Hydrostatic equilibrium

About: Hydrostatic equilibrium is a research topic. Over the lifetime, 2451 publications have been published within this topic receiving 62172 citations.

Measurement of small values of hydrostatic pressure difference / Pomiar małych wartości różnicy ciśnień hydrostatycznych

Abstract: In order to describe the fluid flow through the porous centre, made of identical spheres, it is necessary to know the pressure, but in fact – the pressure distribution. For the flows in the range that was traditionally called laminar flow (i. e. for Reynolds numbers (Bear, 1988; Duckworth, 1983; Troskolanski, 1957) from the range 0,01 to 3) it is virtually impossible with the use of the tools directly available on the market. Therefore, many scientists who explore this problem have concentrated only on the research of the velocity distribution of the medium that penetrates the intended centre (Bear, 1988) or pressure distribution at high hydraulic gradients (Trzaska & Broda, 1991, 2000; Trzaska et al., 2005). It may result from the inaccessibility to the measurement methods that provide measurement of very low hydrostatic pressures, such as pressure resulting from the weight of liquid located in the gravitational field (Duckworth, 1983; Troskolanski, 1957). The pressure value c. 10 Pa (Troskolanski, 1957) can be generated even by 1 mm height difference between the two levels of the free water surface, which in fact constitutes the definition of gauging tools of today measuring the level of the hydrostatic pressure. Authors proposed a method of hydrostatic pressure measurement and devised a gauging tool. Then a series of tests was conducted aiming at establishing what is the influence of various factors, such as temperature, atmospheric pressure, velocity of measurement completion, etc. on the accuracy and method of measurements. A method for considerable reduction of hysteresis that occurs during measurement was also devised. The method of measurement of small hydrostatic difference measurements allows for the accuracy of measurement of up to 0.5 Pa. Measurement results can be improved successfully by one order of magnitude, which for sure would entail necessary temperature stabilization of the tool. It will be more difficult though to compensate the influence of atmospheric pressure on the measurement process.

Hydrostatic seismic sensor

Abstract: A hydrostatic seismic sensor including a sensing mass suspended on a defoble reservoir containing a sensing fluid and a differential pressure transducer to measure the pressure in the reservoir.

A Study on Creep-Fatigue Interaction of Polycrystalline Metal at Elevated Temperature : Specially, on the Effect of Hydrostatic Pressure on Crack Behavior.

Abstract: Sheet test specimen of commercial pure copper was used and tests on three types of stress waves were performed under atmospheric and hydrostatic pressures of 1000kg/cm2 at 270°C. From the present experiments the following were concluded. At the same stress wave, time to rupture of the material under hydrostatic pressure was remarkably longer than that in atmosphere. In this connection, slower crack initiation and propagation rate were observed under hydrostatic pressure as compared to atmospheric pressure. From the calculation of both fatigue damage φf of the material and creep damage φc in the tests of fatigue with hold-time, the value of commulative damage, φc+φf, is larger than unity under both hydrostatic and atmospheric pressures. The fatigue damage of the material is predominant under hydrostatic pressure but the creep damage of the material is influential under atmospheric pressure.