Objectives  This paper investigates the flow field distribution inside a working viscous fluid damper (VFD) , and the sensitivity of the hole radius, hole length, number of holes and piston diameter to the damping coefficient and velocity index.

  Methods  Parameter design schemes are obtained through orthogonal design, and a FLUENT flow field simulation is applied to study the flow field distribution, and calculate the impact degree of structural parameter on the damping coefficient and velocity index of each scheme.

  Results  The results show that the internal flow field distribution basically conforms to the regular distribution of laminar flow in parallel flat plates and tubes, the impact degree of of each factor on the damping coefficient and the velocity is obtained in descending order, i.e. hole radius>piston diameter> number of holes>hole length, and hole radius>number of holes>hole length>piston diameter.

  Conclusions  The combination of orthogonal design and FLUENT flow field simulation can minimize the design scheme, shorten the design cycle, and reduce experimental cost, giving it great significance for practical engineering applications.