Consistency of Units
AIM
LS-DYNA doesn't have a default system of units. We have to input material properties and physical dimensions according to a consistent system of units as per our choice. This warrants that to use LS-DYNA in different circumstances, users has to be conversant with converting quantities from one system of units to another.
And also write a detailed report on unit conversion with calculations and with there units.
Value of the following measurements are given as follows:
MASS 1kg
LENGTH 1m
TIME 1s
FORCE 1N
STRESS 1Pa
ENERGY 1Nm
DENSITY 1Kg/m3
YOUNG'S Modulus 210GPa
Velocity 56.33KMPH
GRAVITY 9.8m/s2
Now, here are a few system of units:
Kg cm ms
Kg cm s
gm mm ms
kg m s
g cm s
g cm us
g mm s
ton mm s
slug ft s
kg mm s
g cm ms
kg mm ms
DIFFERENT TYPES SYSTEMS
- CGS SYSTEM
- FPS SYSTEM
- MKS SYSTEM
PROCEDURE
As per the requirement I'd explained below with detail calculation for conversion from SI unit to gm/mm/ms. I'd also plotted table below.
SI unit for gm mm ms
Mass 1 Kg = 1000gm
Length 1 m = 1000mm
Time 1 s = 1000 ms
Force 1 N = (1Kg*m)/s^2
(1000gm*1000mm)/(1000ms*1000ms)
( 1 gm * mm)/ms^2
Stress 1pa = N/m^2 = [(1gm *mm/ms^2]/(1000ms*1000ms)
= 10^-6gm/,,*ms^2.
Energy 1 Nm = [(1kg*m/s^2]*(1000mm)
= 10^3gm*mm^2/ms^2
DENSITY 1Kg/m3 = 1000gm/(10^3 ms)^3
= 10^3 gm/10^9 ms^3
= 10^-6 gm/ms^3
Youngs's Modulus 210Gpa { 1Gpa = 10^9 × (N/m^2)}
210 Gpa = 210 × [10^9 ×(N/m^2)]
= 210[10^9 × (10^-6gm/mm*ms^2)]
= 210 × 10^3 gm/mm*ms^2
= 210000 gm/mm*ms^2.
Velocity [1Km = 10^6mm]
1KMPH = 10^6mm/(3600*1000ms) [1HR = 3600*1000ms]
10/36 = 0.277mm/ms
56.33 KMPH = 56.33×0.277
= 15.64 mm/ms
GRAVITY 9.8m/s2
1m/s2 = 1000mm/ (1000ms × 1000ms )
= 10-3 mm/ms^2
9.8 m/s2 = 9.8 × 10^-3 mm/ms^2.
|
UNITS |
MASS |
LENGTH |
TIME |
FORCE |
STRESS |
ENERGY |
DENSITY |
YOUNG’S MODULUS |
VELOCITY |
GRAVITY |
|
|
Kg cm ms |
1 kg |
100m |
1000ms |
10^-4 Kg*cm/ms^2 |
10^ -8Kgcm/ms^2 |
10^-2 Kg*cm^2/ms^2 |
10^-6 Kg/cm^3 |
210 Kg/cm*ms^2 |
156.4*10^-2cm/ms |
9.8*10^-4 cm/ms^2 |
|
|
Kg cm s |
1kg |
100cm |
1 s |
10^2 Kg*cm/s^2 |
10^-2 Kg/cm*s^2 |
10^4 Kg*cm^2/s^2 |
10^-6 Kg/cm^3 |
210*10^7 Kg/cm*s^2 |
15647.22 cm/s` |
980 cm/ s^2 |
|
|
Gm mm ms |
1000 gm |
1000 mm |
1000 ms |
1 gm *mm/ms^2 |
10^-6 gm/mm * ms^2 |
10^3 gm*mm^2/ ms^2 |
10^-6 Gm/mm^3 |
210000 Gm/mm*ms^2 |
15.64 Mm/ms |
9.8* 10^-3 mm/ms^2 |
|
|
1 Kg | 1 m | 1 s | 1 Kg *m/s^2 | 1 Kg *m/s^2 | Kg *m^2/s^2 | Kg/m^3 | 210* 10 ^ 9 Kg/m*s^2 | 15.64 m/s | 9.8 m/ s^2 | |
| g cm s | 1000gm | 100 cm | 1 s | 10 ^5 g*cm/s^2 | 10 g*cm/s^2 | 10^7 g * cm ^2/s ^2 | 10^-3 g/cm | 210*10^10 g/cm*s^2 | 1564.7 cm/s | 980 cm/s^2 | |
| g cm us | 1000gm | 100cm | 1000000 us | 10^-7 gm*cm/us^2 | 10^-11 gm/cm*us^2 | 10^-5gm*cm^2/us^2 | 10gm/cm | 210*10^-2 gm/cm*us^2 |
1564.710^-6 cm/us |
9.8*10^-10 cm/us^2 | |
| g mm s | 1000 gm | 1000 mm | 1 s | 10^6 gm*mm/s^2 | 1 gm/mm*s^2 | 10^9 gm*mm^2/s^2 | 10^-6 gm/mm^3 | 210*10^9 gm/mm*s^2 | 15647.2 mm/s | 9.8*10^3 m/s^2 | |
| Ton mm s | 0.001 ton | 1000 mm | 1 s | 1 ton * mm/s^2 | 10^-6 ton/mm*s^2 | 10^3 ton*mm^2/s^2 | 10^-12 ton/mm^3 | 210*10^3 ton/mm*s^2 | 15647 mm/ms | 9.8*10^3mm/s^2 | |
| Slug ft s | 0.068 slug | 3.28 ft | 1 s | 0.223 slug*ft/s^2 | 0.020 slug/ft*s^2 | 0.731 slug/ft*s^2 | 1.92*10^-3 slug/ft^3 | 4.2*10^9 slug/ft*s^2 | 51.33ft/s | 32.144ft/s^2 | |
| Kg mm s | 1 kg | 1000 mm | 1 s | 1000kg*mm/s^2 | 10^-3 Kg/mm*s^2 | 10^6 Kg/mm^3 | 10^-9 Kg/mm^3 | 210 * 10^6Kg/mm*s^2 | 15647.22mm/s | 9.8*10^3m/s^2 | |
|
1000 gm | 100 cm | 1000 ms | 0.1g*cm/ms^2 | 10^-5 gm/cm*ms^2 | 10 g*cm^2/ms^2 | 10^-6 gm/cm^3 | 210*10^4 gm/cm*ms^2 | 1564*10^-3 cm/s^2 | 9.8*10^-4 cm/s^2 | |
| Kg mm ms | 1 kg | 1000 mm | 1000 ms |
10^-3 Kg*mm/ms^2 |
10^-9 Kg/mm*ms^2 | 1 kg*mm^2/ms^2 | 10^-9 Kg/mm^3 | 210 Kg/mm*ms^2 | 15647*10^-3 mm/ms | 9.8*10^-3 mm/ms^2 |