Ammonia Rankine cycle heat engine calculation

• Biodelta
In summary, the conversation discussed the use of ammonia as a working fluid in a Rankine Cycle heat engine. The turbine entry temperature was set at 25 Bar and 60 degrees Celsius, with an outlet pressure of 4 Bar. The question was posed about the outlet temperature and the necessary mass flow rate of ammonia for an output power of 6 Gigawatt. The solution was provided in a PDF attachment, but further discussion revealed the need for access to thermodynamic tables or a pressure-enthalpy diagram for ammonia. The conversation also touched on the possibility of paying for a professional opinion.
Biodelta
Homework Statement
A Rankine Cycle heat engine uses ammonia as a working fluid, turbine entry temperature is 25 Bar at 60 degrees Celsius.

The turbine outlet pressure is 4 Bar, the question is: what is the outlet temperature? and if the output power is 6 Gigawatt (6x10^9 watt) what would the mass flow rate of the ammonia need to be for 6 Gigawatt? output
Relevant Equations
U = Q-W
A Rankine Cycle heat engine uses ammonia as a working fluid, turbine entry temperature is 25 Bar at 60 degrees Celsius.

The turbine outlet pressure is 4 Bar, the question is: what is the outlet temperature? and if the output power is 6 Gigawatt (6x10^9 watt) what would the mass flow rate of the ammonia need to be for 6 Gigawatt? output

What are your thoughts on this so far? What other information/data do you have available? Do you really feel that the Relevant Equation that you listed is the correct one to use?

My first approach to solving this has been to use: H'mmm cut and paste from word does not work, I will create a PDF and send that, Regards Stuart, back in a few hours

Hello, Attached is my solution which I am looking for confirmation of, it is in PDF attachment.
Thanks for considering this matter.
Regards
Stuart

Attachments

• Physics Forum Question.pdf
163.2 KB · Views: 240
Did you not have access to thermodynamic tables on ammonia (analogous to the steam tables) or to a pressure-enthalpy diagram for ammonia like this one: http://industrialheatpumps.nl/en/how_it_works/thermodynamic_cycle/

Thanks for that, I am a 67 year old retiree / inventor, and just wanted to get a few questions answered, I am not a student except for a few ideas I have. So my real question is how did the calculation stack up? is it valid? I am just looking at plug and play for this. I am also prepared to pay for a professional opinion.
Cheers
Stuart

Biodelta said:
Thanks for that, I am a 67 year old retiree / inventor, and just wanted to get a few questions answered, I am not a student except for a few ideas I have. So my real question is how did the calculation stack up? is it valid? I am just looking at plug and play for this. I am also prepared to pay for a professional opinion.
Cheers
Stuart
The p-H diagram shows that some of the ammonia will condense in the turbine. So your analysis is not correct. You can get your answer however using the p-H diagram.

1. What is an Ammonia Rankine cycle heat engine?

An Ammonia Rankine cycle heat engine is a type of heat engine that uses ammonia as the working fluid. It operates on the Rankine cycle, which is a thermodynamic cycle that converts heat into mechanical work. The ammonia Rankine cycle heat engine is commonly used in power generation systems.

2. How does the Ammonia Rankine cycle heat engine work?

The Ammonia Rankine cycle heat engine works by using ammonia as the working fluid. The ammonia is heated in a boiler, producing high-pressure steam. The steam then enters a turbine, where it expands and produces mechanical work. The remaining steam is condensed back into liquid form in a condenser, and the cycle repeats.

3. What factors affect the efficiency of the Ammonia Rankine cycle heat engine?

The efficiency of the Ammonia Rankine cycle heat engine is affected by various factors, including the temperature and pressure of the steam, the type of turbine used, and the efficiency of the condenser. Higher temperatures and pressures generally result in higher efficiency, while a more efficient turbine and condenser can also improve efficiency.

4. How is the efficiency of the Ammonia Rankine cycle heat engine calculated?

The efficiency of the Ammonia Rankine cycle heat engine is calculated by dividing the net work output by the heat input. This can be expressed as a percentage and is known as the thermal efficiency. The formula for calculating thermal efficiency is (W/Qin) x 100, where W is the net work output and Qin is the heat input.

5. What are the applications of the Ammonia Rankine cycle heat engine?

The Ammonia Rankine cycle heat engine has various applications, including power generation, waste heat recovery, and geothermal power plants. It is also used in industries such as chemical, petrochemical, and food processing for heating and cooling processes. Additionally, it can be used in refrigeration systems as a more environmentally friendly alternative to traditional refrigerants.

• Thermodynamics
Replies
5
Views
711
• Engineering and Comp Sci Homework Help
Replies
4
Views
1K
• Engineering and Comp Sci Homework Help
Replies
1
Views
856
• Engineering and Comp Sci Homework Help
Replies
1
Views
699
• Materials and Chemical Engineering
Replies
18
Views
3K
• General Engineering
Replies
2
Views
1K
Replies
1
Views
2K
• Mechanical Engineering
Replies
10
Views
2K
• Introductory Physics Homework Help
Replies
2
Views
1K
• Mechanical Engineering
Replies
2
Views
3K