Lead zirconate titanate (PZT)/Ni cantilevers have been developed using the pulsed laser deposition technique for harnessing magnetic as well as mechanical energy. High voltage (1.2 mV, 1.8 mV, and 8.5 mV) and power density (1100, 2400, and 3600 mW/m3) were generated across the PZT/Ni cantilevers (in 3–3 mode) having PZT thin films deposited at 100 mTorr, 200 mTorr, and 300 mTorr oxygen pressures, respectively, at their respective resonance frequencies with 0.5 g acceleration. Maximum power response (3600 mW/m3) was observed at a load resistance of 100 kΩ for the cantilever having PZT film deposited at 300 mTorr oxygen pressure, which is manifested to the efficient ferroelectric and ferromagnetic properties of PZT/Ni system. The power generated from the PZT/Ni cantilever was further enhanced to 18 700 mW/m3 by superimposing magnetic energy with mechanical vibrations. These results are extremely promising for the realization of an efficient energy harvester utilizing both magnetic and mechanical energy.

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Globe valves are one of the oldest valve types used for throttling applications for all sizes due to better controllability and range. One of the major limitations associated with the use of globe valves in liquid application is cavitation. It takes place both in part open and in fully open conditions due to varied reasons. There are different designs of globe valves available but for control valve applications, cage and plug designs are widely employed. Cage and plug design consists of body, valve cage, plug and an actuating mechanism. Actuating mechanism is connected to the valve plug (moving part), through valve shaft. There are many investigations reported about the flow visualization and numerical simulation of normal type globe valves. But study on valves with cage and plug design are not tried in detail. The objective of the present work is to provide a comprehensive study of flow through a globe valve with cage and plug design with emphasis on cavitation. Cavitation reduction is achieved by breaking the flow in the form of more than one liquid jets, there by increasing the turbulence in the valve flow path. This ensures the local static pressure not going below vapour pressure. Experimental studies were done in the water test facility with an operating pressure of 1.6 MPa and flow rate of 0.05 m 3 /s. In the study, total area of opening of the valve and the valve stroke were kept constant.

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