[immortality]

I have found the cause of errors in my simulation.its at scavenging process.
there is a tube that is filled with
internalField: U=0,T=400K,p=250000pa
and suddenly one side of it become open to environment.the environment has

BC: p0=100000pa and T=288K.
I have set various set of BC's for it but I have not obtain correct answer yet.a divergence in e calculation is occured because of decreasing T below 200K.
I have examined these sets so far:
1)p:waveTransmissive T and U:zeroGradient

type            waveTransmissive;
        field           p;
        phi             phi;
        rho             rho;
        psi             psi;
        gamma           1.4;
        fieldInf        100000;
        lInf            .1;
        value           uniform 100000;

problem: physically incorrect situation with continously increasing pressure return of decreasing.
2)p:totalPressure T and U:zeroGradient

type totalPressure;
            p0 uniform 100000;
            gamma 1.4;
            rho rho;
            psi none;

problem: physically incorrect situation with reaching high pressure around 200000 return of outside pressure(100000).
3)p:fixedValue T and U:zeroGradient

type fixedValue;
      value uniform 100000;

problem: physically incorrect situation with a very low temperature and divergence due to e value.
4)p:fixedValue T:fixedValue U:zeroGradient
T:

type fixedValue;
      value uniform 288;

p:

type fixedValue;
      value uniform 100000;

problem:like above(3)
why this simple phenomenon has these difficulties?
could anyone give me any help?
thanks.