Electrorheological and magnetorheological fluids in blast resistant design applications

The performance of electrorheological (ER) and magnetorheological (MR) fluids under impulsively-applied loads is investigated. The ER fluid device, which is operating in the squeeze flow mode, is tested with four different ER fluids, while the MR fluid device is a commercially available shock absorber in which the flow resistance of the fluid is controlled by a small electromagnetic element. Both devices were tested in an experimental rig, capable of providing fast loading that represents the typical loading of an explosive shock in air or the typical loading of a hydrocarbon type explosion. These devices were seen to exhibit sufficient field-induced damping forces when subjected to various mechanical and electrical inputs and hence, they are capable of providing adaptable fixing characteristics for blast resistant and structural members such as blast walls on offshore platforms. In addition, the performance of the ER fluid device under fast loading could be predicted by a theoretical model based on the assumption of a bi-viscous fluid characteristic, and was found to compare very well with that acquired experimentally.