Preparation of diester-based ferrofluid and applied research in sealing

To improve the sealing performance of ferrofluid, a Fe3O4 magnetic nanoparticles with different coating times was synthesized by the chemical co-precipitation method, and the performance of diester-based Fe3O4 ferrofluid was investigated and characterized. A convergent ferrofluid seal (CFFS) device was designed and the prepared ferrofluid was applied to it. The influence of important factors such as seal clearance and pole teeth of CFFS on the pressure capability of the CFFS are investigated using simulations and experiments. The results show that the prepared magnetization intensity of the ferrofluid is 29.5 kA/m. The simulation and experimental results of the CFFS agree well, and its performance is 3.3 times that of the ordinary ferrofluid seal.