International Journal of Mechanical Engineering

11-20

Authors: Abdulrahman S. Sait & Yaser A. Hadi

This task clarifies an instantaneous angular speed (IAS) test technique that is robust for engine condition monitoring (CM). The pivot of the crankshaft is dependent on the cylinder speed, determined using the situation in this study. The tests and the research discussed in this project offer a thorough understanding of the harmful implications for the quick angular speed. Moreover, using the angular move procedure it demonstrates the subtleties in crankshaft motion. The optical encoder is used to obtain data about angular motion.In the stage region, the sign was acquired and broken using the sign average to decide the weaknesses and their location. National instruments are used and programming code for NI LabView is produced for ongoing use. Optical encoders are tentatively investigated by implementing IAS studies under multiple operating circumstances to cylinders that issue recognition devices.

31-44

Authors: Faisal M SH F Alazemi & Mohd Radzi Haji Che Daud

For a plant engineer, the boiler efficiency is one of the most crucial aspects. Therefore, different techniques are developed to improve the boiler performance. In the several studies, it is found that a boiler consumes the energy around eighty percent of the boiler operating cost.The efficiency of a boiler suffered due to the various losses occurred. These losses are mainly occurred due to the flue gas accumulation, unburned fuel, convective and radiated heat loss.To improve the efficiency of a boiler, the design optimization is studied in this research. In this study, several parameters such as pre-heater design, economizer design, an efficient heating system design, etc., are used.In a boiler, heat loss is very high when the flue gas released almost thirty percent of the energy loses due it. Therefore, it is essential to optimize the design of a boiler so that the performance can be improved.In a boiler design, complex geometry is used because it has multiple inputs and multiple outputs. This system is of a non-linear type which has no self-balancing mechanism. The combustion process of a boiler is also complicated in terms of physical as well as chemical process. A boiler is used for various applications such as food industries, cement industries, etc. The efficiency of a boiler is required to improve due to multiple reasons such as energy savings, low maintenance cost, and environmental safety, etc. Recent days, everyone is developing a design that can help in energy conservation on the urge of pressing environmental issues such as global warming. In several industries and power plants, boilers are primarily used for generating steams or producing hot water. Several studies showed that the consumption of energy in boilers is significant (M.C. Barama et al. 2017). Therefore, improving the boiler efficiency even in small amount can lead to save a significant amount of energy. It can also help to improve the carbon emission that will be a significant step towards the environmental safety. By definition, a boiler is a pressure vessel which is used for generating electricity or supplying the hot water to the industry for providing the heating facilities depending upon the requirements. In some commercial and residential buildings, boilers are used for providing hot water or steam facilities for various domestic and commercial purposes (L. Jaymaha, 2006). In all over the world for generating electricity, coal, gas, etc., and nuclear power is primarily used. For converting energy generated by these resources, for example, thermal energy into electricity, boilers are one of the suitable options. The fossil fuels reserves are depleted day by day and the demand for other energy resources such as oil, gas, and coals, etc., for electricity production are increasing. According to a study, these energy resources demands will reach 47.5% - 94.7% by the end of 2030 (M.C. Barma et al., 2017), (S. Som and A. Dutta, 2008). Therefore, improvement in boiler efficiency is crucial. In a steam boiler, chemical energy obtained from the fuel is transformed into the thermal energy with the help of combusting fuels in the furnace. These days the design of a boiler are getting more complex as more number of equipment are connected such as heat exchanger, pre-heater, economizer, etc.

7-20

Authors: Janvier Kamanzi Impact Factor

An estimate of more than a hundred million landmines laid across multiple countries is undetonated, while lots of new landmines are being planted to this day. Through history, people have been investing effort in developing safe and accurate technologies in response to the ever-increasing figures of landmines. Some of these technologies include animal detection, prodding, mine clearing vehicles, ground penetrating radar and hand-held metal detectors. Although these technologies have each had their success in reducing the landmine count across the world, they still do have disadvantages. In the process of developing a novel technology, this paper covers a literature review on existing technologies and highlighted that their critical shortfall pertain to the safety of the operator. Most of the existing technologies require operators to move the detecting systems in places where landmines are to be uncovered, thus putting their life at risk. The paper provides an overview of research done into metal detectors. The paper then describes the design of a remotely controlled vehicle dedicated for landmine detection. The system design describes how the different parts of the design comes together to create a working system. Each major component is thoroughly described along with the motivation behind the component selection. Firmware, circuit design and each aspect of the design are detailed. The paper concludes that a fully functioning and collision-avoiding prototype has been successfully developed to detect landmines using a webpage and a built-in metal detector. Finally, a room for improvement on the design has been indicated.

7-14

Authors: S. Venkateswarlu, G. Narendra, B. Sriram Achari, G.V.Lahari, K.Umesh Chandra & S. Anwar Basha

Automobile chassis is one of the major elements of road motor vehicles. Normally automobile is divided into two parts they are Body and Chassis. Thus this chassis design and analysis form the most important stage of vehicle manufacturing. It is a basic structure of a vehicle. Chassis is the integral part of the vehicle it bears the entire load of the vehicle including its self-weight. A weight of chassis is one of the major influencing factors & it must be strong enough to resist shocks, twist, vibrations and stresses [1]. In designing of chassis frame maximum stress and maximum deflections are the important factors. Static analysis of chassis is carried out by finite element method and we obtain the results like stress & deformation. The most suitable method for analysis is the finite element method [2]. A three-dimensional chassis model is created in Creo 5.0 imposed in ANSYS 18.2. Finite element analysis truck chassis was carried out using ANSYS & its static behavior was studied taking 3 different types of materials like Steel, Aluminum alloy, Carbon steels

23-44

Authors: Yasin K. Salman & Hussam Fiesal Abed Hmood

The step height effect of radially inward expanded air flow stream on the heat transfer process in a concentric circular annular passage is studied experimentally. The air flow separation, reattachment and redevelopment took place in the test section which its inner tube subjected to a constant heat flux boundary condition. The experimental apparatus comprised of concentric tubes to form an annular passage with a sudden enlargement in the passage cross-section created by increasing the outer tube diameter of the annular inner tube at the entrance section prior to the test section. The inner tube of the test section was made of aluminium having 25 mm outside diameter and 350 mm heated lengths, which was subjected to a constant wall heat flux boundary condition.The investigation was performed to cover a Re range of 3000 – 11000, inner tube heat flux varied from 800 W/m2 to 1750 W/m2 and the enhancement of step heights were S = 0 ( without step), 6.5 mm, 12.5 mm, and 18.5 mm which refer to Di /d = 1, 1.5, 2 and 2.5, respectively. Results reveal for all cases, that the local heat transfer coefficient increased against increasing the heat flux and/or Re. The step height has an eminent effect on heat transfer in the separation region which decreases with the raise of the step height. The passage without step (S=0) results were correlated and compared with the availableturbulentforced convectionentry length correlations for same geometry and boundary conditions. The step height effects show, for S= 6.5 mm a 25% on the average improvement in heat transfer for a full Reynolds number tested while for another two step heights the results show a limited improvement in low Reynolds number to a 16.5% reduction in heat transfer due to separation zone effect. The velocity profiles demonstrate that the position of reattached point behind the step increases with the rise of step height.The present results show a good agreement with the available previous works and have followed similar trends.

15-26

Authors: Bangarappa. L& Thammaiah Gowda

The data presented shows a dependence of natural frequencies, peak amplitudes and damping levels of four audio vibration modes in the different frequency range up to 1000 Hz on crack types and crack locations. Data from defective single crystalline wafers exhibit lower natural frequencies, higher damping levels, and lower peak amplitudes. From the results suggest an impact test method may be very useful for solar cell crack detection and quality control in the photovoltaic industry. The aim is to experimentally conduct and detect cracks from vibration measurements introduced by striking the single silicon wafer with an impact hammer. Such a method would reduce costs in the production of solar cells or photovoltaic industry

5-10

Authors: Oyetunji Oluremilekun Ropo, Pele Babatope Olabanji &Orisawayi Abimbola Oluwatayo

The progress in the metallurgical field in Nigeria has called for an increase in demand for refractory materials in recent times. A large proportion of these materials are currently being imported to meet its increasing demand. Therefore, this stirs up the need to investigate the properties of suitable locally made refractory. This study presents the results of comparative analysis and evaluation of the refractory properties of some prepared dolomite purchased at Ilorin using clay deposit in OrileIgbon, Ogbomosho, Nigeria as an additive with a view of improving the suitability of dolomite uses as a refractory material. The test carried out, revealed that the dolomite and water has a bulk density between 1.27 – 2.05g/cm3, linear shrinkage between 0 - 0.73%, 12-17 cycles for thermal resistance and a value between 0.21 and 0.34KN/cm2 for cold crushing strength, dolomite, water and honey has a bulk density between 1.61 – 3.03g/cm3, linear shrinkage between 0 - 0.74%, 12-35 cycles for thermal resistance and a value between 1.11 - 2.51KN/cm2 for cold crushing strength. Dolomite, clay, water, and honey has a bulk density between 1.72 – 2.56g/cm3, linear shrinkage between 0 - 0.76%, 19-42 cycles for thermal resistance and a value between 1.41 and 2.57KN/cm2 for cold crushing strength and clay and water has a bulk density between 1.93 – 2.44g/cm3, linear shrinkage between 0 - 8.70%, 22-42 cycles for thermal resistance and a value between 2.90-3.95KN/cm2 for cold crushing strength which shows that the investigated properties, the mixture (clay and dolomite) and clay alone are better refractory materials and suitable for lining of furnace where the materials melted requires basic environmental and operating temperature above 1100oC than dolomite alone