The normal stress of an electrorheological fluid in compression mode
Abstract
This work studied the normal stress of an ER fluid in compression mode through both experiment and simulation. The TiO2 based ER fluid was used to test the normal stress under different DC voltages and compressive speeds. The normal stress reached about tens of kPa and was affected by the applied voltage and compressive parameters. Then, a simulation model was presented to investigate the influencing factors on the normal stress. The computational normal stresses agreed well with the experimental results. Typically, the shear action was also found to be very important for the normal stress during the compression. When the shear rate is small, the shear action showed little effect on normal stress. When the shear rate exceeded a critical value, the normal stress oscillated within a certain range. At last, an ideal 2D simulation was conducted to investigate the relation between the mechanical property and the structure transformation.