Assessment of Automobile Door Slam using Finite Element Method

Automotive cars have various types of doors. The swinging door is the most common & complicated parts because they are doing both functions, general guidelines of car style, & passenger's safety by protecting humans from side crashes. With the advent of Computer Aided Engineering (CAE), Finite Element Analysis (FEA) has become a necessity for the automotive industry to improve and validate all manner of automotive structures. The use of FEA in the design procedure has increased significantly making validation of the FE Models used is essential. A comparison with experimental results of Door slam testing is a very effective method to evaluate the accuracy of the FE Models used. The objective of the door slam testing is to determine acceleration, stress, strains & buckling energy induced while slamming action. In this door slam analysis carried out using CAE tools, Hypermesh-v12, Ls-Dyna. Door is slammed on rigid surface at velocity 1m/sec from opening angle 20 degree and results are evaluated for 0.35 seconds in the time step of 0.01second.Then predictability of the CAE method is examined through detailed comparison of experimental acceleration and strain results. While these results shows excellent agreement in CAE and test for accelerations on the outer panel. Also CAE predicts higher strains on the inner panel than the test. In addition, elastically buckling of outer panel is examined. These results of Acceleration, strain and buckling are also discussed in detail.

Use of PVDF Wires As Sensors for Non Intrusive Pressure Measurement

One of the most challenging aspects when performing on-site piping troubleshooting is to obtain the most pertinent information possible regarding piping behavior: acceleration, stress, pressure levels, etc. This last parameter is always difficult to obtain because when pressure taps are available on the line, they are rarely in the area of interest. PVDF (PolyVinyliDene Fluoride) wire makes it possible to perform non-intrusive pressure measurements but needs to be calibrated in order to have a good representation of phenomenon occurring inside the pipe. After development of a dedicated calibrator and calculation of the fluid/structure coupling coefficient, VibraTec is able to assess PVDF sensor sensitivity according to client’s installation characteristics. Non-intrusive measurements provide a good accuracy regarding phenomenon amplitude and frequency localization even though some temperature restrictions apply to PVDF measurements. Although PVDF sensors seem to be simple to implement, particular attention must be paid during installation as this has a direct influence on the PVDF response.

Research on Vibration Characteristics and Seismic Response of Shell of LNG Tank

Liquefied Natural Gas (LNG) tank is the important equipment in storage LNG. There has been a lot of research results abroad, but lack of seismic studies for the LNG tank in China. Domestic structural designers also have an urgent need for internal force and deformation law of LNG tanks under a variety of dynamic loads. This study focused on vibration characteristics and seismic response of a shell of LNG tank. Using ANSYS creat finite element model, obtain natural frequency and vibration mode etc. According to requirements of Chinese "code of building seismic design", analyze this shell of LNG tank of unidirectional horizontal seismic response under the action of selected three kinds of seismic waves. Time-history curves of LNG tank’s displacement, acceleration, stress distribution law under the action of selected three kinds of seismic waves are obtained.