First Law of Thermodynamics help

[lecammm]

Homework Statement

Steam flow through a pipe at a pressure if 8bar and a temperature of 340C. A valve is opened and steam is allow to enter an insulated enclosure whose volume is 0.5(m^3), until the pressure equals the quantity of steam that enters the enclosure.

Homework Equations

Q - W + ∑M_IN(h_IN+(v²_IN)/2+gz_IN) - ∑m_OUT(h_OUT+(v²_OUT)/2+gz_OUT) = m₂(u₂+(v²₂)/2+gz₂) - m₁(u₁+(v²₁)/2+gz₁)

The Attempt at a Solution

(Here is where I'm not sure)

I know that:

gz = 0 for all

And I would have thought that because up until the pressure in the chamber is equivalent to the mass of the steam, m_OUT would be zero, as the steam is only coming in.

I also THINK that Q is 0 because no heat is being added to the system, and W is zero because there is no mechanical reactions.

However, what I don't understand is the answer says that m₁ is 0 (why? Is this because the only input is m_IN?), v_IN is 0 (is this because of the equivalence of v₁ and v_IN?)

The next step in the solution is

m_INh_IN = m₂u₂

And is it right that m_IN and m₂ will be equivalent based of continuity?

Thanks for any help as I am alright with using steam tables and interpolation later

 

[maajdl]

There is no question in the problem statement.
In your relevant equation, I observed two different kind of indices:

IN and OUT
1 and 2

What does that all mean?
An equation without meaning is useless.

Do not expect to solve a problem that you cannot expose properly, or that you do not understand.