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The application of compound pendulum theory is useful to the determination of the mass distributions of sailing boats, astronauts, farm tractors and so on. If an object is irregular in shape and if the mass distribution is not uniform then the determination of mass properties are difficult by analytical formulae or closed form solutions. Therefore, experimental procedures are optimal rather than the analytical model. This study deals with the fabrication of compound pendulum, experimentation to determine the radius of gyration, mass moment of inertia and acceleration due to gravity at Ibri. [ABSTRACT FROM AUTHOR]

Vibration is the periodic motion due to elastic property of body. Anything has mass and elasticity can vibrate but a rigid body cannot vibrate. Oscillation is also periodic motion as restoring force is due to weight of the body. Even rigid body can oscillate. A wide range of applications found in IC engines, Jet engines, Electro-mechanical drives, reciprocating compressors, etc. Excessive vibration causes sudden structural failure which leads to catastrophe or major accidents. Hence, it is necessary to evaluate natural frequency of vibration to avoid failure of the system due to resonance. The present study aims to determine the natural frequency of torsional oscillation experimentally in un-damped and damped condition. The materials used in the present study are Steel and Brass. For each of the material, the time required for 20 oscillations were noted with and without damper. The steel found better torsional characteristics than brass in un-damped condition as steel has better elastic properties. The effect of mass moment of inertia, length and diameter of the rod on torsional oscillations were studied. Moreover, the damping characteristics of oil was studied and found that higher the damping factor if the amplitude reduction factor is high. [ABSTRACT FROM AUTHOR]

A spatial mechanism commonly employed for the control of angular motion of a body is called Gyroscope. The resistance to change in the direction of rotational axis is called the gyroscopic effect. The torque or turning moment, that opposes any change of the inclination of the axis of rotation of a gyroscope, is called gyroscopic couple. Or in other words, whenever the axis of a rotating body is caused to change direction, a couple is required, called as gyroscopic couple. The reaction to this couple is experienced in aircraft, marine and car engines when changing direction and is also employed in navigating systems. In the present study, a motorized gyroscope apparatus is used to evaluate the active and reactive gyroscopic couple. The apparatus is made up of a brass gyroscope flywheel mounted in a cradle which allows the flywheel to pivot in the x, y and z directions. When the gyroscopic couple is equal to the couple applied by the counterbalance weight; the arm of the gyroscope will run in a horizontally. When the arm of the gyroscope is horizontal, the speed of precession and the spin speed have to be recorded. Knowing the mass properties of the flywheel in addition to these speeds, the gyroscopic couple can be estimated experimentally. From the mass of counterbalance weight and the radius of rotation, the theoretical couple that can be produced by the apparatus can be evaluated. Reasonably good agreement was observed between test and theoretical results. [ABSTRACT FROM AUTHOR]

Pressure vessels are employed as storage tanks because they can store fluids at pressures that are significantly higher or lower than the surrounding ambient condition. Pressure vessels can be of any shape, however spherical and cylindrical shapes are usually employed for domestic to space applications. A common design in cylindrical pressure vessel is a cylinder with end caps frequently of hemispherical in shape. Damaged pressure vessels may fail, rupture, or at the very least leak. Poisonings, fires and explosion dangers are among the possible health and safety risks posed by leaking storage containers. Burst failures, which can be significantly more disastrous, can seriously harm both people and property. As a result, it is crucial for figuring out their operational difficulties. Thin cylindrical type 1 pressure vessel for hydrogen storage is considered in the present study. The stresses induced in thin cylinders due to internal pressure are circumferential (also known as hoop stress) and longitudinal stresses. Since, the magnitude of hoop stress is twice the value of longitudinal stress, the pressure vessel has to be designed for hoop stress. A numerical and /or mathematical model is required to analyse the pressure vessels, as experimental evaluation of induced stresses is an expensive procedure. Since Finite Element Analysis (FEA) is the most accepted numerical tool to design pressure vessels, the ANSYS R15 software has been used to evaluate the longitudinal and circumferential stresses and found good in agreement with analytical results. [ABSTRACT FROM AUTHOR]