Question

The following data were obtained in a test on a combined separating and throttling calorimeter : 

Pressure of steam sample = 15 bar, pressure of steam at exit = 1 bar, temperature of steam at the exit = 150°C, discharge from separating calorimeter = 0.5 kg/min, discharge from throttling calorimeter = 10 kg/min. 

Determine the dryness fraction of the sample steam

Answer 1

Pressure of steam sample, p₁ = p₂ = 15 bar 

Pressure of steam at the exit, p₃ = 1 bar 

Temperature of steam at the exit, t_sup3 = 150°C 

Discharge from separating calorimeter, m_w = 0.5 kg/min 

Discharge from throttling calorimeter, m_s = 10 kg/min 

From steam tables :

Now, quality of steam supplied,