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This article investigates the under-explored potential of utilizing a thin stainless-steel diaphragm coupled with a quartz tuning fork sensor for liquid depth measurements. The focus is on monitoring molten salt fluid levels in nuclear reactors and concentrated solar power systems. Addressing a literature gap, the research explores cantilever-type configurations of a double-ended quartz tuning fork resonator, with a no-load resonance frequency of 17.37 kHz, on thin stainless-steel diaphragms for fluid depth measurement at room temperature. As the fluid depth increases, hydro-static pressure acting on a 20 μ m diaphragm causes deflection, bending a tuning fork. The resulting change in resonance frequency correlates with fluid depth. Experimental setups assess the tuning fork's sensitivity to strain and bending, revealing strain sensitivity of 7.83 Hz/ μ strain (450.78 ppm/ μ strain) and bending sensitivity of 0.09 Hz/ μ m (5.18 ppm/ μ m). The pressure sensor assembly, tested in a water tank, exhibits a sensitivity of − 0.28 Hz/mm (− 16.12 ppm/mm) in a single cantilever-type configuration. Despite a limited linear range, it effectively measures water depth changes as small as 0.7 mm. Exploring a double cantilever-type configuration yields a sensitivity of 0.07 Hz/mm (4.03 ppm/mm) with a broader linear range. The article discusses the reasons for opposite sensitivity and highlights the advantages of each configuration. Beyond molten salt level monitoring, the technology's applications may extend to fluid depth and pressure measurements in industrial and domestic settings. [ABSTRACT FROM AUTHOR]

Hydroacoustic projectors are useful for generating low frequency sounds in water. Existing works on hydroacoustic projectors require two significant enhancements, especially for designers. First, we need to understand the influence of important projector design parameters on its performance. Such insights can be very useful in developing a compact and efficient projector. Second, there is a need for an integrated model of the projector based on easily available and user-friendly numerical tools which do not require development of complex customised mathematical analogs of projector components. The present work addresses both such needs. Towards these goals, an experimentally validated, easy-to-build projector model was developed and used to conduct design sensitivity studies. We show that reductions in pipe compliance and air content in oil, and an increase in orifice discharge coefficient can yield remarkable improvements in projector’s SPL. We also show that reductions in pipe length and cylinder diameter cause moderate improvements in performance in mass and stiffness controlled regions, respectively. In contrast, the projector performance is insensitive to changes in pistonic mass, cylinder length, and diaphragm stiffness. Finally, we report that while pipe compliance and air content in oil can sharply alter system resonance, the effects of changes in pipe length and pistonic mass on it are moderate in nature.

Knowledge of internal ballistic pressure and projectile velocity is required to ensure gun safety, reliability, calculation of its range, and evaluation of ammunition. However, existing methods for determining the same are either overly complex, costly or have limitations in their applicability. In this work, the authors address this need by proposing a reliable, simple, cheap, and non-destructive method for determining in-bore pressure, projectile velocity, and acceleration profile using strain measurements. Data from strain gauges were used to detect the projectile's arrival time at different locations in the barrel and computed projectile velocity and acceleration as a function of projectile position. Finally, acceleration data was used to calculate the pressure behind the projectile. Results were verified using alternative experimental and simulation techniques on two different barrels with different ammunition. It was found that the proposed method works well and thus can be reliably used in similar applications elsewhere. [ABSTRACT FROM AUTHOR]