Is This Civil Engineering PDE Linear?

In summary, the conversation is about a linear partial differential equation that represents the equation of motion for frame members in civil engineering. The equation includes variables such as EI, N, and m, and cannot be analytically solved due to its complexity. The best approach to solving it would be through numerical calculus. The conversation also touches on the importance of making questions clear and easy to read when seeking help on forums.
  • #1
omarxx84
28
0
can anyone help me to solve this equation ?. is this equation linear or not?
knowing, this equation represents the equation of motion for frame members for materials which have different moduli in tension and compression (civil engineering).
"EI" ("x,t" ) ("∂" ^"4" "u" ("x,t" ))/〖"∂x" 〗^"4" "-N" ("x" ) ("∂" ^"2" "u" ("x,t" ))/〖"∂x" 〗^"2" "+m" ("x,t" ) ("∂" ^"2" "u" ("x,t" ))/〖"∂t" 〗^"2" "=0"
In which,
EI depends on a roots of cubic equation, and t depends on ("∂" ^"2" "u" )/〖"∂t" 〗^"2" (acceleration)
boundary conditions:
at x=0, u=0 and at x=L, u=0
at t=0, u=0
 
Last edited:
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  • #2
That's too messy to read. Go to the "Math and Science Learning Material" sub-forum above, and look at "Introducing LaTex typesetting thread to see about formatting math for the forum. For example:

[tex]\frac{\partial u}{\partial t}=\frac{\partial^2 u}{\partial x^2}[/tex]

Click on the equation to see the code used to generate it.
 
  • #3
EI(x,t) (∂^4 u(x,t))/〖∂x〗^4 -N (∂^2 u(x,t))/〖∂x〗^2 +m(x,t) (∂^2 u(x,t))/〖∂t〗^2 =0
please, try to read, then help me to solve it.
 
  • #4
Yes, the PDE is linear.
Since EI(x,t) and m(x,t) are not explicit, the equation cannot be analitically solved.
Even if EI(x,t) and m(x,t) were explicit, but probably not simple formulas, the equation couldn't be analitically solved in the general case.
Probably, numerical calculus is the only way.
 
  • #5
omarxx84 said:
EI(x,t) (∂^4 u(x,t))/〖∂x〗^4 -N (∂^2 u(x,t))/〖∂x〗^2 +m(x,t) (∂^2 u(x,t))/〖∂t〗^2 =0
please, try to read, then help me to solve it.

i think when posting to a forum it is courteous to abide by their standards or requests. it reflects much better on you if you show that you've taken the time to make the question easier to read or more understandable, which will further add to people's willingness to help you.

replying to someone by saying no i won't work on making it easier to read, you should try harder, usually won't get you anywhere.
 
  • #6
what is the best books or papers for solving nonlinear integro-differential equations??
 
  • #7
please...What is the solution of the governing linear partial differential equation, with variable coefficients, of motion attached in the attached file. and i will be very grateful for you...
 

Attachments

  • The governing partial differential equation of motion for our case is.pdf
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FAQ: Is This Civil Engineering PDE Linear?

What is a partial differential equation (PDE)?

A partial differential equation is a mathematical equation that involves an unknown function of multiple independent variables and its partial derivatives. It is used to describe how a quantity changes over space and time.

What are some practical applications of PDEs?

PDEs have a wide range of applications in various fields such as physics, engineering, economics, and biology. They are used to model physical phenomena like heat transfer, fluid dynamics, and quantum mechanics. They are also used in financial mathematics to price options and in image processing to enhance images.

What is the difference between a PDE and an ordinary differential equation (ODE)?

A PDE involves partial derivatives, while an ODE involves only ordinary derivatives. This means that a PDE involves functions of multiple variables, whereas an ODE involves functions of a single variable.

How do you solve a PDE?

Solving a PDE involves finding a function that satisfies the equation and any given boundary conditions. This can be done analytically, using techniques such as separation of variables or the method of characteristics, or numerically using computer algorithms.

What are the different types of PDEs?

PDEs can be classified into elliptic, parabolic, and hyperbolic equations based on the behavior of their solutions. Elliptic equations have a smooth and continuous solution, while parabolic equations describe processes that evolve over time, and hyperbolic equations describe waves and oscillations.

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