68 research outputs found
Training students to develop creative and innovative talents
Creativity is the ability of a person that enables him/her to think of, dream up or visualize unusual solution to a problem. It plays an important part in the development of a nation. Generally, a creative process involves five significant steps: first insight, preparation, incubation, illumination and verification. Innovation, on the other hand, is the process of reducing creative ideas to practice, making some systems, components or equipment. The success of a creative process depends to a great extent on the individual, and the environment that exists around him / her. The generation of ideas is considered one of the most important elements, where brain-storming plays an important role, which is subjected to stringent evaluation process before being implemented. An encouragement and support from educators towards creative signs of students would help in the development of creativity. An awareness of creative and innovative process and an involvement in the solution of a creative problem may help students to develop creative and innovative talents. To promote creativity and innovation, areas e.g. projects, laboratory experiments, design of systems and components, where opportunities exist for the development of creativity, should be identified to play an active role in it
Desalination: conversion of seawater to freshwater
Desalination methods are used to convert saline/brackish water to drinkable freshwater. Major processes use either thermal energy (conventional distillation) or pressure energy (Reverse osmosis). Different methods of desalination are discussed and their influence on overall water production has been highlighted. With the increase in appreciation for a green technology, desalination methods using renewable/waste energy are drawing significant attention in recent years. Applying different methods of desalination for coastal areas in Peninsular Malaysia can be very promising in terms of overall public health and economy
Desalination of seawater to provide fresh water
A comparative study of MSF, MED and RO processes has been made and the relative performance of
different methods has been discussed in this study. RO has been showing a great promise, and further
developments of new membrane materials and pre-treatment processes are likely to reduce the cost of
water production dramatically. MED is making good progress. as shown by reccnt findings, and the
production cost of water is less than MSF in certain cases. Cogeneration, water and power, and
hybrid system are likely to be the future direction
Engineering design: an approach to the development creativity
In a competitive world with limited resources, it is important to train our students in creativity. To
maintain an edge over others, it is essential to produce unusual solutions to problems and challenges.
Training students in divergent thinking is considered an essential element in the development of
creativity. Ideas, whatever the nature may be, must be respected and encouraged. Engineering design
enables students to be trained in creativity. Torrance tests provide a measure of originality, fluency,
flexibility and elaboration
Optimization of an integrated solar heat-pump system
This paper describes a method of economic optimization of an integrated solar heat pump system for
space cooling, water heating and drying. The system can serve three functions simultaneously or
independently. A simulation model for this system was developed to study the influence different
variables. The results were validated by a series of experiments carried out under the meteorological
conditions of Singapore. Based on this simulation model, an economic optimization was performed to
identify the best collector size tor a given load and its distribution. using two methods, life cycle savings
(LCS) and payback period. The load pattern is determined based on a typical small hotel with the air-con
room area of 500m2, daily hot water demand of 18m3 and daily drying demand of 90 kg. It was seen that
the life cycle saving method lead to the prediction of the optimum collector area of 55 m2. The payback
period analyses predicted the optimum collector area of 50 m2. The minimum payback period is about 1.5
years
Analyses of motion and drag coefficient of water droplets in a natural draught cooling tower
Cooling towers have been widely used in power plants and space air conditioning systems. The rain
region plays an important role in the operation of cooling towers. In this paper, four different models
have been investigated that describe the motion of water droplets in the rain region of a cooling tower.
Due to the non-uniformity of the flow, heat and mass transfer processes inside the cooling tower, the
velocity field of water droplets is, at least, two-dimensional. Therefore, these models were tested with
a numerical simulation program that accounts for the non-uniform now. The velocity fields of water
droplets, the variations of the drag coefficient with the relative velocity of water droplets have been
predicted. The effect of drag and buoyancy force on the motion of water droplets were also studied
numerically. The model based on Dreyer and Erens's correlation has been found to represent the
actual situation reasonably well and is recommended for the modelling of water droplets motion in
cooling towers
An experimental study of a phase change storage system
This paper describes the heat transfer process and the movement of the solid-liquid interface when the
energy is added to a PCM, paraffin wax, through a vertical wall heated under conditions of uniform
heat flux and constant temperature. Experiments indicate that the initial mode of heat transfer in the
melting process was purely conduction controlled, and early convection due to volumetric expansion
of the liquid PCM was followed by the solely buoyancy driven natural convection within the liquid.
At this stage, the superheating of the liquid led to a combined convection and conduction mode of
heat transfer until eventually conduction became the dominant mode of heat transfer. Superheating
and subcooling of the PCM reduce the rate of propagation of the solid-liquid interface. Numerical
simulation, based on the enthalpy formulation, indicated the presence of convection in the fluid region
of the PCM, which is confirmed by the results from the experiments
Drying under inert environment: the quality of Mango and Rockmelon
Extensive tests were carried out on the quality related properties, such as flavor, appearance, texture and
nutritional values of mango and rockmelon samples dried under normal air heat pump dryer (HPD),
modified atmosphere heat pump dryer (MAHPD) using N2, and CO2 and also vacuum and freeze dryers.
For mangoes and rockmelons, the MAHPD dried samples show better flavor than HPD dried samples.
The freeze and vacuum dried samplcs are considered even better than MAHPD dried samples, although at
a much higher costs. For MAHPD, N2, drying leads to a better color retention than CO2, drying. The HPD
dried samples show a higher value of textural hardness than MAHPD samples, whereas the freeze dried
samples show the lowest textural hardness. Freeze drying leads to the best vitamin C retention, followed
by vacuum, MAHPD and HPD drying. In the case of MAHPD, the CO2, drying shows slightly higher
retention of vitamin C than N2
Solar drying of guavas, papayas and apples
This paper includes the results of a study carried out to determine the drying characteristics of three
agricultural fruit products. The products used in this analysis were apples, guavas and papayas. The
drying characteristics of the three products were investigated under different operating conditions by
varying now velocities and the thickness of the specimens. An experimental solar dryer was built to
conduct tests on different samples. Tests were carried under both natural and forced convection
conditions. Different meteorological conditions were considered in the experiments. A analytical model.
based on Fick's second law of diffusion. was used to determine the effective diffusion coefficients of the
three products. The diffusion coefficients were obtained from the slope of in (w/wo) against t/L2. It was
found that the diffusivities of apples, guavas and papayas range between 5.74xI0-12 and 8.6IxI0-IO
1112/s. It was also observed that shrinkage occurred in the above three specimens during drying. This effect
was taken into account and a correction factor for thickness, L, was introduced
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