Thermodinamics II
Science
Complete problem solution using Tables and EES. Solve (a) through (c) by hand using tables. Then solve with EES, including (d). No separate setup for EES is required. Consider a steam power plant that operates on a simple Rankine cycle and has a net power output of 45 MW. The plant is modeled as an ideal system, except the turbine has the isentropic efficiency of 94%. Steam enters the turbine at 7 MPa and 500°C and is cooled in the condenser at a pressure of 10 kPa by running cooling water from a lake through the tubes of the condenser at a rate of 2000 kg/s (this is not a part of the Rankine cycle itself, but only the cooling water for the condenser). Assignment: First sketch the system hardware diagram (including the cooling water), number states and show the cycle on a T-s diagram with respect to saturation lines (only 4 states for the steam, no cooling water). Then determine (a) the thermal efficiency of the cycle, (b) the mass flow rate of the steam, and (c) the temperature rise of the cooling water. Note that the steam and the cooling water in the condenser do not mix. (d) Create a plot which shows the effect of the turbine’s isentropic efficiency (in the range 0.1 to 1) on the three calculated answers (a) through (c) above.
