Design and Analysis of MEMS-based Microballoon Actuators for Aerodynamic Control of Flight Vehicles

The development of microelectromechanical systems (MEMS) technology and the suitability and compatibility of sizes of microactuators with the boundary layer thickness fueled the active flow separation control to gain the air flow momentum for the last few years. The present paper deals with the development of a robust, largedeflection, and large-force MEMS-based microballoon actuator for aerodynamic control of flight vehicles such as projectiles, micro air vehicles, aircrafts, etc. Experiments were carried out on the scaled-up models for different input pressure conditions to study the response of microballoon actuator. To evaluate the performance of the microballoon actuators, simulation studies on MEMS scale models were conducted in the CoventorWare environment. Simulation studies involving static and dynamic analyses have been carried-out on the microballoon actuator models. Various geometric and input parameters influencing the behaviour of the microballoon actuator were investigated. It has been observed that a maximum deflection of 1.2 mm to 1.5 mm can be achieved using microballoon actuators and the maximum operational frequency of 60 Hz to 80 Hz can be used for the operation of microballoon actuators. Also, the sizes of the microballoon actuators designed are compatible and suitable tobe used in turbulent boundary layer of aerodynamic flight vehicles.Defence Science Journal, 2009, 59(6), pp.642-649, DOI:http://dx.doi.org/10.14429/dsj.59.157

Design of Packaging for Microballoon Actuators and Feasibility of their Integration within Aerodynamic Flight Vehicle

The microballoon actuators are used for the active flow control in turbulent boundary layer for aerodynamic control of flight vehicles. The packaging, interfacing, and integration of the microballoon actuators within the flight vehicle play a key role for functioning of the microballoon actuators during the flight conditions. This paper addresses the design and analysis of packaging and integration aspects and associated issues. The use of microballoon actuators on the control surfaces and nose cone of flight vehicles has the positive influence of delaying the flow separation from the aerodynamic surface. This results in enhancing aerodynamic effectiveness and lift as well as reduction of drag. A typical control surface is configured with eight microballoon actuators symmetric wrt the hinge line of the control surface and embedded within the control surface. Provision of the Pneumatic feed line system for inflation and deflation of the microballoons within the control surface has been made. The nose cone has been designed to have 32 such actuators at the circular periphery. The design is found to be completely feasible for the incorporation of microballoon actuators, both in the nose cone and in the control surface.Defence Science Journal, 2009, 59(5), pp.485-493, DOI:http://dx.doi.org/10.14429/dsj.59.154

Forward Sweeping Method for Solving Radial Distribution Networks

ABSTRACT: Practical rural distribution feeders have failed to converge while using NR and FDLF methods. Therefore, a new load flow technique for radial distribution networks by using node and branch numbering scheme will be developed. In the forward sweep, the voltage at each downstream bus is then updated by the real and imaginary components of the calculated bus voltages. The procedure stops after the mismatch of the calculated and specified Voltages at the substation is less than a convergence tolerance. A Forward sweeping method for solving radial distribution networks will be implemented. Thus, computationally, the proposed method will be a very efficient and requires less computer memory storage as all data is stored in vector form. The load flow will be run in MATLAB for solving the equations