Unsteady two-phase viscous-ideal fluid flow through a parallel plate channel under a pulsatile pressure gradient subjected to a body acceleration

G. Prabhakara Rao, S. Ravikumar, C. Vasudev and R. Siva Prasad

In this paper, we analyzed the flow of combined two-phase motion of viscous-ideal medium through a parallel plate channel under the influence of a imposed pressure gradient and a periodic body acceleration. We elucidate the development of laminar flow in such a medium, starting from the unsteady equations of incompressible two-phase of viscous-ideal fluid. The velocities in both the media and the shear stresses on the boundary plates are analytically evaluated and their behavior with reference to variations in the governing parameters is computationally discussed.

Recurrence quantification analysis to compare the machinability of steels

Ravish, Umashankar K. S., Abhinav Alva, Gangadharan K. V. and Vijay Desai

Machinability, though is a simple term, is difficult to generalize. But nevertheless, it can be realized as the ease or difficulty with which a material can be machined. Assessing the machinability of various materials before they are used in commercial manufacturing is very demanding, as the machinability affects the material removal rate, surface finish of the workpiece, cutting power consumption and tool wear rate. The present work aims at establishing Recurrence Quantification Analysis, a relatively new technique in the study of chaotic systems, as a potential tool to establish and compare the machinability of steels. The technique has its roots in quantifying the Recurrence Plots obtained by the phase space reconstruction of time domain signals. Variation in Determinism, one of the variables of the technique, is used as a mean to establish the comparison of machinability.

Cylindrical grinding of SiC particles reinforced aluminium metal matrix composites

C. Thiagarajan, R. Sivaramakrishnan and S. Somasundaram

This paper deals with an experimental study on the grindability of Al/SiC metal matrix composites in cylindrical grinding.  Machining of metal matrix composites (MMCs) is an area to be focused and finishing processes such as grinding to obtain a good surface finish and damage-free surfaces are crucial for the application of these materials. Nevertheless, grinding of MMCs has received little attention so far, thereby a detailed study on that has been carried out. In the present work, experiments are carried out to study the effect of grinding parameters; wheel velocity, work piece velocity, feed and depth of cut and SiC volume fraction percentage on the responses; grinding force, surface roughness and grinding temperature. Surface integrity of the ground surfaces is assessed using a scanning electron microscope (SEM). There are no cracks and defects found on the cylindrical ground surfaces at high wheel and work piece velocities, low feed and depth of cut.  

Investigations on the nanolayer heat transfer in nanoparticles-in-liquid suspensions

Emmanuel C. Nsofor and Tushar Gadge

Experiments have shown that nanoparticles-in-liquid suspensions (nanofluids) have higher thermal conductivities compared to the base fluids. Thus, applications of nanofluids hold enormous promise for industrial thermal energy management and similar functions. Possible parameters responsible for this increase were reviewed here leading to the development of a new correlation for the effective thermal conductivity of the nanofluid. Results show that although the thermal conductivity of the nanolayer significantly contributes to the effective thermal conductivity of the nanofluid, the nature of its variation in the nanolayer is not significant to the contribution.  Results using the correlation were compared to experimental results and correlations by other researchers. A parametric study was also performed to understand how a number of factors affect thermal conduction in nanofluids. Significant factors that influence the thermal conductivity of nanofluids were determined.

Multi-level edge detectors based on convolution matrices of base-lengths 2 and 3

Yumnam Kirani Singh

Abstract:

Proposed here is a new approach of edge detectors using edge-detecting masks generated from the basic edge detecting masks and convolution matrices of base lengths 2 and 3. The convolution matrices can be generated from a base unity matrix. These matrices behave like a low pass filter, which are effective in reducing noise in the edge detection process. The size of the convolution matrices increases with the increase in the levels. The higher the level, the generated edge detectors produce more prominent edges and have ability to suppress more noise. Experimental results show the superiority of the proposed scheme than most of the existing edge detection algorithms for different kinds of images. Algorithmically, it is simple and easy to implement.

Performance forecasting of common effluent treatment plant parameter by artificial neural network

Monika Vyas, Bharat Modhera, Vivek Vyas and A. K. Sharma

Abstract:

Use of Artificial Neural Network (ANN) models is progressively increasingly to predict waste water treatment plant variables. This forecasting helps the operators to take corrective action and manage the process accordingly as per the norms. It is a proved useful device to surmount a few of the limitations of usual mathematical models for wastewater treatment plants for the reason that of their complex mechanisms, changing aspects-dynamics and inconsistency. This analysis considers the relevance of ANN techniques to predict influent and effluent biochemical oxygen demand (BOD) for effluent treatment process. Here, a three-layered feed forward ANN, using a back propagation learning algorithm, has been applied for predicting effluent BOD. After collecting historical plant data of BOD from common effluent treatment plant at Govindpura, Bhopal (India), Efficiency of plant for removal of BOD is found to be around 80%. (3 years data collected from the influent and effluent streams of the station.) Two ANN-based models for prediction of BOD concentrations at influent and effluent points were formed. The suitable architecture of the neural network models was ascertained after several steps of training and testing of the models. The ANN-based models were established to offer an efficient and a robust tool in prediction and modeling.

A novel design of vehicle intake system detection based-on hot-film air flow meter sensors

Rong-Hua Ma

The goal of this study is to develop an airflow meter sensor for vehicle intake system detection. The study uses micro-electromechanical process technology to develop a hot-film flow meter with an alumina substrate and platinum film heater; the hotline method is used to create a micro airflow meter sensor relying on variations in resistance of the platinum film corresponding to different wind velocity at the set temperatures. The micro-sensor is less bulky and has a simpler structure than ordinary meters, and its small size enables it to provide good sensitivity and measurement precision. The alumina plate used in this study is produced by polishing an alumina substrate, and cutting the substrate to the needed size; a platinum film is then deposited on the plate to complete the micro-heater used in the sensor. The plate is then cut again to the required size. The design is also employed to fabricate single chip and double chip sensors. Resistance on the sensor side varies as gas flows through the sensor, and the instrument determines airflow velocity on the basis of the changes in resistance caused by gas flow differences. Airflow velocity of 10 m/s, 20 m/s, 30 m/s, 40 m/s, 50 m/s, and 60 m/s are used to experimentally test the sensor. Resistance displays a regular slope, indicating that the sensor can achieve its airflow velocity measurement purpose. The relationship between changes in airflow velocity and readings remain predictable throughout the sensing range. This study also varied parameters including resistance, size, direction, interval, and angle, etc. to observe the effect on sensing characteristics, and determine the best sensing model on this basis.

Workload balancing in identical parallel machine scheduling while planning in flexible manufacturing system using genetic algorithm

B. V. Raghavendra and A. N. N. Murthy

Abstract:

This paper addresses the loading problem in flexible manufacturing systems (FMSs). The problem involves the assignment of the operation or jobs to the identical parallel machine to process required part types that have been selected to be produced simultaneously. A genetic algorithm (GA) based heuristic approach is proposed in this paper for minimizing the imbalance of workload among the identical parallel machines. The program is coded in MATLAB and conducted the trials on compatible IBM/PC.  Computational results are presented in appendix and compared for different test problems to demonstrate the efficiency and effectiveness of the suggested procedure.

Monitoring and controlling fuel level of remote tanks using Aplicom 12 GSM module

Obikoya Gbenga Daniel, Ogungbaigbe Dayo and Okenu Ogoo Anne

Abstract:

This paper basically describes how fuel level in fuel tanks can remotely be controlled and monitored in order to provide a cost-effective solution to a unique challenge of fuel shortage. This was experimented with the aid of Aplicom 12 GSM Module connected to a fuel gauge of a remote tank and the variation in fuel level was remotely monitored through a compatible mobile phone. Aplicom 12 Configurator software was used to configure the Aplicom 12 GSM Module. Then, control messages were sent from a compatible mobile phone through a GSM network to the Module and response messages were sent back to the mobile phone in form of different voltage levels which correspond to the volumes of fuel in the remote tank. An equation and a graph that relates volume to voltage were established.

A model of two mutually interacting species with limited resources of first species and unlimited for second species

B. Ravindra Reddy, N. Phani Kumar and N. Ch. Pattabhiramacharyulu

Abstract:

The present paper concerns with a model of two mutually interacting species with limited resources for first species and unlimited resources for second species. The model is characterized by a coupled system of first order non-linear ordinary differential equations. In this case, we have identified two equilibrium points and described their stability criteria. Solutions for the linearized perturbed equations are also found and explained their significance. Under the limited and unlimited resources for first and second species respectively, if the death rate is greater than the birth rate for both the species, it is found that there are two equilibrium points. The stability criteria for these equilibrium points are derived and further the solutions of the linearized perturbed equations are found and illustrated.

Axisymmetric steady two-phase liquid-gas flow in a coaxial varying cylindrical space bounded internally by a rigid pipe

G. Prabhakara Rao, S. Ravikumar, C. Vasudev and R. Siva Prasad

Abstract:

In this paper, we discuss the two phase viscous-ideal flow taking place in the space between any two cylindrical pipes which approximate to an annular region bounded internally by a rigid pipe. The external boundary is coaxial non- uniform gap with no axial flow across the boundary in conformity with the symmetry. The governing nondimensional equations are solved using perturbation method with the slope of the non-uniform outer boundary very small. The velocity components both axial and radial in both the phases are evaluated and their behavior is discussed for variations in the governing parameters.

Experimental and finite elements analysis of a tuned mass absorber for vibration isolation

Abhinav Alva, Ravish and Gangadharan K. V.

Abstract:

A structure under the influence of a harmonic excitation may start vibrating violently when the applied frequency is slowly approaching any one of its natural frequencies. Resonance results in large amplitude levels and vibrations. The possible alternatives to avoid resonance are either to shift the external harmonic frequency or to change the natural frequency of the structure itself. If both the alternatives are not feasible then tuned mass absorbers can be used. The emphasis of the current work is on modeling of a tuned mass absorber to suppress the vibrations of a single degree of freedom system operating at its fundamental natural frequency. System analysis was performed using ANSYS, a commercial finite elements package. ANSYS harmonic analysis was effective in predicting safe operating frequency range for the modified structure which was also verified experimentally. Hence it can be concluded that Finite Element Analysis can be effectively used to model dynamic systems and its response, hence possible solutions could also be sought. The adaptability of the current tuned mass absorber system when subjected to varying external frequencies is a new feature of the design.

Comparative extraction of cottonseed oil by n-hexane and ethanol

Devesh K. Saxena, S. K. Sharma and S. S. Sambi

Abstract:

Cottonseed is a rich source of oil and protein. Cottonseed oil has gained importance as heart healthy oil as it contains lots of UN-saturates. It is accepted as a better medium for frying foods. Presently, n-hexane is the solvent of choice in most of the solvent extraction plants though it has been graded as highly toxic and hazardous for the environment. The present study is undertaken to explore the possibility of using ethanol as a non toxic and green solvent in place of n-hexane. The extraction of cottonseed at different temperatures, solvent-solid ratio, and particle size at different time intervals using the two solvents is presented to compare the extraction efficiency of the two solvents. The results indicate that at temperature of 45^oC and solvent to solid ratio of more than 10, ethanol has oil extraction efficiency comparable to hexane. The meal produced in the extraction process is found to have lower gossypol content when ethanol is used.

Advanced modulating techniques for diode clamped multilevel inverter fed induction motor

V. Naga Baskar Reddy, Ch. Sai. Babu and K. Suresh

Abstract:

The general function of the multilevel inverter is to synthesize a desired AC voltage from several levels of DC voltages. As the number of voltage levels increases the harmonic content decreases significantly. These multilevel inverters are used to increase inverter operating voltage, to minimize THD with low switching frequency, to reduce EMI due to lower voltage steps. The advantages of this multilevel approach include good power quality, good electromagnetic compatibility, low switching losses and high capability. This project proposes to study various multilevel inverter topologies, to simulate various modulating techniques for diode clamped multi level inverter fed induction motor. These modulating techniques include sinusoidal pulse width modulation, modified reference modulating techniques. i.e., trapezoidal reference, staircase reference, stepped reference, third harmonic injected reference and offset line voltage injected reference with triangular carrier waves. The main objective of this study is to reduce total harmonic distortion, comparison of THD and fundamental component for different modulation techniques. The Simulated Induction motor model is connected at the end to observe the Stator current harmonics and speed-torque characteristics.