Week 11 Car Crash simulation

CAR CRASH SIMULATION

AIM :

TO PERFORM A CAR CRASH SIMULATION AND TO EVALUATE THE RESULTS USING ONE HALF OF THE CAR BODY WITH THREE DIFFERENT THICKNESS ON THE BODY OF THE CAR .

MODEL:

THE GIVEN MODEL HAS BEEN DIVIDED IN TO HALF OF THE ORIGINAL MODEL. SINCE THE OTHER SIDE OF THE MODEL IS A MIRROR OF THE EXISTING ONE AND A WALL WHICH WHICH IS ALSO DIVIDED IN TO HALF.

MATERIAL :

THE MATERIAL HAS BEEN ALLOTED ACCORDINGLY. FOR THE CAR BODY IT IS GIVEN AS STRUCTURAL STEEL NL , WHEREAS FOR THE WALL IT IS GIVEN AS STRUCTURAL STEEL.

STRUCTURAL STEEL:

STRUCTURAL STEEL NL :

CONNECTIONS:

THE DEFAULT CONTACTS HAS BEEN DETECTED BY THE SOLVER ITSELF , FOR THE EXPLICIT DYNAMICS WE DONT CONSIDER THE CONACT FORCES , SINCE THERE IS HUGE IMPACT ON THE BODIES .

BODY INTERACTIONS HAS BEEN ALLOTED TO TRAJECTORY ITSELF.

MESH:

FOR CREATING A MESH IN THIS PROJECT , WE NEED TO ANALYSE THE MODEL , WE ARE NOW FOCUSED ON THE ARE OF THE CONTACT , WHERE THE BODY WILL BE COLLIDING WITH WALL, THE WALL HAS BEEN PROVIDED WITH THE TETRAHEDRAL ELEMENTS , WHERE AS ON THE CAR BODY THE MESH ELEMENTS WERE BEEN DIVIDED IN TO TWO BASIS, THE AREA WHERE THE CAR BODY COLLIDES WITH THE WALL IS PROVIDED WITH FACE SIZING OF 15mm MESH ELEMENTS AND THE REMAINING BODY HAS BEEN LEFT WITH 175mm MESH ELEMENTS.

SYMMETRY REGION :

SYMMETRY REGION IS USED WHEN THE MODEL CONSUMES MORE COMPUTATIONAL AND THE ANALYSIS TIME , SO THAT THE MODEL IS DIVIDED INTO EQUAL PARTS ACCORDINGLY WHERE THE REMAINING PART IS OF MIRROR TO THE EXISTING ONE .

HERE WE HAVE USED SYMMETRY REGION TO THE CAR BODY AND THE WALL. SO THAT A COMPLETE CAR BODY CAN BE ANALYSED IN A EFFECIENT WAY .

ANALYSIS SETTINGS:

THE END TIME FOR THE EXPLICIT ANALYSIS HAS BEEN PROVIDED AS 0.002S.

FIXED SUPPORT :

A FIXED SUPPORT HAS BEEN ALLOTED TO SUPPORT THE CAR BODY FROM THEH OTHER SIDE SO THAT IT CAN WITHOLD THE HUGE IMPACT LOAD ON THE OTHER END OF THE MODEL.

DISPLACEMENT:

THE WALL IS PROVIDED WITH A DISPLACEMENT OF 1000mm , TO TRAVEL ALONG THE DIRECTION OF THE CAR IN THE Z – DIRECTION .

CASE 1 : THICKNESS - 0.3 mm

TOTAL DEFORMATION :

EQUIVALENT STRAIN ( VON- MISES) :

EQUIVALENT STRESS (VON-MISES):

FROM THE ABOVE SIMULATION WE CAME TO KNOW THAT THE STRESS GENERATED ON THE CAR BODY WITH THE DISPLACEMENT OF 1000mm ON THE WALL IS 76852 MPa.

PARAMETER STUDY :

PARAMETER IS THE MOST EFFICIENT WAY TO ANALYSE FOR THE DIFFERENT VALUES OF INPUT TO GET THE OUTPUT RESULT VALUES .

WHEN THE SIMULATION REQUIRES MORE TIME TO GENERATE AND CONSIDERING THE COMPUTATIONAL COST , WE ARE IMPLEMENTING THE PARAMETER STUDY , HERE WE NEED THE RESULTS FOR THE DIFFERENT VALUES OF THICKNESS OF THE BODY.

FOR THIS WE NEED TO CHECK THE VALUES OF THICKNESS AS INPUT AND ALSO TO CHECK THE DESIRED OUTPUTS – TOTAL DEFORMATION , EQUIVALENT STRESS , EQUIVALENT STRAIN .

FROM THE PARAMETRIC STUDY WE CAN COME TO CONCLUDE THAT THE STRESS GENERATED ON THE BODY WITH THE THICKNESS

• CASE 2 - 0.4 mm == EQUIVALENT STRESS - 86578 MPa
• CASE 3 - 0.5 mm == EQUIVALENT STRESS -8258.4 MPa

RESULT :

FROM THE ABOVE SIMULATION WE COME TO CONCLUDE THAT , USING PARAMETER STUDY CAN REDUCE THE ANALYSIS TIME AND COMPUTATIONAL COST EFFICIENT WAY FOR LARGE SIMULATIONS AND BY

INCREASING THE THICKNESS OF THE CAR BODY CAN ACTUALLY REDUCE THE STRAIN DEVELOPED IN IT .