1. The total enthalpy of 15.000kg of steam at 2250.000kPa is 34191.510kJ. Determine the dryness of the steam.
ANS = %
2. Determine the quantity of heat required, to raise 11.100kg of water at 80.000 degrees Celsius, to saturated steam at 2250.000kPa and 71.400% dry.
ANS = kJ
Not sure where to start. I need a little help please. I do have a chart with the properties of saturated steam. Thank you.
To determine the dryness of steam and the quantity of heat required in these two questions, you will need to use steam tables or the properties of saturated steam chart.
1. To determine the dryness of the steam:
- Look up the specific enthalpy value for saturated steam at 2250.000kPa in the steam tables or chart.
- The specific enthalpy value for saturated steam will give you the enthalpy of the wet steam (steam with some liquid water content).
- Subtract the enthalpy of the wet steam from the total enthalpy given in the question.
- Divide the difference by the enthalpy of dry saturated steam at the same pressure to get the dryness fraction.
- Multiply the dryness fraction by 100 to get the percentage.
2. To determine the quantity of heat required:
- Determine the enthalpy of water at 80.000 degrees Celsius using the properties of water table.
- Find the enthalpy of dry saturated steam at 2250.000kPa and 71.400% dry in the steam tables or chart.
- Calculate the difference between the enthalpy of steam and the enthalpy of water to determine the heat required.
- Multiply the heat required by the mass of water to get the total quantity of heat required.
By following these steps and using the given data from the steam tables or chart, you should be able to arrive at the answers.