Advanced Search

mehdi jafari

754 Reputation

13 Badges

11 years, 175 days
Contact mehdi jafari

MaplePrimes Activity


These are replies submitted by mehdi jafari

please enter your boundary conditions,...

mehdi jafari 754
April 21 2014
0 0

please enter your boundary conditions, and solve your pde via boundary conditions using pdsolve,numeric option .

tnx everyone,...

mehdi jafari 754
April 20 2014
0 0

@Alejandro Jakubi tnx everyone,i thought it is just for me since i have some browsers problem,really thanks for your answers. good luck

your picture is not visible?...

mehdi jafari 754
April 18 2014
0 0

your picture is not visible?

oh sorry then...

mehdi jafari 754
April 18 2014
0 0

@sarra   please have a good break,and take care,sorry .

at first it returns an error !...

mehdi jafari 754
April 18 2014
0 0

@mehdi jafari at first it returns an error ! 

executing this line :
int(convert(F,exp), z = 0 .. infinity,numeric, epsilon = 0.1e-1); # which returns 2.259350091#

but execute F again and it will return #2.259350091# !!!!
what's wrong with maple !!!

repetitive question...

mehdi jafari 754
April 18 2014
0 0

is it this link question ? http://www.mapleprimes.com/questions/201416-Plotting-Of-Piecewise-Continuous-Function

make sure of two things !...

mehdi jafari 754
April 17 2014
0 0

@sukma if your answers are not of your interest,maybe you want to check two things !


first be sure of your TC is correct and second your t2 is exactly what you want ,

restart:
TC := (p*A*((lambda-sigma)*(exp(lambda*t2)-1)+lambda*(exp((lambda-sigma)*T)-exp((lambda-sigma)*t2)))/(lambda*(lambda-sigma))-Ca-A*exp(lambda*t1)*((beta*a2+b2)*(exp(beta*t1)-1)/beta^2-(lambda*a2-b2)*(1-exp(-lambda*t1))/lambda^2)/(beta+lambda)+A*exp(lambda*t1)*b2*t1/(lambda*beta)-W*((alpha*a1+b1)*(1-exp(-alpha*t1))-alpha*b1*t1*exp(-alpha*t1))/alpha^2+A*(exp(lambda*t2)*((a1+b1*t2)*lambda*alpha+b1*(lambda-alpha))-exp(lambda*t1)*(b1*(alpha^2-lambda^2*exp((lambda+alpha)*(t2-t1)))-(a1+b1*t1)*lambda*alpha*(alpha+lambda*exp((lambda+alpha)*(t2-t1))))/(lambda+alpha))/(lambda^2*alpha^2)+Cs*A*exp((lambda-sigma)*t2)*((T-t2)*(lambda-sigma)-exp((T-t2)*(lambda-sigma))+1)/(lambda-sigma)^2-L*A*((exp(lambda*T)-exp(lambda*t2))/lambda-(exp((lambda-sigma)*T)-exp((lambda-sigma)*t2))/(lambda-sigma))-C*(A*(exp((beta+lambda)*t1)-1)/(beta+lambda)+W+A*(exp((lambda-sigma)*T)-exp((lambda-sigma)*t2))/(lambda-sigma)))/(T);

# and make sure of this #

t2 = (ln(W*(lambda+alpha)/A)+(lambda+alpha)*t1)/(lambda+alpha);

# if these two are correct,thus your answers are surely correct ! #

 

 

too interesting !...

mehdi jafari 754
April 17 2014
0 0

it is too interesting that you appreciate the answer , but you do not vote it up ! :)

your are very welcome,...

mehdi jafari 754
April 17 2014
0 0

@italopersechino your are very welcome,and a very good and modest guy.

u have repeated your answers so much !...

mehdi jafari 754
April 17 2014
0 0

u have repeated your answers so much !   but i could not find out what is going to be solved ?! i can not undertand what do u mean unless you explain in algebric expreesions that what are your knowns,what are your unknowns ,what are your equataions, and what is going to be solved. please delet your reapetitive replies. tnx

too easy...

mehdi jafari 754
April 17 2014
0 0

@italopersechino just put # in the lines which define x1 and PZc , that's all !


``

> 

restart:
with(linalg):
with(plots):
Digits:=15:
> 

#E:=214000: sig_Y:=853: n:=0.0595: eps_f:=1.1005:
#R:=0.1: dK_th:=4.2: c:=-0.679: nu:=0.3: dK:=100:
> 

P_str_fact:=1/(1-2*nu):
> 

#pi:=3.141592654:
> 

 

> 

#Size of plastic zone at dK
#PZc:=(1/((4*pi*P_str_fact^2)*(1+n)))*(dK/sig_Y)^2; #[m]
> 

#Size of plastic zone at dK=dK_th
#x1:=(1/((4*pi*P_str_fact^2)*(1+n)))*(dK_th/sig_Y)^2; #[m]
> 

#Strain plastic amplitude along crack ligament (r)
deps:=(2*sig_Y/E)*(PZc/(r+x1))^(1/(1+n));

2*sig_Y*(PZc/(r+x1))^(1/(1+n))/E

 (1)
> 

deps_tip:=subs(r=0,deps);

2*sig_Y*(PZc/x1)^(1/(1+n))/E

 (2)
> 

deps_PZc:=subs(r=PZc-x1,deps);

2*sig_Y/E

 (3)
> 

 

> 

 

> 

#LCF
depsLCF:=2*eps_f*(2*Nf)^c;

2*eps_f*(2*Nf)^c

 (4)
> 

Nf:=1/Dam;

1/Dam

 (5)
> 

 

> 

appo:=depsLCF=deps;

2*eps_f*(2/Dam)^c = 2*sig_Y*(PZc/(r+x1))^(1/(1+n))/E

 (6)
> 

Damage:=solve(appo,Dam);

2*(sig_Y*(PZc/(r+x1))^(1/(1+n))/(E*eps_f))^(-1/c)

 (7)
> 

eval(%,{PZc=(1/((4*pi*P_str_fact^2)*(1+n)))*(dK/sig_Y)^2,x1=(1/((4*pi*P_str_fact^2)*(1+n)))*(dK_th/sig_Y)^2});

2/(sig_Y*(dK^2*(-1+2*nu)^2/(4*n*pi*r*sig_Y^2+4*dK_th^2*nu^2+4*pi*r*sig_Y^2-4*dK_th^2*nu+dK_th^2))^(1/(1+n))/(E*eps_f))^(1/c)

 (8)
> 

 

> 

 

NULL


Download Fatigue_crack_growth_(1).mw

please insert your full code here...

mehdi jafari 754
April 17 2014
0 1

@Kinkilla please insert your full code here so that we can completly understand what u are talking about !

please write your code completely here ,...

mehdi jafari 754
April 16 2014
0 0

@Hb i think u can easily do what u want,but please insert your code here so that we can help. good luck! what do u mean by specifying nodes on x axis ?  u can insert a sequence of numbers like this :
[seq](x,x=0..1,0.01);

u can also plot your list with listplot command. for more help please insert your code fully here. tnx

hmm...

mehdi jafari 754
April 15 2014
0 0

@Preben Alsholm thus what's wrong with this problem?

i replaced but it does not change the an...

mehdi jafari 754
April 15 2014
0 0


 

> 

restart
> 

TC := (p*A*((lambda-sigma)*(exp(1)^(lambda*t2)-1)+lambda*(exp(1)^((lambda-sigma)*T)-exp(1)^((lambda-sigma)*t2)))/(lambda*(lambda-sigma))-Ca-A*exp(1)^(lambda*t1)*((beta*a2+b2)*(exp(1)^(beta*t1)-1)/beta^2-(lambda*a2-b2)*(1-exp(1)^(-lambda*t1))/lambda^2)/(beta+lambda)+A*exp(1)^(lambda*t1)*b2*t1/(lambda*beta)-W*((alpha*a1+b1)*(1-exp(1)^(-alpha*t1))-alpha*b1*t1*exp(1)^(-alpha*t1))/alpha^2+A*(exp(1)^(lambda*t2)*((a1+b1*t2)*lambda*alpha+b1*(lambda-alpha))-exp(1)^(lambda*t1)*(b1*(alpha^2-lambda^2*exp(1)^((lambda+alpha)*(t2-t1)))-(a1+b1*t1)*lambda*alpha*(alpha+lambda*exp(1)^((lambda+alpha)*(t2-t1))))/(lambda+alpha))/(lambda^2*alpha^2)+Cs*A*exp(1)^((lambda-sigma)*t2)*((T-t2)*(lambda-sigma)-exp(1)^((T-t2)*(lambda-sigma))+1)/(lambda-sigma)^2-L*A*((exp(1)^(lambda*T)-exp(1)^(lambda*t2))/lambda-(exp(1)^((lambda-sigma)*T)-exp(1)^((lambda-sigma)*t2))/(lambda-sigma))-C*(A*(exp(1)^((beta+lambda)*t1)-1)/(beta+lambda)+W+A*(exp(1)^((lambda-sigma)*T)-exp(1)^((lambda-sigma)*t2))/(lambda-sigma)))/T:
> 

TC2 := subs(t2 = (ln(W*(lambda+alpha)/A)+(lambda+alpha)*t1)/(lambda+alpha), TC):
> 

x1 := diff(TC2, t1) = 0:
> 

 x2 := diff(TC2, T) = 0:
> 

x3 := evalf(simplify(lhs(eval(x1,{A = 290, lambda = 4, a1 = .9, a2 = 2.4, b2 = 0.1e-1, b1 = 0.1e-2, alpha = 0.2e-1, beta = 0.4e-1, W = 90, Ca = 100, L = 11, C = 9, p = 12, Cs = 4, sigma = 0.2e-2}))));

(20445.79790*exp(.2201100996+4.*t1)-4123.831928*exp(.2200000446+3.998000000*t1)-21822.50000*exp(4.04*t1)+36381.92537*exp(4.*t1)+90.57213930*exp(4.*t1)*t1-81.*exp(-0.2e-1*t1)-0.9000000000e-1*t1*exp(-0.2e-1*t1)+14.50000000*exp(.2201100996+4.*t1)*t1+1160.*exp(.2200000446+3.998000000*t1)*T-1160.*exp(.2200000446+3.998000000*t1)*t1)/T

 (1)
> 

x4 := evalf(simplify(lhs(eval(x2,{A = 290, lambda = 4, a1 = .9, a2 = 2.4, b2 = 0.1e-1, b1 = 0.1e-2, alpha = 0.2e-1, beta = 0.4e-1, W = 90, Ca = 100, L = 11, C = 9, p = 12, Cs = 4, sigma = 0.2e-2}))));

(3769.854928*T*exp(3.998*T)+5451.984839-3190.*T*exp(4.*T)-5110.543225*exp(.2201100996+4.*t1)-942.9351996*exp(3.998*T)+958.9011648*exp(.2200000446+3.998000000*t1)+5401.608911*exp(4.04*t1)-9089.820585*exp(4.*t1)-22.64303483*exp(4.*t1)*t1-4275.*exp(-0.2e-1*t1)-4.500000000*t1*exp(-0.2e-1*t1)-3.625000000*exp(.2201100996+4.*t1)*t1+290.1450725*exp(.2200000446+3.998000000*t1)*t1+797.5000000*exp(4.*T))/T^2

 (2)
> 

x5 := solve({x3, x4}, {T, t1});
> 

 

Warning, solutions may have been lost

  

"x5:="

 (3)
> 

``

``


Download solution_have_los.mw

First 9 10 11 12 13 14 15 Last Page 11 of 23