Dynamic compressive behaviour of hexagonal honeycombs with entrapped gas

MATLAB Codes of the theoretical model

Authors: Sri Datta Rapaka, Manoj Pandey and Ratna Kumar Annabattula

Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai, India

The codes given below are based on the below mentioned work published in the International Journal of Impact Engineering.
Sri Datta Rapaka, Manoj Pandey and Ratna Kumar Annabattula, Dynamic Compressive Behaviour of auxetic and non-auxetic hexagonal honeycombs with entrapped gas, International Journal of Impact Engineering, 146, 103718 (2020).

 

 

The following instructions help simulate the deformation process of the honeycomb structures with cell angles 15^o and 30^o, in the presence of the entrapped gas. The necessary MATLAB files and their functionalities are described below.

 

 

1)    The file to be executed for cell angle 30^o is MAIN_Motion_RepresentativeVolume_Theta30.m

 

2)    The file to be executed for cell angle 15^o is MAIN_Motion_RepresentativeVolume_Theta15.m

 

Upon successful execution of the main files, the average nominal stress required to crush the honeycomb structure at the specified strain-rate/impact velocity is obtained and displayed in the command window.

 

3)    The following function files are required to execute the main file.

a.     draw.m: Function to visualise the undeformed configuration of the structure being simulated. The representative system of cell walls are highlighted in black.

b.     animation.m: Function to visualise the deformation process.

c.     find_AreaCell.m: Function to compute the area of a cell based on the coordinates of the vertices of the cell.

d.     gas_constitutive_reln.m : Function to compute the gas pressure from the constitutive relation of the gas which has been described in the paper.

                           

4)    Before running the main file, the limits of the figures are to be checked in the function files draw.m, and animation.m.

  

5)    By default the function calls for draw.m and animation.m are commented out.

 

a.     For the cell angle 30^o, uncomment the function calls on lines 140 and 226 for visualising the results.

b.     For the cell angle 15^o, uncomment the function calls on lines 142 and 232 for visualising the results.

              

6)    The function calls for draw.m, and animation.m are written in separate sections of the code, and the users are encouraged to uncomment and run the respective sections, after executing the main file.