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This paper presents some results of simulation using ANSYS CFX software in design air spindle which has the structure in the form of orifice and grooves to ensure uniform pressure distribution and avoiding air hammer; it is also easy to manufacture and reduces costs. The results of simulation are good in investigating operation of air-spindle which is changed some parameters to find the optimal working mode for the air spindle with speed in the range of 5000–20,000 rpm.

In this paper, we have studied the effect of variable-angle grooves and baffles on the mixing efficiency of the micromixer. In order to explore the influence on the micromixer with different types of grooves and baffles, we designed grooves and baffles with different geometric parameters and placed them in T-channels to interfere with fluid flow. We studied VAM30^∘ (variable-angle grooves and baffles micromixer with an angle of 30^∘) directions and distributions as well as their different groove depths and baffle heights affect the mixing performance. We tried to divide the grooves and baffles into five groups, and discussed the effects of staggered depth and height on mixing efficiency. The mixing efficiencies of micromixer in the Re (Reynolds number) range of 0.1–100 were calculated, and the fluid flow in the microchannel was analyzed. The simulation results show that VAM30^∘ is more favorable for solution mixing. The mixing efficiency of the micromixer could reach 98.9% with the change of different geometric parameters. This is because when the structure changes, the flow state of the fluid is improved, which is conducive to lengthening the residence time of the fluid in the channel. With the increase of Re, it is also conducive to enhancing the chaotic convection and improving the mixing efficiency.

This study aims to analyze the surface pattern created on a shape memory polymer (SMP; thermoset polystyrene) after indentation by a spherical indenter, polishing off the top surface and recovery through the shape memory effect (SME) using the finite element method (FEM) and other computational techniques. Depending on how to polish, three different types of patterns are generated, namely the lens-type protrusion, flat-top protrusion and groove. The actual dimensions of the surface patterns are determined by the polishing depth and the coefficient of friction during indentation. The influence of the latter can be fixed if the coefficient of friction is over a certain value. All the lengths in this study are normalized with the respective indent depth. Hence the results can be scaled. The trends obtained here should be applicable to other shape memory polymers.

In this study, through numerical simulation, an effort has been made to acknowledge the efficiency of machining Titanium grade 23 under vibration assistance with textured cutting tools. Dry turning experiments with commercially available carbide inserts without texturing were carried out without vibration assistance. Cutting forces ($F$${}_x$, $F$${}_y$, $F$${}_z$) were observed during experimentation, which were further validated using DEFORM 3D. The forces were validated using DEFORM 3D. Closer to the cutting edge, dimple type 1, dimple type 2, horizontal, and vertical patterns were made on cutting inserts using SOLIDWORKS software. A numerical model based on experimentation was developed employing DEFORM 3D software for conventional and vibration-assisted turning. Cutting forces ($F$${}_x$, $F$${}_y$, $F$${}_z$), cutting temperature, tool wear, and the mechanism of chip formation were also explored through FEM investigation. Micro-textured inserts were found to be enhancing machinability. Machining with vibration assistance also improved machinability. The study found that textured tools improved machinability in conventional and vibration-assisted machining modes. The effect of textured tools on machinability improved with vibration-assisted machining. The numerical analysis revealed that dimple type 1 and vertical grooved tool improved the machinability of Titanium grade 23.

Anterior dislocation of the ulnar nerve is occasionally encountered after simple decompression of the nerve for treatment of cubital tunnel syndrome. The purpose of this study was to determine whether the incidence of dislocation of the nerve following simple decompression of the nerve is correlated with the patient's preoperative characteristics and/or elbow morphology. We studied 51 patients with cubital tunnel syndrome who underwent surgery at our institution. Intraoperatively, we simulated dislocation of the nerve after simple decompression by flexing the elbow after releasing the nerve in each patient. Univariate and multiple logistic regression analysis showed that young age and a small ulnar nerve groove angle are positively correlated with dislocation of the nerve. Our results suggest that patients who are young and/or have a sharply angled ulnar nerve groove identified radiographically have a high probability of experiencing anterior dislocation of the ulnar nerve after simple decompression.