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M. Sundararaj ¹, C. Yuvaraj ¹, S. Gopinath ¹, S. Elangovan ¹

Affiliations
1 Department of Aeronautical Engineering, Bharath University, Agaram then road, Selaiyur, Chennai, Tamil Nadu, IN

Abstract

Suddenly expanded flows find application in various engineering devices. The flow in the sudden expansion region is found to be affected by various factors. Passive control methods like protruding ribs are found to be very effective in the control of suddenly expanding flows. In the present study the effect of geometry of ribs on the flow characteristics is investigated computationally. The rib geometries studied are rectangular of two aspect ratios, circular, semicircular and triangular. The computational results show that rectangular rib of aspect ratio 3 significantly reduced the base pressure. The results compare very well with experimental results.

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S. Sugankumar ¹, C. Yuvaraj ¹, S. Saravanan ¹

Affiliations
1 Department of Power Electronics and Drives, Jeppiaar Engineering College, Anna University, Chennai, IN

Abstract

The selective harmonic elimination technique method has been studied using multilevel inverter in electrical drives. The selective harmonic elimination PWM method has an advantage over other harmonic PWM methods. The other methods are SHMPWM, SVMPWM where they concentrate on reducing the harmonics rather than eliminating. In the conventional method, the diode clamped three level inverter is used where in proposed method cascaded H bridge multilevel inverter is used. There are many advantages of using cascaded H bridge inverter than diode clamped multi level inverter. They are number of switches used and the levels of output produced. The simulation of the cascaded multilevel H bridge inverter has been done and the output is verified. The obtained output signal will be compared with the reference signal and then the PWM output will be obtained. In this paper three level cascaded multilevel inverter is used and the output of the inverter is given to the drives. Since the output of the inverter has harmonics which is the main cause for various loads. Such harmonics are eliminated by varying the conduction angle and the output has been verified.

Keywords

Voltage Source Inverters (VSIs), Adjustable Speed Drives (ASDs) and Uninterruptible Power Supplies (UPS).

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Thota Siva Prasad ¹, C. Yuvaraj ¹, K. Prahlada Rao ², C. K. Srinivasa ¹

Affiliations
1 Madanapalle Institute of Technology and Science, Madanapalle, IN
2 J.N.T.U.A.College of Engineering, Anantapuramu, IN

Abstract

Metal Injection Molding (MIM) is relatively a new technology for producing metal components of complex geometry. MIM is an extension of powder metallurgy process. Various products of metals and its alloys including difficult-to-machine materials such as titanium, tungsten etc., can be effectively manufactured by MIM process. MIM process comprises of four steps; mixing of metal powders with binders, injection molding of coated-metal powders to produce green parts, de-binding to separate binders from green part and the final stage is sintering. The process parameters in mixing, injection molding, de-binding and sintering play a vital role in the quality of final product.

This paper is aimed at reviewing the MIM process parameters and materials.

Keywords

MIM, Green Part, Sintering, Binder, Metal Powders, Mixing, De-Binding.

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