[Date Index] [Thread Index] [Author Index]

NDSolve

• To: mathgroup at smc.vnet.net
• Subject: [mg21471] NDSolve
• From: Klaus Wallmann <kwallmann at geomar.de>
• Date: Tue, 11 Jan 2000 04:17:50 -0500 (EST)
• Sender: owner-wri-mathgroup at wolfram.com

Using MATHEMATICA Version 4.0 on a Pentium III PC with Windows NT Version
4, I tried to solve the following ordinary homogeneous non-linear second
order differential equation with variable coefficients:

y''[t] + p[t] y'[t] + q[t] y[t]/(y[t]+K)  = 0

with boundary conditions

y[10] = 29

y'[6000] = 0

and

K = 1

p[t] = ((-1.15301 (-3 + ln[(0.769 + 0.102 exp(-0.036 t))^(2)]) + 0.2307
exp(+0.036 t) (-1 + ln[(0.769 + 0.102 exp(-0.036 t))^(2)])^(2))/(314 (0.871
+ 0.769 (-1 + exp(+0.036 t) (-1 + ln[(0.769 + 0.102 exp(-0.036 t))^(2)]))

q[t] = -[0.00203318 (0.231 - 0.102 exp(-0.036 t)) (0.102 (0.697676 -
exp(-0.036 t))+ 0.008316 (93.2 + t))^(-1.142) (1 - ln[(0.769 + 0.102
exp(-0.036 t))^(2)])]/(0.769 + 0.102 exp (-0.036 t))

I tried NDSolve to solve this equation but I did not succeed.

Is it possible to solve this equation or similar differential equations
using the numerical procedures implemented in MATHEMATICA? 

Sincerely

Klaus Wallmann