Where did I go wrong? Seeking expert help to solve thermodynamics calculations—related to adiabatic enthalpy drop, steam consumption rate, and turbine shaft power.

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Was I wrong? Where did I go wrong? I’m seeking help from experts to resolve the main issues in the thermodynamics calculations. Please download the attachment. For the steam conditions, the inlet steam pressure is 1.6 MPa at 285 degrees Celsius, while the exhaust steam pressure is 0.42 MPa at 234 degrees Celsius. The adiabatic specific enthalpy values for these conditions were obtained as follows. The adiabatic enthalpy drop can be calculated as 3002.098 – 2930.66 = 71.438 kJ/kg. According to standard formulas, the relationship between flow rate, power, and enthalpy drop is given by: N = 150 kW. Here, G is the value we need to determine, with units of kg/h; Δhs represents the adiabatic enthalpy drop, with units of kJ/kg. As mentioned earlier, Δhs = 3002.098 – 2930.66 = 71.438 kJ/kg. η represents the internal efficiency, which for medium-pressure steam turbines is typically taken as 0.7. Therefore, 1500 = G * 71.438 * 0.7 / 3600, which gives G = 10798.5746 kg/h. The units and calculations have been checked repeatedly, and no errors were found. There’s also a constant: 1 kW = 3600 kJ/h. Using this, G can be calculated as 150 * 3600 / 50.0066 = 10798.5746. Thus, G equals 10798.5746 kg/h, or 10.798 tons/h. This value of 10.798 tons/h differs significantly from the steam flow rate of 6.5 tons/h listed in Table 3. Why is that? Which step did I get wrong? ? Below are the formulas from another book; if the steam parameters and specific enthalpy are substituted into these formulas, the calculated values differ even more significantly from those listed in Table 3. So, how exactly should the steam volume, steam consumption rate, and shaft power be calculated? Can this be explained by error? ? Where did I make a calculation mistake? If I use the formula in the figure below, how should I calculate the steam volume, steam consumption rate, and shaft power based on the steam parameters? Please list the verification steps, thank you!