Shock absorbing liquid

Davies, H., Holford, K., Assoune, A., Ttioidier, B., Courtney, B. (2009). Pedestrian protection using a shock absorbing liquid (SALi) based bumper system. In 21st International Technical Conference on the Enhanced Safety of Vehicles (ESV 2009) (No. 09-0027). 

Shock absorbing liquid (SALi) Technology -based cushions consist of small, compressible elastic capsules blended with an incompressible matrix fluid for protection from violent impacts, crash, vibrations and shock waves. It is suggested that the cushions offer four damage mitigation mechanisms in the impact energy absorption process ... 

Courtney WA (1998), Preliminary investigations into the mechanical properties and potential applications of a novel shock absorbing liquid, MPhU Thesis, Manchester School of Engineering, University of Manchester. 

Elame arresters for chemical process equipment and flammable liquid containers have been available for over 120 years. A US patent was issued as early as 1878 for a spark-arrester (Allonas 1878), while another spark-arrester was patented in 1880 (Stewart 1880). Numerous US patents have been issued for various designs of flame arresters, with one as recent as 1995 (Ronssakis and Brooker 1995). In Germany, patents were issued in 1929 and 1939 for flame arresters that contained shock absorber internals upstream of the flame arrester elements. This innovation made them suitable as detonation arresters (Wanben 1999). 

Stossel, m. pestle stamper, rammer tappet, stossempfindlich, a. sensitive to shock, stossen, v.t. push, thrust, hit, knock, ram pound, bray, pulverize join slot. — v.t. thrust, dash, hit (at, against, or upon) (of boiling liquids) bump, knock recoil. Stosser, m. pestle rammer, pounder, knocker. Stossfitnger, m. pressure equalizer, shock absorber. 

It is convenient to use a simple weightless Hookean, or ideal, elastic spring with a modulus G and a simple Newtonian (fluid) dashpot or shock absorber having a liquid with a viscosity of 17 as models to demonstrate the deformation of an elastic solid and an ideal liquid, respectively. The stress-strain curves for these models are shown in Figure 14.1. 

Models are used to describe the behavior of materials. The fluid or liquid part of the behavior is described in terms of a Newtonian dashpot or shock absorber, while the elastic or solid part of the behavior is described in terms of a Hookean or ideal elastic spring. The Hookean spring represents bond flexing, while the Newtonian dashpot represents chain and local segmental movement. 

The earlier brake fluids of such materials as castor oil, glycerols, and alcohols could not meet the requirements of wide temperature range if the liquid was low enough in viscosity at the low temperature, it was too thin at the high for the pumps to operate motors at speed. If high enough in viscosity at the upper temperature, it was cheese at the low. Operators found that out in Arctic maneuvers, by way of broken shock absorber arms, burst brake and hydraulic system tubing, and sheared pump shafts. 

Good compressibility of silicone liquids (up to 14%) is essential for their use as shock absorbers. In particular, they are used for filling the unions of cylinders and pipelines, for shock absorption for airplace chassis, for sheet metal dyes, for artilleiy weapons, etc. Apart from absorbing shocks, these liquids damp any ensuing oscillations, i.e. act as damping agents. 

Abstract Grease lubrication is a complex mixture of science and engineering, requires an interdisciplinary approach, and is applied to the majority of bearings worldwide. Grease can be more than a lubricant it is often expected to perform as a seal, corrosion inhibitor, shock absorber and a noise suppressant. It is a viscoelastic plastic solid, therefore, a liquid or solid, dependent upon the applied physical conditions of stress and/or temperature, with a yield value, ao- It has a coarse structure of filaments within a matrix. The suitability of flow properties of a grease for an application is best determined using a controlled stress rheometer for the frequency response of parameters such as yield, a, complex shear modulus, G phase angle, 5, and the complex viscosity, rj. ... 

DISPOSAL AND STORAGE METHODS absorb liquid in sand or inert absorbent, and place in a secured, sanitary landfill store in a cool dry location use only with adequate ventilation storage should be in a separate building keep containers tightly closed bond and ground containers to prevent build-up of electrostatic charges when transferring liquid separate from acids keep away from any area where the fire hazard may be acute do not expose to shock or friction. 

Steel bracket, which is fixed by anchor bolts to the top surface of abutment, is utilized as an unseating-prevention device. A shock absorbing chain connected between the steel bracket at bottom of girder and that of vertical front wall of concrete abutment is also adopted in order to avoid the bridge falling. Injected liquid epoxy resin is effective to fix the anchor bolts in horizontally bored hole. 

Step 6. Fix a flow rate in every recycle loop and control vapor and liquid inventories (vessel pressures and levels). Process unit inventories, such as liquid holdups and vessel pressures (measures of vapor holdups), are relatively easy to control. While vessel holdups are usually non-self-regulating (Guideline 1), the dynamic performance of their controllers is less important. In fact, level controllers are usually detuned to allow the vessel accumulations to dampen disturbances in the same way that shock absorbers cushion... 

The values of v in the above equation are the equilibrium values after an infinite pressing time. There are kinetics involved here too in that the deformation of the cake due to a mechanical stress is not instantaneous but dampened by the necessary permeation of the liquid out of the cake. Baluais et al. considered a rheological model for this in analogy with the action of a shock absorber in parallel with one spring and in series with another. 

An elastic solid responds to stress like a spring. It responds instantly by stretching in proportion to the applied stress, and recovers completely when the stress is removed. A viscous liquid, on the other hand, responds like a dashpot or shock absorber. It deforms with a velocity that is proportional to the stress and does not recover when the force is removed. A viscoelastic material combines the two behaviors and can be modeled as a spring and dashpot in series or parallel as shown in Figure 9.9. Newtonian fluids have pure... 

A filtered solution, prepared by heating mercuric oxide with a slight excess of perchloric acid, after standing for several months precipitated a little unidentified white solid. This (but not the supernatant liquid) was very shock sensitive, and detonated as it was being rinsed out with water. (Traces of a volatile amine may have been absorbed into the acid liquor to give an amminemercury perchlorate, expected to be explosive). 

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