State-of-the-art hydraulic hose and piping systems employ integral sensor nodes for structural health monitoring to avoid catastrophic failures. Energy harvesting in hydraulic systems could enable self-powered wireless sensor nodes for applications such as energy-autonomous structural health monitoring and prognosis. Hydraulic systems inherently have a high energy intensity associated with the mean pressure and flow. Accompanying the mean pressure is the dynamic pressure ripple, which is caused by the action of pumps and actuators. Pressure ripple is a deterministic source with a periodic time-domain behavior conducive to energy harvesting. An energy harvester prototype was designed for generating low-power electricity from pressure ripples. The prototype employed an axially-poled off-the-shelf piezoelectric stack. A housing isolated the stack from the hydraulic fluid while maintaining a mechanical coupling allowing for dynamic-pressure-induced deflection of the stack. The prototype exhibited an off-resonance energy harvesting problem since the fundamental resonance of the piezoelectric stack was much higher than the frequency content of the pressure ripple. The prototype was designed to provide a suitable power output for powering sensors with a maximum output of 1.2 mW. This work also presents electromechanical model simulations and experimental characterization of the piezoelectric power output from the pressure ripple in terms of the force transmitted into the harvester.

State-of-the-art hydraulic hose and piping systems employ integral sensor nodes for structural health monitoring in order to avoid catastrophic failures. These systems lend themselves to energy harvesting for powering sensor nodes. The foremost reason is that the power intensity of hydraulic systems is orders of magnitude higher than typical energy harvesting sources considered to date, such as wind turbulence, water flow, or vibrations of civil structures. Hydraulic systems inherently have a high energy intensity associated with the mean pressure and flow. Accompanying the mean pressure is what is termed dynamic pressure ripple caused by the action of pumps and actuators. Pressure ripple is conducive to energy harvesting as it is a deterministic source with an almost periodic time domain behavior. Pressure ripple generally increases in magnitude with the mean pressure of the system, which in turn increases the power that can be harvested. The harvested energy in hydraulic systems could enable self-powered wireless sensor nodes for applications such as energy-autonomous structural health monitoring and prognosis. An energy harvester prototype was designed for generating low-power electricity from dynamic pressure ripples. The prototype employed an axially-poled off-the-shelf piezoelectric stack. A housing isolated the stack from the hydraulic fluid while maintaining mechanical coupling to the system to allow for dynamic pressure induced deflection of the stack. The system exhibits an attractive off-resonance energy harvesting problem since the fundamental resonance of the piezoelectric stack is much higher than the frequency content of ripple. Although the energy harvester is not excited at resonance, the high energy intensity of the ripple results in significant electrical power output. The prototype provided a maximum output of 1.2 mW at 120Ω. With these results, it is clear that the energy harvester provides non-negligible power output suitable for powering sensors and other low power components. This work also presents electromechanical model simulations for predicting the piezoelectric power output in terms of the force transmitted from the pressure ripple as well as experimental characterization of the power output as a function of the force from the ripple.

A hydraulic pressure energy harvester (HPEH) device, which utilizes a housing to isolate a piezoelectric stack from the hydraulic fluid via a mechanical interface, generates power by converting the dynamic pressure within the system into electricity. Prior work developed an HPEH device capable of generating 2187 microWatts from an 85 kPa pressure ripple amplitude using a 1387 mm3 stack. A new generation of HPEH produced 157 microWatts at the test conditions of 18 MPa static pressure and 394 kPa root-mean-square pressure amplitude using a 50 mm3 stack, thus increasing the power produced per volume of piezoelectric stack principally due to the higher dynamic pressure input. The stack and housing design implemented on this new prototype device yield a compact, high-pressure hydraulic pressure energy harvester designed to withstand 35 MPa. The device, which is less than a 2.54 cm in length as compared to a 5.3 cm length of a previous HPEH, was statically tested up to 21.9 MPa and dynamically tested up to 19 MPa with 400 kPa root-mean-square dynamic pressure amplitude. An inductor was included in the load circuit in parallel with the stack and the load resistance to increase the power output of the device. A previously developed electromechanical power output model for this device that predicts the power output given the dynamic pressure ripple amplitude is compared to the power results. The power extracted from this device would be sufficient to meet the proposed applications of the device, which is to power sensor nodes in hydraulic systems.

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Environmental pollution is one of the major concerns of all the environment related departments. Industrialization is at peak, releasing billions of tones of wastes & byproducts every day, thereby producing a great threat to the existing living creatures of the universe. So it is the dire need of the hour to tackle with such problems, in a technical manner so that the hazards of these wastes will be reduced to minimum extent. As far Blast furnace slag & Cast Iron Chips are concerned they were considered to be as waste materials & were thrown unused. In this present research work we are going to bring such said wastes in, this will not only increase the practical utility of these products but also will make the concrete mixes economical & will reduce the threat of environment by being polluted by such wastes. In the present study firstly we will fabricate Mix A i.e., M-20 grade of concrete, with 0.5 water cement ratio & secondly we will prepare concrete mixes first by partially replacing the fine aggregates with cast iron chips, by weight. The range of replacement of fine aggregates varies as 10%, 20% & 30% respectively & such mixes are named as Mix B, Mix C & Mix D respectively. In the second context we are replacing cement with Blast Furnace Slag, but the percentage of Cast Iron Chips remains the same i.e., 30%. Here the levels of replacement will remain the same as in previous case i.e., 10%, 20% & 30%. So Mix E is composed of 30% by weight of Cast Iron Chips (replacement of sand by weight =30% with Cast Iron Chips), 10% by weight of Blast Furnace Slag & other ingredients of concrete. Mix F is composed of 30% by weight of Cast Iron Chips (replacement of sand by weight =30% with Cast Iron Chips), 20% by weight of Blast Furnace Slag, with 20% replacement of cement & rest of the constituents remaining the same. Mix G will be the composition of 30% by weight of Cast Iron Chips (replacement of sand by weight = 30% with Cast Iron Chips), 30% by weight of Blast Furnace Slag, replacing 30% of cement in the mix. The results recommend the use of Cast Iron Chips in concrete instead of sand & use of Blast Furnace Slag instead of cement as well , up to certain level of replacement& improves the compressive strength of concrete mixes fabricated by bringing such wastes in use.