Kurs_vysshei_matematiki_UP_Berkov_N.A._2007-2
.pdft\x
t = 0 t = 0, 2 t = 0, 4 t = 0, 6 t = 0, 8 t = 1, 0
100 |
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80 |
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t=0 |
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t=0,2 |
60 |
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t=0,4 |
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t=0,6 |
40 |
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t=0,8 |
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t=1,0 |
20 |
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0 |
0,2 |
0,4 |
0,6 |
0,8 |
1 |
τ 0, 5 ·(a ·h)2
Ox
ORIGIN := 0 |
T OL := 0.00001 L := 1 |
a := 1 T max := 1 |
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r := 1 M := 100 h := |
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τ := r · |
h 2 |
N := |
T max |
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M |
a |
τ |
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hP r |
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L |
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M hP r := |
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τ P r := 0.2 |
hP r := 0.1 |
M P r := |
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h |
hP r |
Ck k = 1, 2, . . . λk = kπ/l
λk = kπ/l sin(kπx/l)
(0, l)
T (t) λk = kπ/l
Tk(t)
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kπa |
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2 |
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Tk (t) + |
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Tk(t) = 0. |
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s2 + |
kπa |
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2 |
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= 0 |
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l |
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s1,2 = ± |
kπa |
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l |
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Tk(t) = Ak cos |
kπat |
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+ Bk sin |
kπat |
, |
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l |
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l |
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Ak Bk
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kπx |
· Ak cos |
kπat |
kπat |
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uk(x, t) = Ck sin |
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+ Bk sin |
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l |
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l |
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l |
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CkAk = ak CkBk = bk |
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uk(x, t) |
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kπat |
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kπat |
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kπx |
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uk(x, t) = ak cos |
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+ bk sin |
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· sin |
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. |
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l |
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l |
l |
uk(x, t)
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ak cos |
kπat |
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kπat |
· sin |
kπx |
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∞ |
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u(x, t) = k=1 |
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+ bk sin |
l |
l |
. |