z*h
发帖数: 773 | 1 Here thermal energy is from one temperature without any temperature gradient
. |
z*h
发帖数: 773 | 2 No one can answer it.
Now I can do it. Can I claim that I am the first person?
I have spent a lot of time on energy conversion survey and efficiency
analysis. I cannot find more examples against my results.
What I know now.
Mechanic energy --> Electricity (generator, 95%)
Electricity--> mechanic energy (motor, 80-95%)
Chemical energy --> Thermal energy (burning, 100%) --> mechanic energy heat
engine, 40-60%) --> electricity
Chemical energy --> electricity (fuel cell, 40-80%)
Electricity --> ther
【在 z*h 的大作中提到】
: Here thermal energy is from one temperature without any temperature gradient
: .
|
e****o
发帖数: 165 | 3
heat
【在 z*h 的大作中提到】
: No one can answer it.
: Now I can do it. Can I claim that I am the first person?
: I have spent a lot of time on energy conversion survey and efficiency
: analysis. I cannot find more examples against my results.
: What I know now.
: Mechanic energy --> Electricity (generator, 95%)
: Electricity--> mechanic energy (motor, 80-95%)
: Chemical energy --> Thermal energy (burning, 100%) --> mechanic energy heat
: engine, 40-60%) --> electricity
: Chemical energy --> electricity (fuel cell, 40-80%)
|
z*h
发帖数: 773 | 4 Is there an expert in thermodynamics and chemistry physics? |
n****t
发帖数: 729 | 5 热能转化效率的上限，根据热力学第二定律，不能超过卡诺效率。而根据卡诺定律，温
差为零的话，效率必然为零。所以你的设想违反热力学第二定律，不可能实现。
【在 z*h 的大作中提到】
: Is there an expert in thermodynamics and chemistry physics?
|
z*h
发帖数: 773 | 6 卡诺定律 is applied to conversion between mechanic energy and thermal energy
between two different temperature.
Now what I talk about is conversion between thermal energy (one temperature
by absorbing heat from environment) and chemical energy. |
n****t
发帖数: 729 | 7 虽然卡诺定理来源于热能转化为机械能效率的计算，但由于不同能量形式之间可以互相
转换，而在转换过程中能量守恒，卡诺定理给出的结论同样适用于热能向其它能量形式
的转化。
能够持续进行热能转换的装置都可以看作为一个“热机”。如果你的“化学热机”能够
持续地进行热能转换，这就是一个热力学上的可逆过程，根据热力学第二定律，它必须
工作在两个温度不同的热源之间，其转换效率不高于卡诺效率。在没有温度梯度的情况
下，就相当于它只从单一热源吸取热量而对外做功，其本质就是第二类永动机。
如果你的化学热机并不进行持续的能量转换，这不是一个可逆过程。在初始时刻，如果
你的化学热机和热源之间存在温差，它可以输出化学能。随着时间推移，化学热机和热
源必然达到热平衡，即两者温度相等。根据热力学第二定律的克劳修斯表述，化学热机
已经不能再从热源吸收热量，自然无法无中生有地创造出化学能来。
总结一下，无论是否可逆过程，温度梯度的存在都是热能转换能够进行的必要条件，而
且在温度相等的两个物体之间讨论热能是没有意义的。
energy
temperature
【在 z*h 的大作中提到】
: 卡诺定律 is applied to conversion between mechanic energy and thermal energy
: between two different temperature.
: Now what I talk about is conversion between thermal energy (one temperature
: by absorbing heat from environment) and chemical energy.
|
n****t
发帖数: 729 | 8 You said: "Electricity --> thermal (100%, or > 100% by heat pump)"
Your statement about the heat pump is very misleading.
The extra amount of thermal energy that makes seeming >100% efficiency comes
from the thermal energy transferred by the heat pump from the cold side to
the hot side of the heat pump. It is not the thermal energy transformed by
the heat pump from electrical enery.
Energy can be transferred from one object to another, or transformed from
one form to another, but can never be cr
【在 z*h 的大作中提到】
: No one can answer it.
: Now I can do it. Can I claim that I am the first person?
: I have spent a lot of time on energy conversion survey and efficiency
: analysis. I cannot find more examples against my results.
: What I know now.
: Mechanic energy --> Electricity (generator, 95%)
: Electricity--> mechanic energy (motor, 80-95%)
: Chemical energy --> Thermal energy (burning, 100%) --> mechanic energy heat
: engine, 40-60%) --> electricity
: Chemical energy --> electricity (fuel cell, 40-80%)
|
