Torsion Functional Forms
Torsion Functional Forms
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Torsion Functional Forms

Table 8.19. Torsion Functional Forms

NameKeywordNParams (Req)FormParamDefault
Cosinecos4 (3) U ϕ = k ( 1 + s cos ( n ϕ - ϕ eq ) ) k
n
ϕeq
s 1.0
Triple Cosinecos33 (3) U ϕ = 1 2 [ k 1 ( 1 + cos ( ϕ ) ) + k 2 ( 1 - cos ( 2 ϕ ) ) + k 3 ( 1 + cos ( 3 ϕ ) ) ] k1  
k2  
k3  
Quadruple Cosinecos44 (4) U ϕ = 1 2 [ k 1 ( 1 + cos ( ϕ ) ) + k 2 ( 1 - cos ( 2 ϕ ) ) + k 3 ( 1 + cos ( 3 ϕ ) ) + k 4 ( 1 - cos ( 4 ϕ ) ) ] k1  
k2  
k3  
k4  
Triple Cosine + Constantcos3c4 (4) U ϕ = k 0 + 1 2 [ k 1 ( 1 + cos ( ϕ ) ) + k 2 ( 1 - cos ( 2 ϕ ) ) + k 3 ( 1 + cos ( 3 ϕ ) ) ] k0  
k1  
k2  
k3  
Cosine Productcoscos3 (3) U ϕ = 1 2 k ( 1 - cos ( n ϕ eq ) cos ( n ϕ ) ) k  
n  
ϕeq  
Dreiding Cosinedreiding3 (3) U ϕ = 1 2 k ( 1 - cos ( n ( ϕ - ϕ eq ) ) ) k  
n  
ϕeq  

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