AERODYNAMICS OF WING TIP SAILS

Observers have always been fascinated by soaring birds. An interesting feature of these birds is the existence of few feathers extending from the tip of the wing. In this paper, small lifting surfaces were fitted to the tip of a NACA0012 wing in a fashion similar to that of wing tip feathers. Experimental measurements of induced drag, longitudinal static stability and trailing vortex structure were obtained.The tests showed that adding wing tip surfaces (sails) decreased the induced drag factor and increased the longitudinal static stability. Results identified two discrete appositely rotated tip vortices and showed the ability of wing tip surfaces to break them down and to diffuse them

The Effect of Computerized Instructional Program in the Intermediate First Grade Students Achievement in Arabic language Grammar in Iraq

The aim of this study was to find out the amount of influence of a Computerized Instructional Program on the achievement for intermediate first grad students in the Arabic language grammar in Iraq. The study focused on students from the first intermediate grade, in the education directorate in the Diqar governorate in Iraq.  While the study sample was intentional, that was selected by the researcher from the governorate’s schools that have computers and relevant Instructional means for education. This was represented in four branches in two groups, experimental and control group (60) male and female students in the experimental group and (60) male and female students in the control group. The researcher has utilized the Computerized Instructional Program as he study instrument for the experimental group, while the control group utilized the educational program in the usual way. The achievement test to the two groups, the experimental and the control groups, and the study reached the following results. There are no differences, with statistical significance at significance level (0.5 ≥ α), between the group’s grades average achievement in the Arabic language grammar subject. These two groups are the experimental group students who were taught by using (the Computerized Program) and students of the control group who were taught by the using the (normal) way in education. There are no differences with statistically significance at significance level(0.5 ≥ α) between the grades mean of the experimental group students who were taught by using (the computerized program) and the grades mean of the control group students who were taught by the (normal) way attribute to the gender variable (males, females). Keywords: effectiveness, computerized instructional program, achievement, arabic language, and grammar

EFFECT OF BODY SHAPE ON THE AERODYNAMICS OF PROJECTILES AT SUPERSONIC SPEEDS

An investigation has been made to predict the effects of forebody and afterbody shapes on the aerodynamic characteristics of several projectile bodies at supersonic speeds using analytical methods combined with semi-empirical design curves. The considered projectile bodies had a length-to-diameter ratio of 6.67 and included three variations of forebody shape and three variations of afterbody shape. The results, which are verified by comparison with available experimental data, indicated that the lowest drag was achieved with a cone-cylinder at the considered Mach number range. It is also shown that the drag can be reduced by boattailing the afterbody. The centre-of-pressure assumed a slightly rearward location for the ogive-cylinder configuration when compared to the configuration with boattailed afterbody where it was the most forward. With the exception of the boattailed afterbody, all the bodies indicated inherent static stability above Mach number 2 for a centre-of-gravity location at about 40% from the body nose

LAMINAR MIXING IN SMX STATIC MIXERS

This paper experimentally examines the performance of a commercial static mixer (SMX). Experiments were carried out to obtain the pressure drop across different numbers of mixing elements (4, 8, 12 and 16). The quality of mixing was visually assessed using flow visualization techniques. Experiments were performed for Reynolds number between 50 and 3000 (based on the unobstructed pipe diameter). The presence of the mixing elements in the flow stream promotes a non-laminar, turbulent-like flow which considerably enhances the mixing. Addition of more mixing elements triggered mixing in the flow at lower Reynolds numbers but this was achieved at the expense of higher pressure drop. This work represents the first stage of an on going work to develop correlations to assess the mixing quality and pressure loss in the SMX static mixers

THE INFLUENCE OF WAVE PATTERNS AND FREQUENCY ON THERMO-ACOUSTIC COOLING EFFECT

With the increasing environmental challenges, the search for an environmentally benign cooling technology that has simple and robust architecture continues. Thermo-acoustic refrigeration seems to be a promising candidate to fulfil these requirements. In this study, a simple thermo-acoustic refrigeration system was fabricated and tested. The thermo-acoustic refrigerator consists of acoustic driver (loudspeaker), resonator, stack, vacuum system and testing system. The effect of wave patterns and frequency on thermo-acoustic cooling effect was studied. It was found that a square wave pattern would yield superior cooling effects compared to other wave patterns tested

A BLUEPRINT FOR IMPLEMENTING GRAND CHALLENGE SCHOLARS’ PROGRAMME: A CASE STUDY OF TAYLOR’S UNIVERSITY

The National Academy for Engineering announced 14 Grand Challenges for the 21st Century engineers to address in order to ensure a sustainable future for the generations to come. These grand challenges are in four broad areas, namely, energy and environment, health, security and learning and computation. This paper reports on a Grand Challenges Scholars’ Programme that is developed to prepare the engineering students to be able to address the grand challenges using the CDIO framework and focusing on five components; research experience, interdisciplinary curriculum, entrepreneurship, global dimension and service learning. The programme is voluntary and the candidates are expected to commit additional learning time. The programme was launched with 16 participants who are expected to graduate in 2016. A preliminary assessment of the programs shows that the participants found the programme useful in developing an array of CDIO skills. The School intends to continue offering this programme with the intention of integrating it with a holistic education approach

Liquid air as an energy storage:A review

With the increasing demand for energy due to rapid industrialisation and the environmental concerns due to the usage of fossil fuels as the main energy source, there is a shift towards renewable energy. However, the intermittent nature of renewable energy requires energy produced during off-peak hours to be stored. This paper explores the use of liquefied air as an energy storage, the plausibility and the integration of liquefied air into existing framework, the role of liquefied air as an energy storage in addressing the Grand Challenges for Engineering as well as its employability in Malaysia