Thermodynamics question - is this right?

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The discussion revolves around calculating the temperature increase of river water downstream from a power plant operating as an ideal Carnot engine. The power plant generates 980 MW, with steam entering the turbine at 625 K and depositing heat into river water at 285 K. The calculations indicate an efficiency of 0.544, leading to a heat output of 980 MJ/s. The flow rate of the river is 37 m³/s, resulting in a temperature increase of approximately 6.327 degrees Celsius. Additionally, the discussion touches on the heat drawn from the hot reservoir and the heat rejected to the cold reservoir, emphasizing the relationship between work output and heat transfer.
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Suppose a power plant delivers energy at 980 MW using steam turbines. The steam goes into the turbine superheated at 625 K and deposits its unused heat in river water at 285 K. Assume that the turbine operates as an ideal Carnot engine. If the river flow rate is 37 m^3 / s, estimate the average temperature increase of the river water immediately downstream from the power plant. What is the entropy increase per kilogram of the downstream river water in J / kg * K?


What I've got so far, is this right?:

e ideal = [ Th - Tl ] / Th = [625 - 285] / 625 = .544 (don't know if this has any relevance in the question being asked)

density of water - 1000 kg / m^3

flow of 37 m^3 / s times 1000 kg / m^3 = 37,000 kg / s

980 MW = 980 MJ / s = 980000 kJ

980 MW = flow (kg/s) * heat capacity (kJ / kg / degrees Celsius) * T (degrees Celsius)

T = [980000 / (37000 * 4.186)] = 6.327 degrees Celsius ?
 
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N_L_ said:
Suppose a power plant delivers energy at 980 MW using steam turbines. The steam goes into the turbine superheated at 625 K and deposits its unused heat in river water at 285 K. Assume that the turbine operates as an ideal Carnot engine. If the river flow rate is 37 m^3 / s, estimate the average temperature increase of the river water immediately downstream from the power plant. What is the entropy increase per kilogram of the downstream river water in J / kg * K?


What I've got so far, is this right?:

e ideal = [ Th - Tl ] / Th = [625 - 285] / 625 = .544 (don't know if this has any relevance in the question being asked)

density of water - 1000 kg / m^3

flow of 37 m^3 / s times 1000 kg / m^3 = 37,000 kg / s

980 MW = 980 MJ / s = 980000 kJ

980 MW = flow (kg/s) * heat capacity (kJ / kg / degrees Celsius) * T (degrees Celsius)

T = [980000 / (37000 * 4.186)] = 6.327 degrees Celsius ?
The efficiency is .544 and the work output/unit time is 980 mW. So how much heat is drawn from the hot reservoir and how much is rejected to the cold reservoir? Use:

Q_h - Q_c = W and

\eta = W/Q_h

AM
 
Thank you.
 
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