Thenano-fluids, surfactants significantly enhance the heat transfer in pool boiling.
Enhancement might be due to change in thermo physical properties of the fluids. These
nanofluids, surfactants in pure water increases thermal conductivity of fluids, change bubble
shape and behavior and coats nano-particle on the bubble surface. Extensive experiments on
pool boiling have been conducted to study the nucleate pool boiling of pure water with and
without surfactants to find the optimum concentration of surfactant without any abnormalities.
The surfactants tested with pure water are namely Ammonium Chloride NH4Cl, and Betel nut.
The data obtained with surfactants are compared with pure water.The results of Ammonium
Chloride NH4Cl surfactant in pure water showed the heat transfer enhancement up to 2800
ppm concentration; above this range no enhancement was observed. Similarly in study of role
of Betel nut in pure water, it is observed that heat transfer enhancement is up to 500 ppm
concentration. Also the input power required to reach the critical heat flux is low as compared
to other solutions. But the major drawback is it adversely affecting the solution properties (i.e.
due to low solubility in water excess amount surfactant floats on the surface of water).
The boiling curves for different concentrations of these surfactants in pure water are plotted.
Presence of these surfactants shifts the pool boiling curves towards left. Also visual
observations of bubble behaviors in presence of these surfactants in the pure water are noted.
Heat transfer mechanism and bubble behaviors are quite different from those of pure water.
Gauge Reliability and Reproducibility i.e. R&R measurement by using ANOVA
method is the main step of the production control and quality improvement of the final outputs.
This is because, it is necessary for the operators to have particular and accurate data for
analyzing and solving problems of the production. This paper underlines the study of Gauge
R&R using ANOVA on the Minitab software for checking the tools, equipments, parts,
operators if they are not finished. It can also remove the errors of the production that gives the
In a car body weight reduction and crashworthiness are two very important
objectives of design. So reducing car’s weight and maintaining the crashworthiness in safe
limits, the idea is to replace the material of car body from mild steel to high strength steel is
brought forward. High strength steel has higher impact strength which enables us to use sheets
of reduced thickness compared to mild steel sheets, which is also verified by FEA and
simulation of car body crashing into a rigid wall. With the help of the equation derived in the
paper, sheet depth is reduced and simulation results are verified.
Composite materials are commonly used in structures that demand a high level of
mechanical performance. Their high strength to weight and stiffness to weight ratios has
facilitated the development of lighter structures. Composites are extensively used in
automotive and aviation industry due to high strength and safety requirements. Mechanically
fastened joints (such as pinned joints) are unavoidable in complex structures because of their
low cost. The requirement usually is to create holes in composite members to facilitate
mounting of various members and joints. These holes are potentially the weakest points in the
structures to determine its structural efficiency and act as stress concentration regions. In many
cases this holes are the causes of failure and the position of hole is one of the key parameter
during design. The application of single sided patch reinforcement to a composite plate with
circular fastener hole is studied using three dimensional finite element analysis. Dimension of
plate is taken as 100x300 mm with hole Dia 10 mm, while thickness of plate varying from 1 to
5 mm. One end of plate is subjected to unidirectional tensile load while other end is fixed as
shown in fig.1. These cases are simulated with and without the patch. Then effect of the patch
is experimented by taking different patch shapes into consideration.Then Comparative study is
performed for stress developed in steel and composite material. Single sided patch
reinforcement is applied to a composite plate with circular fastener hole and effect of
reinforcing patch is quantified, as shown in fig.2. Different patch shapes like circular,
rectangular, elliptical, kite, hexagonal were studied. Aparametric design is used to optimize the
suitable dimension and thickness of patch along with plate. The solution presented over here is
to cover these holes with a patch of composite lamina, which strengthen structure and reduces
the possibility of failure.
In this paper, we compare the wear behaviour of hardened and triple tempered AISI
M2 high-speed steel and the same steel that was hardened and triple tempered in conjunction
with a deep-cryogenic treatment at -185?C. Test materials were subjected to wear tests on
pin-on-disc machine in dry sliding condition. Equations were developed for predicting the
wear resistance of M2 tool steel material. Hardness data, wear loss throw light on the
improvement in wear resistance property of the M2 tool steel.
Thermal spray technique is modern coating processes which have wide variety of
materials which can be used to produce coating in such way that any material which melts
without decomposing can be used. Also it has an added advantage to strip off and recoat worn
or damaged coating without changing part properties and dimensions. But this technique has
the size limitation in coatings. The efforts through this paper are provided in such way that it
will focus on the basic and probable experimental setup to minimize or avoid disadvantages.
Field Programmable Gate Array (FPGA) technology has become a important target
for the implementation of different fusion algorithms. Image fusion is a technique that deals
with creating an image where all the objects are in focus. It is basically a process where
multiple images are combined to form a single resultant fused image. Image fusion plays an
important role to perform other tasks of image processing such as image segmentation, edge
detection, stereo matching and image enhancement. The fused image is more productive and
has better information as compared to its original input images. In this paper, Image fusion
algorithm is employed and designed based on Discrete Wavelet Transform. Software model
for image fusion using DWT has been modeled in MATLAB/Simulink. The performance of
the proposed algorithm is qualitatively evaluated by calculating Root Mean Square Error
(RMSE), Peak Signal to Noise Ratio (PSNR), Standard Deviation (SD) and Entropy of the
fused image. The algorithm will be transferred from computer to FPGA board using JTAG
cable and the fused results will be observed on Matlab.
Most secure location identify authorized person by recognizing password or person
identification no. but weakness of this system is that unauthorized person can easily discover
the password and use it without detection. Biometric recognition offers a reliable solution to
the problem of user authentication in identity management systems. But single feature
sometimes fails to be exact enough for identification or chosen feature is not always readable.
A multimodal biometric identification systems aims to fuse two or more physical or behavioral
traits to improve accuracy. An innovative approach of multimodal biometric identification
system based on iris & fingerprint trait. In system each biometric trait processes it’s
information independently and matches separately with database template. The matching score
are calculated and they are fuse with each other using sum-rule base theorem. This matching
score are compared with threshold value and final decision take either accept or reject. The
proposed multimodal biometric system will provide optimal False Acceptance Rate (FAR) &
False Rejection Rate (FRR) and improves system accuracy & dependability.
There has been a lot of growth in mobile technology over the years. A lot of standards have been designed and developed
which has brought a revolution in mobile technology. Also these standard techniques have made global communication between different sources very efficient but however the increasing global communication has also put considerable amount of burden on
the communication channels. Because the overall techniques have grown rapidly but there has been no focus given on increasing the no. of channels they are somewhat limited so sending the mobile or cellular traffic over the limited no. of communication channels requires an efficient
reuse of these channels in order to control the traffic flow. There exist different channel allocation schemes that serve this purpose. For e.g. Fixed Channel Allocation (FCA), Dynamic Channel Allocation (DCA), HCA (hybrid channel allocation) etc. Usually data transfer takes place between different cells present in the mobile network. Channels
are allocated to every cell for data transmission based on the any of the above techniques that the network might follow. For e.g. In HCA, channels are divided into two disjoint sets: one set of channels is assigned
to each cell on FCA basis, while the others are kept in a central pool for dynamic assignment . Our approach in this research work mainly focuses on improving the HCA scheme. We propose a new unique hot spot notification strategy which will send a “hot spot” notification
to the central pool in case the base station fails to allocate channels to specific cells for data transmission.