differential equation, Mathematics

Assignment Help:
Suppose a fluid (say, water) occupies a domain D? R^(3 ) and has velocity field V=V(x, t). A substance (say, a day) is suspended into the fluid and will be transported by the fluid as well as diffused within it; let u= u(x,t) be the concentration of the substance( mass per unit volume). Let Ø= Ø(x,t) be the concentration flux (mass per unit area per unit time, analogous to heat flux). Let B(x) be a ball of radius r > 0 contained in D. Derive the conservation law.

?_(B (x))¦u_(t ) dV= -?_(? B(x))¦?Ø.n_0 dS.?

Fick''s law for diffusion states that the concentration flux due to diffusion is proportional to the gradient of the concentration flux due to diffusion is proportional to the gradient of the concentration. Deduce that Ø= -k?+uV.
Apply the divergence theorem to the conservation law and substitute the flux formula to arrive at the diffusion- transport equation:
u_t= ?.(k?u)+ ?.(uV).
in the absence of diffusion (k=0), this is the higher- dimensional transport equation. If the fluid is motionless, it is called the diffusion equation.
Suppose a fluid (say, water) occupies a domain D? R^(3 ) and has velocity field V=V(x, t). A substance (say, a day) is suspended into the fluid and will be transported by the fluid as well as diffused within it; let u= u(x,t) be the concentration of the substance( mass per unit volume). Let Ø= Ø(x,t) be the concentration flux (mass per unit area per unit time, analogous to heat flux). Let B(x) be a ball of radius r > 0 contained in D. Derive the conservation law.

?_(B (x))¦u_(t ) dV= -?_(? B(x))¦?Ø.n_0 dS.?

Fick''s law for diffusion states that the concentration flux due to diffusion is proportional to the gradient of the concentration flux due to diffusion is proportional to the gradient of the concentration. Deduce that Ø= -k?+uV.
Apply the divergence theorem to the conservation law and substitute the flux formula to arrive at the diffusion- transport equation:
u_t= ?.(k?u)+ ?.(uV).
in the absence of diffusion (k=0), this is the higher- dimensional transport equation. If the fluid is motionless, it is called the diffusion equation.

Related Discussions:- differential equation

Equal matrices - linear algebra and matrices, I need assignment help for Eq...

I need assignment help for Equal Matrices. can you please define Equal Matrices?

Math, a business is owned by three people.the first owns 1/12 of the busine...

a business is owned by three people.the first owns 1/12 of the business and the second owns 1/6 of the business. what fractional part of the business is owned by the third person

Alternating series test - sequences and series, Alternating Series Test - S...

Alternating Series Test - Sequences and Series The final two tests that we looked at for series convergence has needed that all the terms in the series be positive.  Actually t

Applications of derivatives rate change, Application of rate change Bri...

Application of rate change Brief set of examples concentrating on the rate of change application of derivatives is given in this section.  Example    Find out all the point

Factoring trinomial, what is the factor of the trinomial 2x2-7x-4

what is the factor of the trinomial 2x2-7x-4

Personal assistance needed, I have an original finding on the subject of pr...

I have an original finding on the subject of prime distribution and would like expert help in my endeavors. I have written a paper describing everything in detail and demonstration

Equivalence relation, a) Let V = f1, 2, :::, 7g and define R on V by xRy if...

a) Let V = f1, 2, :::, 7g and define R on V by xRy iff x -  y is a multiple of 3. You should know by now that R is an equivalence relation on V . Suppose that this is so. Explain t

The prerequisites for multiplication, THE PREREQUISITES FOR MULTIPLICATION ...

THE PREREQUISITES FOR MULTIPLICATION : The word 'multiply', used in ordinary language, bears the meaning 'increase enormously For instance, bacteria multiply in favourable conditi

Functions of many variables, There may be more than one independent v...

There may be more than one independent variable which determines the value of y. The dimension of a function is determined by the number of independent variables in the

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd