Author: haroonkhan

First law of thermodynamics does not tell about the following:

In some flow process, mass flow rate is not steady but varies with respect to time. In such a case, the difference in energy flow is stored in system as ΔEv. Rate of energy increase = Rate of energy inflow − Rate of energy outflow Example 1.14: An air conditioning system, as shown in Figure 1.8, handling 1…

Steady Flow Process In a steady flow process, thermodynamic properties at any section remain constant with respect to time; it can vary only with respect to space. A schematic diagram of steady flow process is shown in Figure 1.7. Figure 1.7 Schematic Diagram of Steady Flow Process From continuity equation: Energy balance equation: This is known as…

In this process, the law is governed by PVn = constant. Work done during adiabatic process From first law of thermodynamics Example 1.2: The initial pressure and temperature of 1 mole of an ideal gas are 1 MPa and 380 K, respectively. It is heated at constant pressure till the temperature is doubled and then is allowed to expand…

In this process, heat transfer is equal to zero. Work done during adiabatic process From first law of thermodynamics

In this process, temperature remains constant, i.e., ΔT = 0. This is also known as isothermal process. From first law of thermodynamics

In this process, pressure remains constant, i.e., Δp = 0. This is also known as isobaric process. The work done from state 1 to state 2.   W = pdV = p(V1 − V2)   From first law of thermodynamics

In this process, volume remains constant, i.e., ΔV = 0. This is also known as isochoric process. From first law of thermodynamics:

The various non-flow processes and their characteristics are shown in Figure 1.3. Figure 1.3 Non-flow Processes

Heat and work are energy transfer mechanisms between a system and its surroundings. Some of the similarities between heat and work are as follows: