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

Matlab, how i found largest cluster in percolation

how i found largest cluster in percolation

Fenrir chain, Fenrir the wolf is bound by a magical chain. The chain is an ...

Fenrir the wolf is bound by a magical chain. The chain is an endless piece madr up of 30 links.Originally forged by 6 pieces , each made up of 5 links. It costs 2 silver coins to c

How are Indian customers visiting Shoppers’ Stop any differe, How are India...

How are Indian customers visiting Shoppers’ Stop any different from customers of developed western countries?

Design a game strategy involves process of learning maths, Doing these sums...

Doing these sums initially in this way helps children see why they carry over numbers to the next column. You may like to devise some related activities now. , EI) Give activ

Evaluate integrals, Evaluate following integrals.  (a) ∫ 3e x + 5 cos x...

Evaluate following integrals.  (a) ∫ 3e x + 5 cos x -10 sec 2   x dx  (b) ( 23/ (y 2 + 1) + 6 csc y cot y + 9/ y dy Solution (a)    ∫ 3e x + 5 cos x -10 sec 2 x

Conduct an appropriate hypothesis test, Aspire LLP is a recruitment agency....

Aspire LLP is a recruitment agency. Recently, the company senior manager, Kay conducted a survey to understand the number of hours students spend daily on their studies after schoo

Applications of de moiver, what are the applications of de moiver''s theore...

what are the applications of de moiver''s theorem in programming and software engineering

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