Week - 1 - Consistency of Units

LS-DYNA doesn't have a default system of units. User needs to input material properties and physical dimensions according to a consistent system of units as per their 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.

Objective: To convert the above given system into specified Unit system

Procedure: The unit conversion from SI to gm mm ms is given below

Mass 1Kg=1000gm=1*10^3 gm

Length 1m=1000mm=1*10^3 mm

Time 1s= 1000 ms =1*10^3 ms

Force 1N= 1 Kg m/s2=1(1000 gm*1000 mm)/(1000ms)2=1 gm mm/ms2

Stess 1Pa= 1N/m2=(1kg m/s2)=(1000gm*1000mm/(1000000ms2))=10^-6 gm mm ms2

Density 1kg/m3=1000 gm/10^9mm3=10^-6 gm/mm3

Velocity 56.33 Kmph=(56.33*10^6)/H=(56.33*10^6)/(3600*1000 ms)=15.647 mm/ms

Gravity 9.81 m/s2= 9.81( 1000 mm/(10^6ms2))=9

Units	MASS	LENGTH	TIME	FORCE	STRESS	ENERGY	DENSITY	YOUNG'S Modulus	Velocity	Gravity
Kg cm ms	1	100	10^3	10^-4	10^-8	10^-2	10^-6	21000	1.56472	9.81*10^-4
Kg cm s	1	100	1	10^2	10^-2	10^4	10^-6	210*10^7	1564.72	9.81*10^2
gm mm ms	10^3	1000	10^3	1	10^-6	10^3	10^-6	210*10^3	15.6472	9.81*10^-3
kg m s	1	1	1	1	1	1	1	210*10^9	15.6472	9.81
g cm s	10^3	100	1	10^5	10	10^7	10^-3	210*10^10	1564.72	9.81*10^2
g cm us	10^3	100	10^6	10^-7	10^-11	10^-5	10^-3	2.1	1564.72*10^-4	9.81*10^-10
g mm s	10^3	1000	1	10^6	1	10^9	10^-6	210*10^11	156472	9.81*10^3
ton mm s	10-3	1000	1	1	10^-6	10^3	10^-12	210*10^3	156472	9.81*10^3
slug ft s	0.068	3.28	1	0.224	0.0208	0.7366	1.93*10^-3	4.368	51.332	32.144
kg mm s	1	1000	1	10^3	10^-3	10^6	10^-9	210*10^6	156472	9.81*10^3
g cm ms	10^3	100	10^3	10^-1	10^-5	10	10^-3	210*10^4	1.56472	9.81*10^-4
kg mm ms	1	1000	10^3	10^-3	10^-9	1	10^-9	210	15.6472	9.81*10^-3