16 research outputs found
CHARACTERISATION OF MULTIPHASE FLUID-STRUCTURE INTERACTION USING NON-INTRUSIVE OPTICAL TECHNIQUES
The purpose of this study is to determine experimentally the effectiveness of passive drag reduction techniques (which involve adjusting surface geometry) within a chaotic multiphase flow system. To quantify the intrusion and disturbance caused, a liquid-air blast atomiser continuously discharges within a test section of air at atmospheric pressure, with a circular cylinder placed 25 cylinder diameters (250 mm) downstream of the nozzle. This cylinder is then replaced with other cylinders which have modified surface geometry. The data was obtained using Particle Image Velocimetry (PIV) and determines the fluid motion resulting from spray structure interaction of a liquid spray with a circular cylinder. Subtraction of non intruded spray images from intruded spray images at the same locations, using the time averaged analysis allows the direct comparison of the amount of disturbance each geometric variant has on the spray. Using this data alongside velocity profiles time averaged trends were compared. Drag reduction from V-shaped grooves provides the greatest disturbance reduction. This is due to the reduced shear stress around its cross section and the addition of small liquid eddies within each V-groove creates a gliding surface. These features proved to be most effective when monitoring drag reduction in multiphase flow-structure interaction
The interaction of a cold atomised spray with a circular cylinder
The development of non-intrusive diagnostic techniques has significantly increased with the introduction of lasers. Laser based anemometry, such as Laser Doppler (LDA), Phase Doppler (PDA), and Particle Image Velocimetery (PIV) can provide an accurate description of flows without interference. This study determines experimentally the fluid motion resulting from the interaction of a liquid spray with a circular cylinder. Two experimental settings were examined: the first is a discharging spray into free air and the second is a spray impinging on a circular cylinder placed 25 cylinder diameters downstream of the nozzle. These sprays were quantified using PIV. A non-intrusive droplet sizing technique was used to characterise the spray. This has shown that, within the spray, the average droplet diameter increases when the circular cylinder is introduced and so does the frequency of occurrence of these large droplets. In the wake behind the cylinder, the smaller droplets were quickly entrained and recirculated, while the larger droplets continued in the general direction of the spray cone. © School of Engineering, Taylor's University College.Published versio
Mannan extracted from (Brassica oleracea) and its use to reducing microbial contamination and oxidation indicators in frozen meat
The study was conducted in the laboratories of the College of Agriculture at the University of Basrah. In order to determine the microbial level, which included the numbers of total bacteria and cold-loving bacteria, and the level of oxidation indicators, which included the level of free fatty acids and the peroxide number when adding mannan sugar, extracted from the outer layer's leaves and applied to the meat in the freezer The results of the study showed that the average number of total bacteria decreased when adding different levels of mannan sugar compared to the control treatment. The results of the table also indicated a significant decrease in the number of total bacteria with the increase in storage periods. The average was 617.5 Cfu/g103. Before storage, it decreased to 463.1 Cfu/g103 after 90 days. The results also showed that the addition of mannan sugar at different levels led to a decrease in the numbers of cold-loving bacteria
Porosity, characterization and structural properties of natural zeolite - clinoptilolite - as a sorbent
The characterization and porous structure of raw and modified clinoptilolite as a sorbent has been investigated by nitrogen adsorption, X-ray diffraction, X-ray fluorescence, Fourier transform infrared spectroscopy, differential thermal analysis, scanning electron microscopy and atomic force microscopy methods. The nitrogen adsorption data revealed that the total pore volume and specific surface area were increased after modification. The nitrogen adsorption was used to determine percent of mesoporosity. The TG data show that 14 wt. % of clinoptilolite is lost after heating up to 1200 °C. Two types of porosities - primary porosity (microporosity) and secondary one (meso- and macroporosity) have been observed
Assessment of variations in benzene concentration produced from vehicles and gas stations in Tehran using GIS
This study investigates the variations of benzene concentration levels
in district 1, situated in the north part of Tehran, capital of Iran.
Thirty-three stations in five categories, namely roadsides, busy roads,
residential areas, traffic intersections, and the vicinity of gas
stations, were monitored during the rush hours in the afternoon once a
week over a period of 1 year. Accordingly, benzene concentration levels
were measured and predicted by inverse distance weight model. The
recorded benzene concentration levels were then compared with those
reported in other parts of the world. According to the results, the
annual concentration levels of benzene was 13.85 ppb for roads with
heavy traffic flow, 14.98 ppb for traffic intersections, 29.01 ppb for
the vicinity of the gas stations, 3.26 ppb for residential areas, and
9.97 ppb for roadsides. The concentration of benzene in the vicinity of
the gas station sampling point was higher than in the other stations,
and at all locations was found to be so much more than the standard
concentration levels (1.56 ppb) prescribed by Environmental Protection
Agency for the ambient air quality. The results of the study revealed
that the benzene concentration levels in Tehran are distinctly more
than its standard level. This is mainly attributed to the poor quality
of fuel and lack of a standard system for controlling petrol vapors in
the gas stations
THE USE OF INDUSTRIAL VISITS TO ENHANCE LEARNING AT ENGINEERING COURSES
Industrial visits represent an important activity in any engineering undergraduate programme that contributes to the achievement of various essential learning outcomes and programme objectives. This paper reports on an attempt to make the industrial visit an integral part of the Engineering Design and Communication course. This is achieved through identifying learning outcomes and a suitable industrial site to achieve them. For this purpose a thermal power plant was indentified as a site to be visited by students. The visit was planned to help students to achieve the learning outcomes. A number of questions in form of surveys, related to the learning outcomes, were prepared and given to the students to answer. The pre-visit, after-visit, and post-visit surveys were aimed at priming the minds of the students, gauging the level of satisfaction, and assessing the level of retention of knowledge, respectively. Students found this method very useful and they were able to remember a fair bit of information after about semester from the trip date. Our assessment of this exercise is the objectives have been achieved