Excellence in Research and Innovation for Humanity

Thomas Jin Chee Liu

Publications

7

Publications

7
9999629
Compressive Stresses near Crack Tip Induced by Thermo-Electric Field
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.

Keywords:
Compressive stress, crack tip, Joule heating, finite element.
6
9100
Effects of Temperature-Dependent Material Properties on Stress and Temperature in Cracked Metal Plate under Electric Current Load
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.

Keywords:
Joule heating, temperature-dependent, crack tip, finite element.
5
17409
Notes on Vibration Design for Piezoelectric Cooling Fan
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.

Keywords:
Piezoelectric cooling fan, vibration, cantilever Euler beam, air flow.
4
9996990
Finite Element Analysis of Composite Frames in Wheelchair under Upward Loading
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.

Keywords:
Wheelchair frame, stacking sequence, failure index, finite element.
3
9997099
Finite Element Analysis of Crack Welding Process
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.

Keywords:
Crack welding, contact pressure, Joule heating, finite element, coupled-field.
2
10003420
Numerical and Experimental Studies of Joule Heating Effects around Crack and Notch Tips
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.
Keywords:
Thermo-electric, Joule heating, crack tip, notch tip.
1
10003791
Performance of Piezoelectric Cooling Fan with Rectangular Blade
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. 
Keywords:
Piezoelectric cooling fan, finite element, vibration, natural frequency.