Ministry of Education of the Republic of Azerbaijan Baku Engineering University Faculty: "Architecture and Construction". Department: "Architecture and Design". Course Title: Engineering communication systems of buildings

l  q₁  q₂ . (11)
This is a mathematical expression of the first law of thermodynamics for closed processes. Heat The thermal efficiency of the machine (FIA) is determined as follows:

Here q₂  q₁ because _t  1 is. Thus, it seems that hot and cold sources and a working body are needed to convert thermal energy into continuous work. If a cold environment is excluded from the circuit of the heating machine, the formal equivalence is not violated. However, analysis of the operation of the heat engine and experience show that such an engine can not work.
A heat engine without a cold environment, that is, an engine that completely converts heat from a hot environment, is called a type II permanent engine. Thus, the second law of thermodynamics can be expressed as follows: Type II permanent motor is not possible. The only result a periodic heating machine that converts heat from any environment is not possible.
It is important that heating machines have a high thermal FIE and the thermodynamics of which the value of the cycle at the same value of other conditions depends on the processes.

2. 
   CARNO CYCLE
   

Theoretically, when the heat engine runs on the Carnot cycle, more of the heat becomes work. The Carnot cycle consists of two adiabats (2-3 and 4-1) and two isotherms (1-2 and 3-4) consists of (Picure 1.21).
The work of the cycle is defined as follows:
l  q₁  q₂ (13)
here q₁ and q₂ -1 -2 and -3-4 in isothermal processes ( T_h  const and T₀  const ) are the cycles given and received from the cycle and are defined as follows:




Thermal FIE of the Carnot cycle:

Suitable for cyclin 2-3 and 4-1 adiabatic processes Tv^k1  const using the equation v3 / v4 = v2 / v1 you can get that.
Taking into account the last equation, if we make several transformations, the thermal FIE of the Carnot cycle can be determined as follows:



(17)
It turns out that the thermal FIE of the Carnot cycle depends only on the absolute temperatures of hot and cold sources. To increase the FIE of the Carnot cycle, either the temperature of the hot medium must be increased or the temperature of the cold medium must be reduced. As a result of the second law of thermodynamics, (17) reflects its essence. İn order to fully convert the heat from the hot environment, so _tk  1 for T₁  or T₂  0 conditions must be done. None of these conditions can be met. While T₁  T_{2 is} _tk  0. This shows that heat cannot be converted into work when the temperatures of the system's environments are the same, that is, when there is a heat equilibrium.

2.