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Good day community, I try to solve the 2D heat equation in cylindrical coordinates. I wanna follow a paper (Selim et al.: Temperature rise in a semi-infinite medium heated by a disc source) and therefortherefore using a Laplace transform and a Hankel transform, subsequently, and there I encountered a problem.

I'll jump right in, my equation is:

eqn = D[T[r, z, t], {r, 2}] + 1/r D[T[r, z, t], r] + 
   D[T[r, z, t], {z, 2}] == 1/[Alpha] D[T[r, z, t], t]

lapl = LaplaceTransform[eqn,t,p] gives me a ,what I understand is a, correct result:

LaplaceTransform[(T^(0,2,0))[r,z,t],t,p]+LaplaceTransform[(T^(1,0,0))[r,z,t],t,p]/r+
LaplaceTransform[(T^(2,0,0))[r,z,t],t,p]==
(p LaplaceTransform[T[r,z,t],t,p]-T[r,z,0])/[Alpha]

However, when applying HankelTransform[lapl,r,s,0] the result I'm getting is:

HankelTransform[LaplaceTransform[(T^(0,2,0))[r,z,t],t,p],r,s,0]+
HankelTransform[LaplaceTransform[(T^(1,0,0))[r,z,t],t,p]/r,r,s,0]+
HankelTransform[LaplaceTransform[(T^(2,0,0))[r,z,t],t,p],r,s,0]==
(1/[Alpha])(p HankelTransform[LaplaceTransform[T[r,z,t],t,p],r,s,0]-
HankelTransform[T[r,z,0],r,s,0])`

while, based on the paper, I'm supposed to get:

$$\frac{\mathrm d^2 \overline{T_0}}{\mathrm dz^2}-\left(s^2+\frac{p}{\alpha}\right)\overline{T_0}=0$$

(In case the output is to tiring to read, as summary: there is no occurrence of s whatsoever, which makes doubt the correctness.)

Do I use the functions in wrong way (which I suppose is more likely) or is Mathematica (11.2) not able to transform this kind of input. Thanks in advance and forgive me my poor formatting skills.

Good day community, I try to solve the 2D heat equation in cylindrical coordinates. I wanna follow a paper (Selim et al.: Temperature rise in a semi-infinite medium heated by a disc source) and therefor using a Laplace transform and a Hankel transform, subsequently, and there I encountered a problem.

I'll jump right in, my equation is:

eqn = D[T[r, z, t], {r, 2}] + 1/r D[T[r, z, t], r] + 
   D[T[r, z, t], {z, 2}] == 1/[Alpha] D[T[r, z, t], t]

lapl = LaplaceTransform[eqn,t,p] gives me a ,what I understand is a, correct result:

LaplaceTransform[(T^(0,2,0))[r,z,t],t,p]+LaplaceTransform[(T^(1,0,0))[r,z,t],t,p]/r+
LaplaceTransform[(T^(2,0,0))[r,z,t],t,p]==
(p LaplaceTransform[T[r,z,t],t,p]-T[r,z,0])/[Alpha]

However, when applying HankelTransform[lapl,r,s,0] the result I'm getting is:

HankelTransform[LaplaceTransform[(T^(0,2,0))[r,z,t],t,p],r,s,0]+
HankelTransform[LaplaceTransform[(T^(1,0,0))[r,z,t],t,p]/r,r,s,0]+
HankelTransform[LaplaceTransform[(T^(2,0,0))[r,z,t],t,p],r,s,0]==
(1/[Alpha])(p HankelTransform[LaplaceTransform[T[r,z,t],t,p],r,s,0]-
HankelTransform[T[r,z,0],r,s,0])`

while, based on the paper, I'm supposed to get:

$$\frac{\mathrm d^2 \overline{T_0}}{\mathrm dz^2}-\left(s^2+\frac{p}{\alpha}\right)\overline{T_0}=0$$

(In case the output is to tiring to read, as summary: there is no occurrence of s whatsoever, which makes doubt the correctness.)

Do I use the functions in wrong way (which I suppose is more likely) or is Mathematica (11.2) not able to transform this kind of input. Thanks in advance and forgive me my poor formatting skills.

Good day community, I try to solve the 2D heat equation in cylindrical coordinates. I wanna follow a paper (Selim et al.: Temperature rise in a semi-infinite medium heated by a disc source) and therefore using a Laplace transform and a Hankel transform, subsequently, and there I encountered a problem.

I'll jump right in, my equation is:

eqn = D[T[r, z, t], {r, 2}] + 1/r D[T[r, z, t], r] + 
   D[T[r, z, t], {z, 2}] == 1/[Alpha] D[T[r, z, t], t]

lapl = LaplaceTransform[eqn,t,p] gives me a ,what I understand is a, correct result:

LaplaceTransform[(T^(0,2,0))[r,z,t],t,p]+LaplaceTransform[(T^(1,0,0))[r,z,t],t,p]/r+
LaplaceTransform[(T^(2,0,0))[r,z,t],t,p]==
(p LaplaceTransform[T[r,z,t],t,p]-T[r,z,0])/[Alpha]

However, when applying HankelTransform[lapl,r,s,0] the result I'm getting is:

HankelTransform[LaplaceTransform[(T^(0,2,0))[r,z,t],t,p],r,s,0]+
HankelTransform[LaplaceTransform[(T^(1,0,0))[r,z,t],t,p]/r,r,s,0]+
HankelTransform[LaplaceTransform[(T^(2,0,0))[r,z,t],t,p],r,s,0]==
(1/[Alpha])(p HankelTransform[LaplaceTransform[T[r,z,t],t,p],r,s,0]-
HankelTransform[T[r,z,0],r,s,0])`

while, based on the paper, I'm supposed to get:

$$\frac{\mathrm d^2 \overline{T_0}}{\mathrm dz^2}-\left(s^2+\frac{p}{\alpha}\right)\overline{T_0}=0$$

(In case the output is to tiring to read, as summary: there is no occurrence of s whatsoever, which makes doubt the correctness.)

Do I use the functions in wrong way (which I suppose is more likely) or is Mathematica (11.2) not able to transform this kind of input. Thanks in advance and forgive me my poor formatting skills.

added 51 characters in body
Source Link

Good day community, I try to solve the 2D heat equation in cylindrical coordinates. I wanna follow a paper (Selim et al.: Temperature rise in a semi-infinite medium heated by a disc sourceTemperature rise in a semi-infinite medium heated by a disc source) and therefor using a Laplace transform and a Hankel transform, subsequently, and there I encountered a problem.

I'll jump right in, my equation is:

eqn = D[T[r, z, t], {r, 2}] + 1/r D[T[r, z, t], r] + 
   D[T[r, z, t], {z, 2}] == 1/[Alpha] D[T[r, z, t], t]

lapl = LaplaceTransform[eqn,t,p] gives me a ,what I understand is a, correct result:

LaplaceTransform[(T^(0,2,0))[r,z,t],t,p]+LaplaceTransform[(T^(1,0,0))[r,z,t],t,p]/r+
LaplaceTransform[(T^(2,0,0))[r,z,t],t,p]==
(p LaplaceTransform[T[r,z,t],t,p]-T[r,z,0])/[Alpha]

However, when applying HankelTransform[lapl,r,s,0] the result I'm getting is:

HankelTransform[LaplaceTransform[(T^(0,2,0))[r,z,t],t,p],r,s,0]+
HankelTransform[LaplaceTransform[(T^(1,0,0))[r,z,t],t,p]/r,r,s,0]+
HankelTransform[LaplaceTransform[(T^(2,0,0))[r,z,t],t,p],r,s,0]==
(1/[Alpha])(p HankelTransform[LaplaceTransform[T[r,z,t],t,p],r,s,0]-
HankelTransform[T[r,z,0],r,s,0])`

while, based on the paper, I'm supposed to get:

$$\frac{\mathrm d^2 \overline{T_0}}{\mathrm dz^2}-\left(s^2+\frac{p}{\alpha}\right)\overline{T_0}=0$$

(In case the output is to tiring to read, as summary: there is no occurrence of s whatsoever, which makes doubt the correctness.)

Do I use the functions in wrong way (which I suppose is more likely) or is Mathematica (11.2) not able to transform this kind of input. Thanks in advance and forgive me my poor formatting skills.

Good day community, I try to solve the 2D heat equation in cylindrical coordinates. I wanna follow a paper (Selim et al.: Temperature rise in a semi-infinite medium heated by a disc source) and therefor using a Laplace transform and a Hankel transform, subsequently, and there I encountered a problem.

I'll jump right in, my equation is:

eqn = D[T[r, z, t], {r, 2}] + 1/r D[T[r, z, t], r] + 
   D[T[r, z, t], {z, 2}] == 1/[Alpha] D[T[r, z, t], t]

lapl = LaplaceTransform[eqn,t,p] gives me a ,what I understand is a, correct result:

LaplaceTransform[(T^(0,2,0))[r,z,t],t,p]+LaplaceTransform[(T^(1,0,0))[r,z,t],t,p]/r+
LaplaceTransform[(T^(2,0,0))[r,z,t],t,p]==
(p LaplaceTransform[T[r,z,t],t,p]-T[r,z,0])/[Alpha]

However, when applying HankelTransform[lapl,r,s,0] the result I'm getting is:

HankelTransform[LaplaceTransform[(T^(0,2,0))[r,z,t],t,p],r,s,0]+
HankelTransform[LaplaceTransform[(T^(1,0,0))[r,z,t],t,p]/r,r,s,0]+
HankelTransform[LaplaceTransform[(T^(2,0,0))[r,z,t],t,p],r,s,0]==
(1/[Alpha])(p HankelTransform[LaplaceTransform[T[r,z,t],t,p],r,s,0]-
HankelTransform[T[r,z,0],r,s,0])`

while, based on the paper, I'm supposed to get:

$$\frac{\mathrm d^2 \overline{T_0}}{\mathrm dz^2}-\left(s^2+\frac{p}{\alpha}\right)\overline{T_0}=0$$

(In case the output is to tiring to read, as summary: there is no occurrence of s whatsoever, which makes doubt the correctness.)

Do I use the functions in wrong way (which I suppose is more likely) or is Mathematica (11.2) not able to transform this kind of input. Thanks in advance and forgive me my poor formatting skills.

Good day community, I try to solve the 2D heat equation in cylindrical coordinates. I wanna follow a paper (Selim et al.: Temperature rise in a semi-infinite medium heated by a disc source) and therefor using a Laplace transform and a Hankel transform, subsequently, and there I encountered a problem.

I'll jump right in, my equation is:

eqn = D[T[r, z, t], {r, 2}] + 1/r D[T[r, z, t], r] + 
   D[T[r, z, t], {z, 2}] == 1/[Alpha] D[T[r, z, t], t]

lapl = LaplaceTransform[eqn,t,p] gives me a ,what I understand is a, correct result:

LaplaceTransform[(T^(0,2,0))[r,z,t],t,p]+LaplaceTransform[(T^(1,0,0))[r,z,t],t,p]/r+
LaplaceTransform[(T^(2,0,0))[r,z,t],t,p]==
(p LaplaceTransform[T[r,z,t],t,p]-T[r,z,0])/[Alpha]

However, when applying HankelTransform[lapl,r,s,0] the result I'm getting is:

HankelTransform[LaplaceTransform[(T^(0,2,0))[r,z,t],t,p],r,s,0]+
HankelTransform[LaplaceTransform[(T^(1,0,0))[r,z,t],t,p]/r,r,s,0]+
HankelTransform[LaplaceTransform[(T^(2,0,0))[r,z,t],t,p],r,s,0]==
(1/[Alpha])(p HankelTransform[LaplaceTransform[T[r,z,t],t,p],r,s,0]-
HankelTransform[T[r,z,0],r,s,0])`

while, based on the paper, I'm supposed to get:

$$\frac{\mathrm d^2 \overline{T_0}}{\mathrm dz^2}-\left(s^2+\frac{p}{\alpha}\right)\overline{T_0}=0$$

(In case the output is to tiring to read, as summary: there is no occurrence of s whatsoever, which makes doubt the correctness.)

Do I use the functions in wrong way (which I suppose is more likely) or is Mathematica (11.2) not able to transform this kind of input. Thanks in advance and forgive me my poor formatting skills.

added 85 characters in body
Source Link

Good day community, I try to solve the 2D heat equation in cylindrical coordinates. I wanna follow a paper (Selim et al.: Temperature rise in a semi-infinite medium heated by a disc source) and therefor using a Laplace transform and a Hankel transform, subsequently, and there I encountered a problem.

I'll jump right in, my equation is:

eqn = D[T[r, z, t], {r, 2}] + 1/r D[T[r, z, t], r] + 
   D[T[r, z, t], {z, 2}] == 1/[Alpha] D[T[r, z, t], t]

lapl = LaplaceTransform[eqn,t,p] gives me a what,what I understand is a, correct result:

LaplaceTransform[(T^(0,2,0))[r,z,t],t,p]+LaplaceTransform[(T^(1,0,0))[r,z,t],t,p]/r+
LaplaceTransform[(T^(2,0,0))[r,z,t],t,p]==
(p LaplaceTransform[T[r,z,t],t,p]-T[r,z,0])/[Alpha]

However, when applying HankelTransform[lapl,r,s,0] the result I'm getting is:

HankelTransform[LaplaceTransform[(T^(0,2,0))[r,z,t],t,p],r,s,0]+
HankelTransform[LaplaceTransform[(T^(1,0,0))[r,z,t],t,p]/r,r,s,0]+
HankelTransform[LaplaceTransform[(T^(2,0,0))[r,z,t],t,p],r,s,0]==
(1/[Alpha])(p HankelTransform[LaplaceTransform[T[r,z,t],t,p],r,s,0]-
HankelTransform[T[r,z,0],r,s,0])`

while, based on the paper, I'm supposed to get:

$$\frac{\mathrm d^2 \overline{T_0}}{\mathrm dz^2}-\left(s^2+\frac{p}{\alpha}\right)\overline{T_0}=0$$

(In case the output is to tiring to read, as summary: there is no occurrence of s whatsoever, which makes doubt the correctness.)

Do I use the functions in wrong way (which I suppose is more likely) or is Mathematica (11.2) not able to transform this kind of input. Thanks in advance and forgive me my poor formatting skills.

Good day community, I try to solve the 2D heat equation in cylindrical coordinates. I wanna follow a paper and therefor using a Laplace transform and a Hankel transform, subsequently, and there I encountered a problem.

I'll jump right in, my equation is:

eqn = D[T[r, z, t], {r, 2}] + 1/r D[T[r, z, t], r] + 
   D[T[r, z, t], {z, 2}] == 1/[Alpha] D[T[r, z, t], t]

lapl = LaplaceTransform[eqn,t,p] gives me a what I understand is a correct result:

LaplaceTransform[(T^(0,2,0))[r,z,t],t,p]+LaplaceTransform[(T^(1,0,0))[r,z,t],t,p]/r+
LaplaceTransform[(T^(2,0,0))[r,z,t],t,p]==
(p LaplaceTransform[T[r,z,t],t,p]-T[r,z,0])/[Alpha]

However, when applying HankelTransform[lapl,r,s,0] the result I'm getting is:

HankelTransform[LaplaceTransform[(T^(0,2,0))[r,z,t],t,p],r,s,0]+
HankelTransform[LaplaceTransform[(T^(1,0,0))[r,z,t],t,p]/r,r,s,0]+
HankelTransform[LaplaceTransform[(T^(2,0,0))[r,z,t],t,p],r,s,0]==
(1/[Alpha])(p HankelTransform[LaplaceTransform[T[r,z,t],t,p],r,s,0]-
HankelTransform[T[r,z,0],r,s,0])`

while, based on the paper, I'm supposed to get:

$$\frac{\mathrm d^2 \overline{T_0}}{\mathrm dz^2}-\left(s^2+\frac{p}{\alpha}\right)\overline{T_0}=0$$

(In case the output is to tiring to read, as summary: there is no occurrence of s whatsoever, which makes doubt the correctness.)

Do I use the functions in wrong way (which I suppose is more likely) or is Mathematica (11.2) not able to transform this kind of input. Thanks in advance and forgive me my poor formatting skills.

Good day community, I try to solve the 2D heat equation in cylindrical coordinates. I wanna follow a paper (Selim et al.: Temperature rise in a semi-infinite medium heated by a disc source) and therefor using a Laplace transform and a Hankel transform, subsequently, and there I encountered a problem.

I'll jump right in, my equation is:

eqn = D[T[r, z, t], {r, 2}] + 1/r D[T[r, z, t], r] + 
   D[T[r, z, t], {z, 2}] == 1/[Alpha] D[T[r, z, t], t]

lapl = LaplaceTransform[eqn,t,p] gives me a ,what I understand is a, correct result:

LaplaceTransform[(T^(0,2,0))[r,z,t],t,p]+LaplaceTransform[(T^(1,0,0))[r,z,t],t,p]/r+
LaplaceTransform[(T^(2,0,0))[r,z,t],t,p]==
(p LaplaceTransform[T[r,z,t],t,p]-T[r,z,0])/[Alpha]

However, when applying HankelTransform[lapl,r,s,0] the result I'm getting is:

HankelTransform[LaplaceTransform[(T^(0,2,0))[r,z,t],t,p],r,s,0]+
HankelTransform[LaplaceTransform[(T^(1,0,0))[r,z,t],t,p]/r,r,s,0]+
HankelTransform[LaplaceTransform[(T^(2,0,0))[r,z,t],t,p],r,s,0]==
(1/[Alpha])(p HankelTransform[LaplaceTransform[T[r,z,t],t,p],r,s,0]-
HankelTransform[T[r,z,0],r,s,0])`

while, based on the paper, I'm supposed to get:

$$\frac{\mathrm d^2 \overline{T_0}}{\mathrm dz^2}-\left(s^2+\frac{p}{\alpha}\right)\overline{T_0}=0$$

(In case the output is to tiring to read, as summary: there is no occurrence of s whatsoever, which makes doubt the correctness.)

Do I use the functions in wrong way (which I suppose is more likely) or is Mathematica (11.2) not able to transform this kind of input. Thanks in advance and forgive me my poor formatting skills.

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