Hydrostatic equilibrium

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

Opposite hydrostatic forming

Abstract: PURPOSE:To increase the compression force to be applied to the circumferential edge part of a punch in a blank even when the axial compression force to be applied to the punch is small because the hydrostatic pressure higher than the hydrostatic pressure to be generated in the punch side hydrostatic pressure chamber is generated in the flange side hydrostatic pressure chamber. CONSTITUTION:In executing the deep drawing by pushing the blank A to be held on the surface of a die body 1 through a blank holder 4 into a hydrostatic pressure chamber 2 formed in the die body 1 by using a punch 3, the prescribed part of the hydrostatic pressure chamber in the outer circumferential wall part of the punch of the blank A is sealed by a seal material 5 when the blank A is pushed into the hydrostatic pressure chamber 2. The hydrostatic pressure higher than the hydrostatic pressure to be generated in the punch side hydrostatic pressure chamber 2c close to the punch tip is generated in the flange side hydrostatic pressure chamber 2b closer to the flange than to this sealed part.

Comparative Study of Velocities Under Hydrostatic And Non-hydrostatic Stress In Sands

Abstract: In this paper, we compare Vp measured under hydrostatic and non-hydrostatic stress conditions in a sand. We describe how we apply isotropic stress using a polyaxial apparatus. We examine velocities in three perpendicular directions as function of stress and find that Vp under hydrostatic pressure is higher than Vp measured under nonhydrostatic isotropic stress. Furthermore, we observe that velocity anisotropy revealed the intrinsic anisotropy in the sands.

The Three Hundred project: A Machine Learning method to infer clusters of galaxies mass radial profiles from mock Sunyaev-Zel’dovich maps

Abstract: We develop a machine learning algorithm to infer the 3D cumulative radial profiles of total and gas mass in galaxy clusters from thermal Sunyaev-Zel’dovich effect maps. We generate around 73,000 mock images along various lines of sight using 2,522 simulated clusters from the The Three Hundred project at redshift z < 0.12 and train a model that combines an autoencoder and a random forest. Without making any prior assumptions about the hydrostatic equilibrium of the clusters, the model is capable of reconstructing the total mass profile as well as the gas mass profile, which is responsible for the SZ effect. We show that the recovered profiles are unbiased with a scatter of about $10\%$, slightly increasing towards the core and the outskirts of the cluster. We selected clusters in the mass range of 1013.5 ≤ M200/( h−1M⊙) ≤ 1015.5, spanning different dynamical states, from relaxed to disturbed halos. We verify that both the accuracy and precision of this method show a slight dependence on the dynamical state, but not on the cluster mass. To further verify the consistency of our model, we fit the inferred total mass profiles with an NFW model and contrast the concentration values with those of the true profiles. We note that the inferred profiles are unbiased for higher concentration values, reproducing a trustworthy mass-concentration relation. The comparison with a widely used mass estimation technique, such as hydrostatic equilibrium, demonstrates that our method recovers the total mass that is not biased by non-thermal motions of the gas.