Heating a Heat Engine - Efficiency Calculation

Click For Summary
To measure the efficiency of a heat engine, it's crucial to accurately determine the input energy. Measuring the temperature of the heat engine can provide insights into the heat input, but calorimetry may offer a more precise method. It's important to decide whether to maintain a constant temperature or a constant heat energy input; both approaches have implications for efficiency calculations. The usable energy from the heat engine is linked to the temperature difference between the heat source and the heat sink. Understanding these factors is essential for comparing mechanical output to heat input effectively.
Tawaffles
Messages
7
Reaction score
0
Hi.

Im trying to measure the efficiency of a heat engine. I therefore need to work out what the input energy is to the heat engine.

I have two problems. Firstly, how should I measure the heat going into the stirling rather than the heat coming out of the heater. Is it ok to measure the temperature of the heat engine as an indication of the heat input energy?

Secondly, should I be trying to put in a contstant temperature, or constant heat energy? So, should I be saying, I need my heater to keep it at 18C or should I say, I need to be putting 5KW into into constantly?

Im trying to compare the mechanical output to the heat input.

James
 
Science news on Phys.org
Maybe try something with calorimetry.
 
The actual amount of usable energy you should be able to use with a heat engine should be the related to the difference in temperature between your heat source and your heat sink.
 
Thread 'Can somebody explain this: Planck's Law in action'

Thread 'Can somebody explain this: Planck's Law in action'

Plotted is the Irradiance over Wavelength. Please check for logarithmic scaling. As you can see, there are 4 curves. Blue AM 0 as measured yellow Planck for 5777 K green Planck for, 5777 K after free space expansion red Planck for 1.000.000 K To me the idea of a gamma-Ray-source on earth, below the magnetic field, which protects life on earth from solar radiation, in an intensity, which is way way way outer hand, makes no sense to me. If they really get these high temperatures realized in...
View full post »

Similar threads

High School Heat pump as a heat engine that operates in reverse
  • · Replies 19 ·
Replies
19
Views
4K
High School Can a Heat Pump and Stirling Engine Create a Perpetual Energy Cycle?
  • · Replies 6 ·
Replies
6
Views
3K
High School Lorenz COP of a heat pump and the temperatures of the hot/cold reservoirs
  • · Replies 3 ·
Replies
3
Views
3K
Should ice take longer to melt when used to run a heat engine?
  • · Replies 87 ·
3
Replies
87
Views
8K
Graduate Practical use of an overall heat transfer coefficient?
  • · Replies 14 ·
Replies
14
Views
3K
Undergrad Interseasonal heat storage / sand battery insulation?
  • · Replies 27 ·
Replies
27
Views
5K
Graduate Calculating the heat loss of an open water tank (aquarium)
  • · Replies 2 ·
Replies
2
Views
3K
Does a good heat engine make a bad refrigerator?
  • · Replies 6 ·
Replies
6
Views
13K
Thermodynamic sign convention for heat (i.e. in heat engines)
  • · Replies 11 ·
Replies
11
Views
4K
Temperatures of the hot source and cold sink in a heat engine
  • · Replies 2 ·
Replies
2
Views
3K