An Experimental Study of the Vaporization Characteristics of Diesel-Benzyl Azides Blend Droplets

2013 ◽  
Author(s):  
Kai Han ◽  
Geng Fu ◽  
Changlu Zhao ◽  
Bolan Liu ◽  
Shibo Ma
Keyword(s):  
Experimental Study ◽  
Ambient Temperature ◽  
Atmospheric Pressure ◽  
High Speed ◽  
Droplet Diameter ◽  
Video Camera ◽  
Initial Droplet ◽  
High Speed Video Camera ◽  
Combustion Duration ◽  
Suspended Droplet

An experimental study of diesel-benzyl azides blend droplets vaporization characteristics was carried out to study the reasons of diesel-benzyl azides blend shortened combustion duration using suspended droplet device and a high-speed video camera. Experiments were performed at atmospheric pressure, ambient temperature range 480–933 K, and initial droplet diameter of 0.98, 1.42, 1.88 mm. The results show a shorten in diesel-benzyl azides blend droplet lifetime by 10% compared to diesel droplet at 1.42 mm initial droplet diameter and 933 K ambient temperature companion to puffing. The above results support the original idea of designing diesel-benzyl azides blend where the energy released by the decomposition of azides improves the vaporization and the release of nitrogen leads to the breakup of the droplet. In addition, it is observed that the blend lifetime decrease with increasing ambient temperature compared to diesel droplet lifetime. More nitrogen is released and the expansion of bubbles is more violent with increasing initial droplet diameter.

scholarly journals Thermocapillary rupture of a horizontal liquid layer on a silicon substrate

2019 ◽  
Vol 196 ◽  
pp. 00041
Author(s):  
Dmitry Kochkin ◽  
Valentin Belosludtsev ◽  
Veronica Sulyaeva
Keyword(s):  
Experimental Study ◽  
Contact Line ◽  
High Speed ◽  
Video Camera ◽  
Phase Contact ◽  
High Speed Video ◽  
High Speed Video Camera ◽  
Three Phase ◽  
Breakdown Phenomenon ◽  
Dry Spot

This paper is an experimental study of thermocapillary breakdown phenomenon in a horizontal film of liquid placed on a silicon nonisothermal substrate. With the help of a high-speed video camera the speed of the three-phase contact line was measured during the growth of a dry spot.

scholarly journals EXPERIMENTAL STUDY ON THE PHENOMENA ON THE SUCCESSIVE DROPLETS IMPACTING HOT COPPER SURFAC

2019 ◽  
Vol 24 (2) ◽  
pp. 129-142
Author(s):  
Arif Widyatama ◽  
Akmal Irfan Majid ◽  
Teguh Wibowo ◽  
Deendarlianto Deendarlianto ◽  
Samsul Kamal
Keyword(s):  
Image Processing ◽  
High Speed ◽  
Droplet Diameter ◽  
Video Camera ◽  
Processing Technique ◽  
Image Processing Technique ◽  
High Speed Video ◽  
High Speed Video Camera ◽  
Diameter Droplet ◽  
Apex Height

This study was aimed at investigating the phenomena and interactions between water droplets and hot metal surfaces using an experimental method. In this study, the droplet was dropped from 50 mm from the top of the metal surface with a frequency of 8.5 droplets per second. The observed droplet diameter was 3.12 mm. The metal used was copper with a surface temperature between 110-240 ° C. High speed video camera with a speed of 2000 fps was used to record visual data. Then the image processing technique was applied to calculate the change in droplet diameter. The results show that at low temperatures, droplets tend to maintain their initial position of contact with fluctuating deformations. While at high temperatures, a bounce phenomenon occurs which results in collisions between droplets being imperfect. Visualization results can reveal the complete change in the droplet geometry in the form of spreading ratio and complete apex height. The temperature of 140° C is the initial transition area for phenomena that result in droplets has no contact with hot surfaces so that the process of heat transfer between surfaces is inhibited.STUDI EKSPERIMEN PADA FENOMENA SUCCESSIVE DROPLETS MENUMBUK PERMUKAAN TEMBAGA PANASPenelitian ini bertujuan untuk mempelajari fenomena dan interaksi antara tetesan air (droplet) dan permukaan logam panas dengan metode eksperimental. Pada penelitian ini, droplet dijatuhkan dari posisi 50 mm dari atas permukaan logam dengan frekuensi 8,5 droplet per detik. Diameter droplet yang diamati sebesar 3,12 mm. Logam yang digunakan adalah tembaga dengan temperatur permukaan di antara 110-240° C. High speed video camera dengan kecepatan 2000 fps digunakan untuk merekam data visual. Teknik image processing diaplikasikan untuk menghitung perubahan diameter droplet. Hasil penelitian menunjukkan bahwa pertama, pada temperatur rendah, droplet cenderung mempertahankan posisi awal kontak dengan perubahan bentuk yang fluktuatif. Kedua, temperatur tinggi, terjadi fenomena bouncing yang mengakibatkan tumbukan antar droplet menjadi tidak sempurna. Hasil visualisasi dapat mengungkap perubahan geometri droplet berupa spreading ratio dan apex height secara lengkap. Dari penelitian ini juga diketahui bahwa temperatur 140°C menjadi daerah transisi awal terjadinya fenomena yang mengakibatkan droplet tidak bersinggungan dengan permukaan panas sehingga proses perpindahan kalor antar permukaan terhambat.

scholarly journals Autoignition Behavior of an Ethanol-Methylcellulose Gel Droplet in a Hot Environment

Energies ◽  
2018 ◽  
Vol 11 (8) ◽  
pp. 2168 ◽  
Author(s):  
Donggi Lee ◽  
Jonghan Won ◽  
Seung Baek ◽  
Hyemin Kim
Keyword(s):  
Ambient Temperature ◽  
Ignition Delay ◽  
Atmospheric Pressure ◽  
Droplet Diameter ◽  
Experimental Studies ◽  
Sudden Increase ◽  
Pure Ethanol ◽  
Initial Droplet ◽  
Hot Environment ◽  
Ignition And Combustion

Autoignition of an ethanol-based gel droplet was experimentally investigated by adding 10 wt % of methylcellulose as gellant to liquid ethanol. Experimental studies of the ignition behavior of the gel droplet were found to be quite rare. The initial droplet diameter was 1.17 ± 0.23 mm. The gel droplet was suspended on a K-type thermocouple and its evaporation, ignition and combustion characteristics were evaluated and compared with pure ethanol at an ambient temperature of 600, 700, and 800 °C under atmospheric pressure conditions. The gel droplet exhibited swelling and vapor jetting phenomena. Before ignition, a linear decrease in droplet diameter followed by a sudden increase was repeatedly observed, which was caused by evaporation and swelling processes, respectively. Major droplet swelling was detected just before the onset of ignition at all temperatures. But no further swelling was detected after ignition. For the gel droplet, the ignition delay accounted for 93% of the droplet lifetime at 600 °C, and 88% at 700 °C, but only 31% at 800 °C. Its average burning rate was also evaluated for all temperatures. At 800 °C, the gellant layer no longer exerts any influence on the combustion of the gel droplet.

scholarly journals Detonation effects of shallow buried explosive in sandy soil on target plate acceleration in a small-scale blast test

2018 ◽  
Vol 192 ◽  
pp. 02028
Author(s):  
Hassan Zulkifli Abu ◽  
Ibrahim Aniza ◽  
Mohamad Nor Norazman
Keyword(s):  
Sandy Soil ◽  
High Speed ◽  
Early Stage ◽  
Time History ◽  
Video Camera ◽  
Small Scale ◽  
Target Plate ◽  
Air Blast ◽  
High Speed Video Camera ◽  
The Impact

Small-scale blast tests were carried out to observe and measure the influence of sandy soil towards explosive blast intensity. The tests were to simulate blast impact imparted by anti-vehicular landmine to a lightweight armoured vehicle (LAV). Time of occurrence of the three phases of detonation phase in soil with respect to upward translation time of the test apparatus were recorded using high-speed video camera. At the same time the target plate acceleration was measured using shock accelerometer. It was observed that target plate deformation took place at early stage of the detonation phase before the apparatus moved vertically upwards. Previous data of acceleration-time history and velocity-time history from air blast detonation were compared. It was observed that effects of soil funnelling on blast wave together with the impact from soil ejecta may have contributed to higher blast intensity that characterized detonation in soil, where detonation in soil demonstrated higher plate velocity compared to what occurred in air blast detonation.

In Situ Observation Method for Quantitative Evaluation of Solidification Phenomena and Solidification Cracks during Welding

2014 ◽  
Vol 782 ◽  
pp. 3-7
Author(s):  
Kenji Shinozaki ◽  
Motomichi Yamamoto ◽  
Kohta Kadoi ◽  
Peng Wen
Keyword(s):  
High Speed ◽  
Video Camera ◽  
Solidification Cracking ◽  
In Situ Observation ◽  
High Speed Video Camera ◽  
Varestraint Test ◽  
Solidification Cracks ◽  
Observation Method ◽  
Solidification Crack

Solidification cracking during welding is very serious problem for practical use. Therefore, there are so many reports concerning solidification cracking. Normally, solidification cracking susceptibility of material is quantitatively evaluated using Trans-Varestraint test. On the other hand, local solidification cracking strain was tried to measure precisely using in-situ observation method, called MISO method about 30 years ago. Recently, digital high-speed video camera develops very fast and its image quality is very high. Therefore, we have started to observe solidification crack using in site observation method. In this paper, the local critical strain of a solidification crack was measured and the high temperature ductility curves of weld metals having different dilution ratios and different grain sizes to evaluate quantitatively the effects of dilution ratio and grain size on solidification cracking susceptibility by using an improved in situ observation method.

Study on Magnetic Barrel Machine Equipped with Three-Dimensional Arrangement of Magnets

2007 ◽  
Vol 329 ◽  
pp. 761-766 ◽  
Author(s):  
Y. Zhang ◽  
Masato Yoshioka ◽  
Shin-Ichiro Hira
Keyword(s):  
High Speed ◽  
Permanent Magnets ◽  
Three Dimensional ◽  
Video Camera ◽  
High Speed Video ◽  
High Speed Video Camera ◽  
The Media ◽  
Set Up

At present, a commercially available magnetic barrel machine equipped with permanent magnets has some faults arising from constructional reason. That is, grinding or finishing ability is different from place to place in the machining region, resulting in the limitation on the region we can use in the container of workpieces. Therefore, in this research, authors made the new magnetic barrel machine equipped with three dimensional (3D) magnet arrangement to overcome these faults. The grinding ability of the new 3D magnetic barrel machine converted was experimentally examined, and compared with that of the traditional magnetic barrel machine. As a result, it was shown that we can use much broader region in the new 3D machine. It was also shown that the grinding ability became higher. The distribution of barrel media in action was recorded by means of a high speed video camera. It was clarified that the media rose up higher and were distributed more uniformly in the container by the effect of the magnet block newly set up. It was supposed that this must be the reason for the above-mentioned improvement of grinding ability.

Grease soap particles passing through an elastohydrodynamic contact under side slip conditions

2000 ◽  
Vol 214 (4) ◽  
pp. 317-325 ◽  
Author(s):  
P Eriksson ◽  
V Wikström ◽  
R Larsson
Keyword(s):  
Film Thickness ◽  
High Speed ◽  
Previous Investigation ◽  
Video Camera ◽  
Slip Conditions ◽  
High Speed Video ◽  
Elastohydrodynamic Contact ◽  
High Speed Video Camera ◽  
Pure Rolling ◽  
Minimum Film Thickness

In a previous investigation, grease thickener fibres were tracked as they passed through an elastohydrodynamic (EHD) contact in pure rolling using interferometry in a standard ball-and-disc apparatus. In order to capture single thickener fibres, a high-speed video camera was used. Here, the experiments have been repeated introducing different amounts of side slip for different rolling speeds and a faster video camera capable of capturing 4500 frames/s. The contact was lubricated with a continuous supply of grease. Two greases, based on the same synthetic poly(α-olefin) but thickened with Li-12-OH and lithium complex soap respectively, were studied. It was observed that the thickener fibres were stretched both before entering the contact and as they passed through it. Fibres seem to avoid the minimum film thickness regions and, if they enter, the film is restored immediately after passage.

Biomechanical Analysis of a World Record Javelin Throw: A Case Study

1985 ◽  
Vol 1 (1) ◽  
pp. 73-77 ◽  
Author(s):  
Robert J. Gregor ◽  
Marilyn Pink
Keyword(s):  
High Speed ◽  
Video Camera ◽  
The United States ◽  
Track And Field ◽  
Biomechanical Analysis ◽  
World Record ◽  
High Speed Video ◽  
High Speed Video Camera ◽  
Ongoing Project

As part of an ongoing project to evaluate elite track and field throwers in the United States, the javelin competition was filmed during the 1983 Pepsi Invitational Track Meet. A high-speed video camera (Spin Physics SP2000) was positioned orthogonal to the javelin runway to record the release of all throws. During this competition, Tom Petranoff’s world record (99.72 m) was filmed at 200 fields per second. Subsequent frame-by-frame digitization yielded results consistent with reports in the literature. Release velocity was 32.3 m/s and represents one of the highest values ever reported. Angle of release was .57r, javelin attitude at release was .64r» and angle of attack was .07r. While optimum values for these release parameters, in light of published results, remain open to discussion, the results presented here represent unique information on a world record performance and can serve as a basis of comparison for future performances.

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