends is prolonged by higher setting rail pressure, longer IPW, and lower ambient pressure. The steady cone angle is enlarged by higher setting rail pressure and ambient pressure.
COMPARISON AND CROSS-VALIDATION OF OPTICAL TECHNIQUES IN DIFFERENT SWIRL SPRAY REGIMES
697-724
10.1615/AtomizSpr.2013008110
Joshua
Lee
University of Central Florida, Orlando, USA
Saptarshi
Basu
Department of Mechanical Engineering, Indian Institute of Science Bangalore, Bengaluru 560012, Karnataka, India
Ranganathan
Kumar
University of Central Florida, Orlando, USA
hydraulic nozzles
PDPA
PIV
droplet distribution
shadowgraphy
This paper deals with an experimental study of pressure-swirl hydraulic injector nozzles using non-intrusive optical techniques. Experiments were conducted to study atomization characteristics using two nozzles with different orifice diameters, 0.3 mm and 0.5 mm, and injection pressures, 0.3−3.5 Mpa, which correspond to Reynolds number (Rep) = 7,000−45,000, depending on nozzle utilized. Three laser diagnostic techniques were utilized: Shadowgraph, PIV (Particle Image Velocimetry), and PDPA (Phase Doppler Particle Anemometry). Measurements made in the spray in both axial and radial directions indicate that velocity, average droplet diameter profiles, and spray dynamics are highly dependent on the nozzle characteristics and injection pressure. Limitations of these techniques in the different flow regimes, related to the primary and secondary breakups as well as coalescence, are provided. Results indicate that all three techniques provide similar results throughout the different regimes. Shadowgraph and PDPA were possible in the secondary atomization and coalescence regimes while PIV measurements could be made only at the end of secondary atomization and coalescence.
CHARACTERISTICS OF ADHESION OF DIESEL FUEL ON IMPINGEMENT DISK WALL. PART 1: EFFECT OF IMPINGEMENT AREA AND INCLINATION ANGLE OF DISK
725-744
10.1615/AtomizSpr.2013008113
Mohd Zaid
Akop
Division of Mechanical Science and Technology, Faculty of Science and Technology, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma, 376-8515, Japan
Yoshio
Zama
Division of Mechanical Science and Technology, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma, Japan, 376-8515
Tomohiko
Furuhata
Division of Mechanical Science and Technology, Faculty of Science and Technology, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma, 376-8515, Japan
Masataka
Arai
Division of Mechanical Science and Technology, Faculty of Science and Technology, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma, 376-8515, Japan; Tokyo Denki University
Diesel spray
impingement disk
adhered fuel
inclined wall
impingement distance
injection pressure
Adhesion characteristics of diesel fuel spray impinging on a flat wall disk were investigated experimentally. Non-evaporated diesel spray was injected into a high-pressure vessel. A circular disk wall was set vertically or inclined to the spray axis to catch the adhered fuel. Various sizes of disk and inclined angles were tested in order to observe the behavior of impinging spray. The mass of the disk with adhered fuel was measured using an electronic balance, and the fuel mass adhered to the disk surface was evaluated. The adhered mass became constant with increasing disk diameter (Dd) from Dd = 25 mm to Dd = 50 mm. Moreover, the thickness of the liquid film tended to decrease with increase of injection pressure. As the inclination of disk became steeper from 0 deg to 50 deg, the adhered fuel mass ratio became lower. Further, to explain the general trend of adhered fuel mass, modified adhered mass ratios combined with disk diameter and inclination angle were introduced.
EFFECT OF FUEL DROPLET SIZE AND INJECTION TEMPERATURE ON THE PERFORMANCE OF KEROSENE-OXYGEN PULSE DETONATION ROCKET ENGINE
745-761
10.1615/AtomizSpr.2013008128
Le
Jin
School of Power and Energy, Northwestern Polytechnical University, Xian, 710072, China
Wei
Fan
School of Power & Energy, Northwestern Polytechnical University, Xi'an,
710072, China
Zhencen
Fan
School of Power and Energy, Northwestern Polytechnical University, Xi'an 710072, People's Republic of China
Haoyi
Song
School of Power and Energy, Northwestern Polytechnical University, Xian, 710072, China
thrust
specific impulse
kerosene
atomization
pressure-swirl nozzle
In this study, the effect of fuel droplet size and injection temperature on the operating performance of a kerosene-oxygen pulse detonation rocket engine was experimentally investigated. A special particle size analyzing system was utilized to measure the kerosene droplet size. In addition, another experimental test system was also established to investigate the operating performance of a kerosene-oxygen pulse detonation rocket engine at the frequency of10 Hz. Three sizes of pressure-swirl nozzles were used to the experiment. The experimental results indicated that the SMD of kerosene droplets gradually decreased as the injection temperature increased, and three temperature ranges are separately discussed. The experiment results demonstrated that higher injection temperature and smaller SMD were beneficial to improve the operating performance. The thrust and specific impulse were very sensitive to the SMD value. As the injection temperature of the PDRE increased from 293 to 493K, the thrust increased by 23.42, 14.38, and 19.53%, and the specific impulse increased by 21.62, 19.61, and 15.89%, for nozzles 1, 2, and 3, respectively.