As the need for speed and precision in modern manufacturing technologies increases, linear motors are attracting considerable research attention. Heat management and thermal deformation associated with linear motors comprise a major concern tied to the demand for machining accuracy. Here we describe a three-dimensional finite-element simulation analysis method that utilizes a three-phase linear synchronous motor for thermally characterizing a feed-driven system. We also present results from simulations and experiments aimed at verifying system thermal time constants and temperature distributions. These results demonstrate that the proposed analytical method is capable of making accurate and useful predictions of temperature and thermal behavior distributions for linear motors in terms of conventional heat generation in various transient and steady-state phases. It is our hope that these results will support future efforts to design modern feed-driven systems equipped with linear motors

To study the performance and estimate the oscillating bearing loads of a twin screw air compressor, a theoretical model is proposed in this paper. Based on the model, a computer simulation program is developed and effects of different design parameters such as rotor profile, geometric clearance, oil injected position, oil temperature, oil flow rate and other operational conditions are investigated. Output variables such as bearing loads, specific power, compression efficiency, volumetric efficiency, discharge temperature are obtained. Some of the results are then compared with experimentally measured data, and good agreements are found between the simulation results and the measured data.

A theoretical model is proposed in this paper in order to study the performance of oil-less and oil-injected twin screw air compressors. Based on this model, a computer simulation program is developed and the effects of different design parameters including rotor profile, geometric clearance, oil-injected angle, oil temperature, oil flow rate, built-in volume ratio and other operation conditions on the performance of twin screw air compressors are investigated. The simulation program gives us output variables such as specific power, compression ratio, compression efficiency, volumetric efficiency, and discharge temperature. Some of the above results are then compared with experimentally measured data and good agreement is found between the simulation results and the measured data.