In this study, we investigated the squeeze flow of an upper convected Maxwell fluid between two rigid disks or spheres. It has been proved that the velocity field of the Maxwell squeeze flow between two disks is similar to Newtonian at low Deborah numbers. Based on the Newtonian fluid velocity field, we analyze the pressure distribution between two parallel disks and develop a theoretical model of normal squeeze force. We also use the same method to analyze the interaction between two nearly contacting, arbitrary rigid spheres. We obtained the analytical expression of the pressure distribution and normal squeeze force, which can be implemented into the contact model for the discrete element simulation of a wet particle system with the Maxwell fluid.

In this study, we investigate the squeeze flow behavior of an upper-convected Maxwell fluid between a sphere and a plate. Based on the Newtonian fluid velocity field, we use the perturbation method to derive analytical expressions for the pressure distribution and normal squeeze force of the sphere–plate squeeze flow, which can be implemented into the contact model for the discrete element simulation of a wet particle system with a Maxwell fluid. Additionally, the sphere–plate case investigated in this paper can be easily transformed into both the plate–plate and sphere–sphere cases, forming a set of complete contact force models with these two cases, thus offering a wider applicability.

Existing evidence indicates that endoscopic retrograde biliary drainage (ERBD), often combined with sphincterotomy, leads to enterobiliary reflux (EBR), which is a major cause of stent occlusion. A...

Precise measurement or simulation of particle collisions in liquids typically requires prohibitively high spatiotemporal resolution. This study employs lubrication theory to develop a reconstruction technique for the collision parameters and process of spherical particles in liquids with known properties. Time series of collision behaviors under varying parameters are first obtained through direct numerical simulation level adaptive refinement fully resolved numerical simulations. The sequence to be enhanced is then derived through subsampling and noise addition. A simplified relationship is developed using lubrication theory to evaluate key parameters with constrained uncertainties, enabling the recovery of high-resolution temporal processes and the extraction of critical parameters such as the equivalent recovery coefficient and collision time. The approach is successfully applied to enhance experimental data of spherical inertial measurement unit particle collisions, significantly improving the accuracy of collision event measurements. This method shows promise for enhancing low-resolution experimental or numerical simulation data in similar collision problems.