## General Mechanical

#### Need Help with Welding Simulation using Goldak Heat Source.

• Abdullah2021
Subscriber

Hi there!

Hope Everyone is doing fine.

I am a student conducting arc welding simulation in ANSYS. The voltage: V = 24 volt, Current I = 75 Amp and efficiency = 0.6. Plate Dimensions are 300 x 300 x 2 mm****3 . I am implementing goldak heat source model(ref: https://www.youtube.com/watch?v=hXLRsagT_ZI&ab_channel=S.B). The code is as follows:

Commands inserted into this file will be executed just prior to the ANSYS SOLVE command.

! These commands may supersede command settings set by Workbench.

! Active UNIT system in Workbench when this object was created: Metric (mm, kg, N, s, mV, mA)

! NOTE: Any data that requires units (such as mass) is assumed to be in the consistent solver unit system.

CMSEL,ALL

*GET,EMAX,ELEM,,NUM,MAX

*GET,EMIN,ELEM,,NUM,MIN

ALLSEL

TIME_WELD=60

DT=1

A=2.9315

B=2

C1=3.81

C2=7.622

TAU=0

FF=0.6

FR=1.4

Q=1080

VEL=5

NPT=TIME_WELD/DT

NROPT, FULL

*DO,i,1,NPT,1

WTIME=(i)

TIME,WTIME

HCENTER=VEL*WTIME

*DO,jj,EMIN,EMAX,1

X=CENTRX(jj)

Y=CENTRY(jj)

Z=CENTRZ(jj)

CSI=-Z+VEL*(TAU-WTIME)

*IF,Z,GT,HCENTER,THEN

C=C1

F=FF

*ELSE

C=C2

F=FR

*ENDIF

PART1=(6*(3**0.5)*F*Q)/(A*B*C*3.14*(3.14**0.5))

PART2=(exp(-3*(X/A)**2))*(exp(-3*(Y/B)**2))*(exp(-3*(CSI/C)**2))

QF=PART1*PART2

BFE,jj,HGEN,,QF

*ENDDO

ALLSEL

SOLVE

*ENDDO

CMSEL,ALL

BFEDELE,ALL,ALL

I am also attaching temperature contours and the problem is the temperature won't even go beyond 100 C (may be its because of units but I have even used "m" in parameter definitions as in the reference video. But in that case no moving source is seen). Furthermore, the employed parameters of goldak are obtained from experiment and are in mm.

• Dave Looman
Ansys Employee
Check the solving units in the help and at the top of the solve.out (solution information) file. The solving units may not match the active units in the gui. If they are as expected hand calculate the expected rate of temperature rise based on total Q, approximate volume of elements, mass density and specific heat.n