Abstract: Using the numerical and experimental methods, this paper discusses some primary studies on the vibration and cooling performances of the piezoelectric cooling fan with the rectangular blade. When the fan works at its natural frequency, the vibrating displacement is largest and the cooling performance is best. Due to the vibration behavior, the cooling performance is affected by the geometry, material property, and working frequency of the piezoelectric cooling fan.
Abstract: This paper investigates the thermo-electric effects
around the crack and notch tips under the electric current load. The
research methods include the finite element analysis and thermal
imaging experiment. The finite element solutions show that the electric
current density field concentrates at the crack tip. Due to the Joule
heating, this electric concentration causes the hot spot at the tip zone.
From numerical and experimental results, this hot spot is identified.
The temperature of the hot spot is affected by the electric load,
operation time and geometry of the sample.
Abstract: The numerical simulation of the crack welding process is reported in this paper. The thermo-electro-structural coupled-field finite element analysis is adopted to investigate the welding process of crack surfaces. In the simulation, the pressure-dependent and temperature-dependent electrical contact conditions are considered. From the results, the crack surfaces can melt and weld together under the compressive load and electric current. The contact pressure effect must be considered in the finite element analysis to obtain more practical results.
Abstract: The finite element analysis is adopted in this primary study. Using the Tsai-Wu criterion and delamination criterion, the stacking sequence [45/04/-454/904]s is the final optimal design for the wheelchair frame. On the contrary, the uni-directional laminates, i.e. [9013]s, [4513]s and [-4513]s, are bad designs due to the higher failure indexes.
Abstract: This paper discusses some notes on the vibration design for the piezoelectric cooling fan. After reviewing the fundamental formulas of the cantilever Euler beam, it is not easy to find the optimal design of the piezoelectric fan. The experiments also show the complicated results of the vibration behavior and air flow.
Abstract: Using the finite element analyses, this paper discusses the effects of temperature-dependent material properties on the stress and temperature fields in a cracked metal plate under the electric current load. The practical and complicated results are obtained when the temperature-dependent material properties are adopted in the analysis. If the simplified (temperature-independent) material properties are used, incorrect results will be obtained.
Abstract: In this paper, the thermo-electro-structural coupledfield
in a cracked metal plate is studied using the finite element
analysis. From the computational results, the compressive stresses
reveal near the crack tip. This conclusion agrees with the past
reference. Furthermore, the compressive condition can retard and stop
the crack growth during the Joule heating process.