Tds = dh - vdp
For a simple compressible substance of fixed composition, \(T\,ds=du+p\,dv\) and \(h=u+pv\). Differentiating h gives \(dh=du+p\,dv+v\,dp\), hence \(T\,ds=dh-v\,dp\). This property relation underlies the h–s (Mollier) diagram.
Important Questions from Phase Change of a Pure Substance
- Which of the following exists in a P-V diagram for water?
What the region (2) in the p-V diagram given below is called?
The saturation temperature of steam with increase in pressure increases _________.
A rigid tank contains 10 kg of water at 90°C. If 8 kg of water is in liquid form and the rest is in vapour form, what will be the volume of the tank?
[Given: At 90°C, saturation pressure is 70 kPa , specific volume at saturated liquid state = 0.001 m3/kg , specific volume at saturated vapour state = 2.36 m3/kg.]
- The triple point on a T-s diagram is _________.
