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Consistent units

Definition of a consistent system of units (required for LS-DYNA):

  • 1 force unit = 1 mass unit * 1 acceleration unit

  • 1 acceleration unit = 1 length unit / (1 time unit)^2

  • 1 density unit = 1 mass unit / (1 length unit)^3

The following table provides examples of consistent systems of units. As points of reference, the mass density and Young's Modulus of steel are provided in each system of units. "GRAVITY" is gravitational acceleration.

 

MASS LENGTH TIME FORCE STRESS ENERGY DENSITY YOUNG's 35MPH    
56.33KMPH
GRAVITY
kg  
m s N Pa J 7.83e+03 2.07e+11 15.65 9.806
kg cm s 1.0e-02 N 7.83e-03 2.07e+09 1.56e+03 9.806e+02
kg cm ms 1.0e+04 N 7.83e-03 2.07e+03 1.56 9.806e-04
kg cm us 1.0e+10 N 7.83e-03 2.07e-03 1.56e-03 9.806e-10
kg mm ms kN GPa kN-mm 7.83e-06 2.07e+02 15.65 9.806e-03
g cm s dyne dyne/cm² erg 7.83e+00 2.07e+12 1.56e+03 9.806e+02
g cm us 1.0e+07 N Mbar 1.0e+07 Ncm 7.83e+00 2.07e+00 1.56e-03 9.806e-10
g mm s 1.0e-06 N Pa 7.83e-03 2.07e+11 1.56e+04 9.806e+03
g mm ms N MPa N-mm 7.83e-03 2.07e+05 15.65 9.806e-03
ton mm s N MPa N-mm 7.83e-09 2.07e+05 1.56e+04 9.806e+03
lbf-s²/in in s lbf psi lbf-in 7.33e-04 3.00e+07 6.16e+02 386
slug ft s lbf psf lbf-ft 1.52e+01 4.32e+09 51.33 32.17

kgf-s²/mm mm s kgf kgf/mm² kgf-mm 7.98e-10 2.11e+04 1.56e+04 9.806e+03
kg mm s mN 1.0e+03 Pa 7.83e-06 2.07e+08 9.806e+03
g cm ms 1.0e+1 N
1.0e+05 Pa 7.83e+00 2.07e+06 9.806e-04