International Journal of Engineering and Manufacturing (IJEM)

IJEM Vol. 11, No. 3, Jun. 2021

Cover page and Table of Contents: PDF (size: 662KB)

Table Of Contents

REGULAR PAPERS

Numerical Study of Non-premixed MILD Combustion in DJHC Burner Using Eddy Dissipation Concept and Steady Diffusion Flamelet Approach

By Jarief Farabi Mohammad Ismail Ebrahim Abtahizadeh

DOI: https://doi.org/10.5815/ijem.2021.03.01, Pub. Date: 8 Jun. 2021

Numerical study simplifies the challenges associated with the study of moderate and intense low oxygen Dilution (MILD) combustion. In this study, the numerical investigation of turbulent non-premixed combustion in a Delft Co-flow Burner presents, which emulates MILD combustion behaviour. MILD combustion yields high thermal and fuel efficiency along with very low emission of pollutants. Using commercial ANSYS software, this study focuses on assessing the performance of two different turbulent-chemistry interactions models: a) Eddy Dissipation Concept (EDC) with reduced chemical kinetic schemes with 22 species (DRM 22) and b) Steady Diffusion Flamelet model, which is adopted in the Probability Density Function (PDF) approach method using chemical kinetic schemes GRI mech 3.0. The results of numerical simulations are compared with available experimental data measurement and calculated by solving the k-epsilon realizable turbulence model for two different jet fuel Reynolds numbers of 4100 and 8800. It has observed that the Steady Diffusion Flamelet PDF model approach shows moderately better agreement with the predicting temperature fields of experimental data using chemical Mechanism GRI mech 3.0 than the EDC model approach with a chemical mechanism with DRM 22. However, both models perform a better understanding for predicting the velocity field with experimental data. The models also predict and capture the effects of lift-off height (ignition kernel) with increasing of fuel jet Reynolds number, Overall, despite having more computational cost, the EDC model approach with GRI mech 3.0 yields better prediction. These featured models are suitable for the application of complex industrial combustion concentrating low emission combustion.

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Quality Analysis of Ash from Lignite Coal and its Utilization at Thar Power Plant

By Deepak Kumar Bharat Lal Mukesh Kumar Shanker Lal Meghwar

DOI: https://doi.org/10.5815/ijem.2021.03.02, Pub. Date: 8 Jun. 2021

Billion of tonnes lignite coal is deposited under the surface of Tharparkar zone had been started utilizing in its own mine mouth power plant. Tharparkar is rich in coal resource and have the potential to energize the Pakistan for at least 200 year with the deposited coal fuel of 175 Billion of tonnes. Thar coal further divided into 13 blocks; Block II (have 1% of 175 Billion of tonnes of coal has the capability of produce 5000 MW for 50 years) had just set its 2 units which is capable for 2x330 MW with coal consumption of 560 tons/hour. With the time, the increase in thermal power plant will results in increasing problems with the disposal of solid residues from combustion and off gas cleaning (Bottom ash and Fly ash). The properties of as fired coal is analyzed i.e, volatile matter, sulfur and nitrogen contents and solid residues from combustion and off gas cleaning (Bottom & Fly Ash) and it’s found that as fired coal consists of 12% ash which is 5% greater than ash of design coal that is 7% and ranges from 4-12%. Large amount of ash produced by as fired coal reaches the almost upper range of ash in designed coal and yet it’s not utilized or recycled, according to analysis it can be utilized in various forms i.e. CLC block, cements, road construction and agriculture, if it is not recycled in future then it will create bad impact to the environment like environment pollution, health concern to the human and wildlife and contaminant the under-ground water.

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The Emerging Role of Academia in Sqa

By Waqas Mahmood Syed Shaharyar Rizvi Siraj Munir

DOI: https://doi.org/10.5815/ijem.2021.03.03, Pub. Date: 8 Jun. 2021

Now that every company and every consumer prioritize quality over quantity of work, the career of Software quality assurance is also taking a leap, especially in the field of academia. Thus, this report gives an overview of what a future with the usage of software quality control and testing would look like, and why it’s needed for the development of the caliber of software used all around the globe. It further marks out why adding courses related to software quality assurance in the curriculum is important and how this addition can widen the dynamics of software control, quality and testing industries. It also marks out how, even today, academia can and is playing an integral role in the developmental process of software quality assurance and testing in terms of the research that can be and is being made towards the whole developmental process of SQA. Universities and undergraduate programs can further play an important role towards the researching the horizons and fields software testing and assurance has to offer in the near future. Furthermore, this report questioned various practitioners belonging to some of the most prestigious IT companies about their opinion on the research questions involved in this report so as to verify the credibility of the data that has been gathered. At the end of the research, we have a foresight for as to how the industry of software quality assurance and software testing will grow.

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WiFi Based Indoor Navigation System for Closed Buildings Using Smart Phones

By Gayatri Hushe Rakesh Suryawanshi

DOI: https://doi.org/10.5815/ijem.2021.03.04, Pub. Date: 8 Jun. 2021

The easy access and availability of wireless technologies and mobile computing and the internet have led to new opportunities in developing mobile applications whose purpose is to make people’s life easier. Nowadays, a person can possess more than one mobile device intended for different usage such as communication, entertainment, office work. This GPS (Global Positioning System) is one of the equipment that helps to find the way to reach the destination from the source. The use of GPS as a tool to determine the location of course has a shortage when used indoors such as Shopping Malls, Hotels, College, etc. Our project is a small attempt towards an affordable and efficient indoor navigation system in which users need to turn on mobile Wi-Fi and scan the available Wi-Fi network and its strength. If the WiFi with maximum strength is found then application will show the current location then the user can select the destination from the available options. Due to this application will show the path to the user in form of text also the application can speak the path to the selected destination.

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Comparison of Linear Quadratic – Regulator and Gaussian – Controllers’ Performance, LQR and LQG: Ball-on-Sphere System as a Case Study

By Usman Mohammed Tologon Karataev Omotayo O. Oshiga Suleiman U. Hussein Sadiq Thomas

DOI: https://doi.org/10.5815/ijem.2021.03.05, Pub. Date: 8 Jun. 2021

With the state-space method, many controllers can be designed optimally. LQR and LQG are two of these controllers. These two controllers are covered much in the literature. Despite this, not many works cover the ball-on-sphere system. Therefore, the research designed optimal LQR and LQG controllers for the system of ball-on-sphere and did a comparative analysis between the two. System dynamics were first investigated and the mathematical model was derived. After that, the system was linearized and then the state-space representation was obtained. Using this representation, the two controllers were designed and applied to the system for control. The control was done based on the specified desired system performance. Finally, the controllers' performances were analyzed and compared. Results obtained showed that both controllers met the desired system performance. With θ_x is 87.14% and θ_y is 86.43% less than their respective unregulated settling times, LQR satisfied the at least 80% performance requirement more than LQG. For LQG, θ_x is 82.35% and θ_y is 82.95% less than their respective unregulated settling times. These values are less than that of LQR. It was also observed that minimizing the total control energy leads to maximizing the total transient energy but LQG maximizes the total transient energy more than LQR. Another finding was that all states played role in regulating the controller to the desired system performance. Without regulation, LQG was found to be more efficient than LQR but in general, LQR is more efficient than LQG because, in LQG, settling time (of ball's angles) of less than 1.00 sec could not be realized. LQR is 4.79% and 3.48% more efficient than LQG in x and y directions, respectively, for the ball’s angles settling time. This research is significant because it is the first to design and do a comparative analysis of LQR and LQG controllers for the ball-on-sphere system. Therefore, bridging the existing gap in the literature is the value of this research.

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