Abstract: Monocopter is a single-wing rotary flying vehicle
which has the capability of hovering. This flying vehicle includes two
dynamic parts in which more efficiency can be expected rather than
other Micro UAVs due to the extended area of wing compared to its
fuselage. Low cost and simple mechanism in comparison to other
vehicles such as helicopter are the most important specifications of
this flying vehicle.
In the previous paper we discussed the introduction of the final
system but in this paper, the experimental design process of
Monocopter and its control algorithm has been investigated in
general. Also the editorial bugs in the previous article have been
corrected and some translational ambiguities have been resolved.
Initially by constructing several prototypes and carrying out many
flight tests the main design parameters of this air vehicle were
obtained by experimental measurements. Eventually the required
main monocopter for this project was constructed. After construction
of the monocopter in order to design, implementation and testing of
control algorithms first a simple optic system used for determining
the heading angle. After doing numerous tests on Test Stand, the
control algorithm designed and timing of applying control inputs
adjusted. Then other control parameters of system were tuned in
flight tests. Eventually the final control system designed and
implemented using the AHRS sensor and the final operational tests
performed successfully.
Abstract: Among modern airflow measurement methods,
Particle Image Velocimetry (PIV) and Particle Tracking Velocimetry
(PTV), as visualized and non-instructive measurement techniques, are
playing more important role. This paper conducts a comparative
experimental study for airflow measurement employing both
techniques with the same condition. Velocity vector fields, velocity
contour fields, voticity profiles and turbulence profiles are selected as
the comparison indexes. The results show that the performance of both
PIV and PTV techniques for airflow measurement is satisfied, but
some differences between the both techniques are existed, it suggests
that selecting the measurement technique should be based on a
comprehensive consideration.
Abstract: This paper presents the application of the Discrete
Component Model for heating and evaporation to multi-component
biodiesel fuel droplets in direct injection internal combustion engines.
This model takes into account the effects of temperature gradient,
recirculation and species diffusion inside droplets. A distinctive
feature of the model used in the analysis is that it is based on the
analytical solutions to the temperature and species diffusion
equations inside the droplets. Nineteen types of biodiesel fuels are
considered. It is shown that a simplistic model, based on the
approximation of biodiesel fuel by a single component or ignoring
the diffusion of components of biodiesel fuel, leads to noticeable
errors in predicted droplet evaporation time and time evolution of
droplet surface temperature and radius.
Abstract: In this study, epoxy composite specimens reinforced
with multi-walled carbon nanotube filler were fabricated using shear
mixer and ultra-sonication processor. The mechanical and thermal
properties of the fabricated specimens were measured and evaluated.
From the electron microscope images and the results from the
measurements of tensile strengths, the specimens having 0.6 wt%
nanotube content show better dispersion and higher strength than those
of the other specimens. The Young’s moduli of the specimens
increased as the contents of the nanotube filler in the matrix were
increased. The specimen having a 0.6 wt% nanotube filler content
showed higher thermal conductivity than that of the other specimens.
While, in the measurement of thermal expansion, specimens having
0.4 and 0.6 wt% filler contents showed a lower value of thermal
expansion than that of the other specimens. On the basis of the
measured and evaluated properties of the composites, we believe that
the simple and time-saving fabrication process used in this study was
sufficient to obtain improved properties of the specimens.
Abstract: Non-destructive testing and evaluation techniques for
assessing the integrity of composite structures are essential to both
reduce manufacturing costs and out of service time of transport means
due to maintenance. In this study, Analyze into non-destructive test
characterization of carbon fiber reinforced plastics (CFRP) internal
and external defects using thermo-graphic camera and transient
thermography method. non-destructive testing were characterized by
defect size (Ø8, Ø10, Ø12, Ø14) and depth (1.2mm, 2.4mm).
Abstract: The inspection of underneath vehicle system has been
given significant attention by governments after the threat of
terrorism become more prevalent. New technologies such as mobile
robots and computer vision are led to have more secure environment.
This paper proposed that a mobile robot like Aria robot can be used
to search and inspect the bombs under parking a lot vehicle. This
robot is using fuzzy logic and subsumption algorithms to control the
robot that movies underneath the vehicle. An OpenCV library and
laser Hokuyo are added to Aria robot to complete the experiment for
under vehicle inspection. This experiment was conducted at the
indoor environment to demonstrate the efficiency of our methods to
search objects and control the robot movements under vehicle. We
got excellent results not only by controlling the robot movement but
also inspecting object by the robot camera at same time. This success
allowed us to know the requirement to construct a new cost effective
robot with more functionality.
Abstract: This paper investigates the joint effect of the
interconnected (n,k)-star network topology and Multi-Agent
automated control on restoration and reconfiguration of power
systems. With the increasing trend in development in Multi-Agent
control technologies applied to power system reconfiguration
in presence of faulty components or nodes. Fault tolerance is
becoming an important challenge in the design processes of the
distributed power system topology. Since the reconfiguration of a
power system is performed by agent communication, the (n,k)-star
interconnected network topology is studied and modeled in this
paper to optimize the process of power reconfiguration. In this paper,
we discuss the recently proposed (n,k)-star topology and examine its
properties and advantages as compared to the traditional multi-bus
power topologies. We design and simulate the topology model for
distributed power system test cases. A related lemma based on the
fault tolerance and conditional diagnosability properties is presented
and proved both theoretically and practically. The conclusion is
reached that (n,k)-star topology model has measurable advantages
compared to standard bus power systems while exhibiting fault
tolerance properties in power restoration, as well as showing
efficiency when applied to power system route discovery.
Abstract: The effect of a 3-dimensional (3D) blade on the turbine
characteristics of Wells turbine for wave energy conversion has been
investigated experimentally by model testing under steady flow
conditions in this study, in order to improve the peak efficiency and
stall characteristics. The aim of use of 3D blade is to prevent flow
separation on the suction surface near the tip. The chord length is
constant with radius and the blade profile changes gradually from the
mean radius to tip. The proposed blade profiles in the study are
NACA0015 from the hub to mean radius and NACA0025 at the tip.
The performances of Wells turbine with 3D blades has been compared
with those of the original Wells turbine, i.e., the turbine with
2-dimensional (2D) blades. As a result, it was concluded that although
the peak efficiency of Wells turbine can be improved by the use of the
proposed 3D blade, its blade does not overcome the weakness of
stalling.
Abstract: The study is devoted to define the optimal conditions
for the nitriding of pure iron at atmospheric pressure by using NH3-
Ar-C3H8 gas mixtures. After studying the mechanisms of phase
formation and mass transfer at the gas-solid interface, a mathematical
model is developed in order to predict the nitrogen transfer rate in the
solid, the ε-carbonitride layer growth rate and the nitrogen and
carbon concentration profiles. In order to validate the model and to
show its possibilities, it is compared with thermogravimetric
experiments, analyses and metallurgical observations (X-ray
diffraction, optical microscopy and electron microprobe analysis).
Results obtained allow us to demonstrate the sound correlation
between the experimental results and the theoretical predictions.
Abstract: In this paper, the dynamic characteristics of a threelobe
journal bearing lubricated with micropolar fluids are determined
by the linear stability theory. Lubricating oil containing additives and
contaminants is modelled as micropolar fluid. The modified
Reynolds equation is obtained using the micropolar lubrication theory
.The finite difference technique has been used to determine the
solution of the modified Reynolds equation. The dynamic
characteristics in terms of stiffness, damping coefficients, the critical
mass and whirl ratio are determined for various values of size of
material characteristic length and the coupling number. The
computed results show that the three-lobe bearing lubricated with
micropolar fluid exhibits better stability compared with that
lubricated with Newtonian fluid. According to the results obtained,
the effect of the parameter micropolar fluid is remarkable on the
dynamic characteristics and stability of the three-lobe bearing.
Abstract: Solar air heater is a type of heat exchanger which
transforms solar radiation into heat energy. The thermal performance
of conventional solar air heater has been found to be poor because of
the low convective heat transfer coefficient from the absorber plate to
the air. It is attributed to the formation of a very thin boundary layer
at the absorber plate surface commonly known as viscous sub-layer.
Thermal efficiency of solar air heater can be improved by providing
the artificial roughness on absorber plate is the most efficient
technique. In this paper an attempt is made to provide artificial
roughness by incorporating inclined multiple V-ribs in the underside
of the absorber plate. 60˚V – ribs are arranged inclined to the
direction of air flow. Performance of collector estimated theoretically
and experimentally. Results of the investigation reveal that thermal
efficiency of collector with multiple V-ribs increased by 14%.
Abstract: Machining parameters are very important in
determining the surface quality of any material. In the past decade,
some new engineering materials were developed for the
manufacturing industry which created a need to conduct an
investigation on the impact of the said parameters on their surface
roughness. Polyurethane (PU) block is widely used in the automotive
industry to manufacture parts such as checking fixtures that are used
to verify the dimensional accuracy of automotive parts. In this paper,
the design of experiment (DOE) was used to investigate on the effect
of the milling parameters on the PU block. Furthermore, an analysis
of the machined surface chemical composition was done using
scanning electron microscope (SEM). It was found that the surface
roughness of the PU block is severely affected when PU undergoes a
flood machining process instead of a dry condition. In addition the
stepover and the silicon content were found to be the most significant
parameters that influence the surface quality of the PU block.
Abstract: This work was one of the tasks of the
Manufacturing2Client project, whose objective was to develop a
frontal deflector to be commercialized in the automotive industry,
using new project and manufacturing methods. In this task, in
particular, it was proposed to develop the ability to predict
computationally the aerodynamic influence of flow in vehicles, in an
effort to reduce fuel consumption in vehicles from class 3 to 8. With
this aim, two deflector models were developed and their aerodynamic
performance analyzed. The aerodynamic study was done using the
Computational Fluid Dynamics (CFD) software Ansys CFX and
allowed the calculation of the drag coefficient caused by the vehicle
motion for the different configurations considered. Moreover, the
reduction of diesel consumption and carbon dioxide (CO2) emissions
associated with the optimized deflector geometry could be assessed.
Abstract: Cavitation in cryogenic liquids is widely present in
contemporary science. In the current study, we re-examine a
previously validated acoustic cavitation model which was developed
for a gas bubble in liquid water. Furthermore, simulations of
cryogenic fluids including the thermal effect, the effect of acoustic
pressure amplitude and the frequency of sound field on the bubble
dynamics are presented. A gas bubble (Helium) in liquids Nitrogen,
Oxygen and Hydrogen in an acoustic field at ambient pressure and
low temperature is investigated numerically. The results reveal that
the oscillation of the bubble in liquid Hydrogen fluctuates more than
in liquids Oxygen and Nitrogen. The oscillation of the bubble in
liquids Oxygen and Nitrogen is approximately similar.
Abstract: The paper focus on robotic telepresence system build
around humanoid robot operated with controller-less Wizard of Oz
technique. Proposed solution gives possibility to quick start acting as
a operator with short, if any, initial training.
Abstract: Cross flow water tube heat exchanger can be designed
and made operational using methods of model building and
simulation of the system. This paper projects the design and
development of a model of cross flow water tube heat-exchanger
system, simulation and validation of control analysis of different
tuning methods. Feedback and override control system is developed
using inputs acquired with the help of sensory system. A
mathematical model is formulated for analysis of system behaviour.
The temperature is regulated at the desired set point automatically.
Abstract: The objective of the present study is to determine
better eye end design of a mono leaf spring used in light motor
vehicle. A conventional 65Si7 spring steel leaf spring model with
standard eye, casted and riveted eye end are considered. The CAD
model of the leaf springs is prepared in CATIA and analyzed using
ANSYS. The standard eye, casted and riveted eye leaf springs are
subjected to similar loading conditions. The CAE analysis of the leaf
spring is performed for various parameters like deflection and Von-
Mises stress. Mass reduction of 62.9% is achieved in case of riveted
eye mono leaf spring as compared to standard eye mono leaf spring
for the same loading conditions.
Abstract: In this study the instability problem of a modified
Taylor-Couette flow between two vertical coaxial cylinders of radius
R1, R2 is considered. The modification is based on the wavy shape of
the inner cylinder surface, where inner cylinders with different
surface amplitude and wavelength are used. The study aims to
discover the effect of the inner surface geometry on the instability
phenomenon that undergoes Taylor-Couette flow. The study reveals
that the transition processes depends strongly on the amplitude and
wavelength of the inner cylinder surface and resulting in flow
instabilities that are strongly different from that encountered in the
case of the classical Taylor-Couette flow.
Abstract: Starting in 2020, an EU-wide CO2-limitation of
95 g/km is scheduled for the average of an OEMs passenger car fleet.
Taking that into consideration additional improvement measures of
the Diesel cycle are necessary in order to reduce fuel consumption
and emissions while boosting, or at the least, keeping performance
values at the same time.
The present article deals with the possibilities of an optimized
air/water charge air cooler, also called iCAC (indirect Charge Air
Cooler) for a Diesel passenger car amongst extreme-boundary
conditions. In this context, the precise objective was to show the
impact of improved intercooling with reference to the engine working
process (fuel consumption and NOx-emissions). Several extremeboundaries
- e.g. varying ambient temperatures or mountainous
routes - that will become very important in the near future regarding
RDE (Real Driving emissions) were subject of the investigation.
With the introduction of RDE in 2017 (EU6c measure), the
controversial NEDC (New European Driving Cycle) will belong to
the past and the OEMs will have to avoid harmful emissions in any
conceivable real life situation.
This is certainly going to lead to optimization-measurements at the
powertrain, which again is going to make the implementation of
iCACs, presently solely used for the premium class, more and more
attractive for compact class cars. The investigations showed a benefit
in FC between 1 and 3% for the iCAC in real world conditions.
Abstract: This paper presents optimization of makespan for ‘n’
jobs and ‘m’ machines flexible job shop scheduling problem with
sequence dependent setup time using genetic algorithm (GA)
approach. A restart scheme has also been applied to prevent the
premature convergence. Two case studies are taken into
consideration. Results are obtained by considering crossover
probability (pc = 0.85) and mutation probability (pm = 0.15). Five
simulation runs for each case study are taken and minimum value
among them is taken as optimal makespan. Results indicate that
optimal makespan can be achieved with more than one sequence of
jobs in a production order.