Abt. Ghost Fluid Method in one-dim.

jinwon

I am studying about the GFM for my reserach work. To do it, I bought Fedkiw's book and read all his papers. In doing it, I am stuck with the ghost cell. As mentioned in his book, I implemented the procedure for GFM to solve the problem which two phase gases(gamma=1.4 and 1.6) exist but I couldn't obtain a desirable solution. But I obtained reasonable solutions(w/ sharper interface than standard method) for single phase gas problem w/ GFM. My procedures are absolutely followed by his book.

Let me explain briefly. First, find the interface location using the level set function Second, compute the entropy at the real fluid part entropy=p/density**gamma Third, obtain the density based on the isentropic assumption, density=(p/entropy)**(1.0/gamma) Fourth, update the conservative variables using recomputed density above

I did all directed in his book and references but I couldn't desirable interface location and continuous variable at there.

Please let me know what I misunderstood.

Step 1. Find the interface location based on the level function

int=i-1 when the interface lies between cell i and i-1

!----------------------

! GHOST FLUID METHOD !

!----------------------

Step 2. Compute the entropy at cell i-1 with gamma1=1.4

ent1=p(int-1)/rho(int-1)**gamma1 <- Isentropic assumption

!

!-----> EXTRAPOLATING of ENTROPY TO FIND THE DENSITY

Step 3. Extrapolate the density at cell i w/ gamma2=1.6

rho(i)=(p(int)/ent1)**(1.d0/gamma2)

!

Step 4. Update the conservative variable

m=rho(int)*v(int)

e=p/(gamma2-1.d0)+0.5*rho(int)*v(int)*v(int)

!

! For int w/ int+1

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