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Defect Minimization in Motor Body Casting
Using Analytical Calculation and Casting Simulation
with Experimental Validation
--Shailee G Acharya, Jeetendra A Vadher, M V Sheladiya and Mahesh Madhnani
The pouring of liquid metal into mold is one of the foremost crucial steps in manufacturing castings. The behavior of the liquid and its resultant hardening and cooling confirm whether or not the solid form is going to be properly shaped, internally sound and free from casting defects. The fluid flow phenomena throughout mold filling area unit offensively advanced. It is offensively tough to analyze these phenomena through experimentation. Comprehensive, smooth and uniform filling of mold with molten metal is achieved by an appropriate gating system, which contains pouring basin, single or multiple sprues, runners and gates. Location, shape and size of the gating components define the sequence and flow rate of molten metal into the mold cavity. A technique for optimizing the gating system design parameters of a motor cover casting based on the casting design analytical calculation and casting solidification simulation is proposed. Mold filling and solidification processes of the motor cover casting were simulated with the online e-foundry web resource which is developed by IIT-Bombay, India. The results of simulating software indicated that the quality of the motor cover casting is affected by gating system parameters in a significant manner. The experiments were carried out at Krislur Castomech Pvt. Ltd., Bhavnagar, Gujarat, India. © 2016 IUP. All Rights Reserved.
The Effect of Major and Minor Axis
of Elliptical Shape Pin Fins on Heat Transfer
and Pressure Drop Characteristics
--Monoj Baruah, Manash Borah and H K Das
In the paper, a computational investigation of compact heat exchangers that are primarily used in dissipating heat generated by electronic components is performed for three-dimensional fluid flow and turbulent forced convective heat transfer from an array of elliptical pin fins. Aluminum was considered to be the material of pin fins. In order to assess the effect of major and minor axis of elliptical shape pin fins on the pressure drop and heat transfer capabilities, two different types of elliptical pin cross-sections of constant surface area, namely, ellipse-1.3 and ellipse- 1.4 were computationally investigated. Incompressible air as the working fluid is modeled using the Reynolds-Averaged Navier-Stokes equations. RNG k turbulence model is used to account for the effect of turbulence. Temperature field inside the fins is obtained by solving Fourier’s conduction equation. The conjugate differential equations are solved simultaneously for both solid and gas phases by the finite volume method using the SIMPLE algorithm. Pressure, temperature and velocity profiles at different locations within the computational domain are considered for different Reynolds number. The heat transfer and pressure drop characteristics are assessed in the computational domain. It is seen that heat transfer and pressure drop characteristics change with changing shape of elliptical fins by varying the major and minor axis. The results show that the overall performance of ellipse 1.4 pin fins is better than that of ellipse 1.3 pin fins. © 2016 IUP. All Rights Reserved.
Design and Synthesis of Novel
Cam-Based Continuously Variable Transmission
--Anup Sahebrao Borse and Nitin Vijay Satpute
Over the last two decades, significant research effort has been directed towards developing vehicle transmissions that reduce the energy consumption of an automobile. Good ride performance is one of the most important key attributes of a passenger vehicle. One of the methods to achieve this is by using Continuously Variable Transmission (CVT). A CVT offers a continuum of gear ratios between desired limits, which consequently enhances the fuel economy and dynamic performance of a vehicle by better matching the engine operating conditions to the variable driving scenarios. As CVT development continues, costs will be reduced and the performance will continue to improve, which will make further development and application of the CVT technology desirable. The paper deals with the design and synthesis of novel cam-based CVT. It consists of threedimensional cams/camoids and flat face oscillating followers. Camoids have profiles of constant velocity and are mounted on input shaft, and followers are mounted on output shaft. Oscillating followers are mounted on the shaft with the help of unidirectional clutches which convert the oscillating motion of followers into pure rotary motion. Speed control for the CVT is achieved by linearly traversing camoids and changing the profile of contact with followers so that transmission ratio changes. © 2016 IUP. All Rights Reserved.
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