Author: workhouse123

Proximate analysis indicates the percentage by weight of the fixed carbon, volatiles, ash, and moisture content in coal. The amounts of fixed carbon and volatile combustible matter directly contribute to the heating value of coal. Fixed carbon acts as a main heat generator. High volatile matter content indicates easy ignition of fuel. The ash content…

The ultimate analysis indicates the various chemical constituents such as carbon, hydrogen, oxygen, sulphur, etc. It is useful in determining the quantity of air required for combustion and the volume and composition of the combustion gases. This information is required for the calculation of flame temperature and the flue duct design, etc.

There are two methods for coal analysis—ultimate and proximate analysis. The ultimate analysis determines all solid or gaseous coal components, and the proximate analysis determines only the percentage of carbon, volatile matter, moisture, and ash.

Any material that can be burned to release thermal energy is called a fuel. Most familiar fuels consist primarily of hydrogen and carbon, called hydrocarbon fuels. Hydrocarbon fuels exist in all phases; some examples are coal, gasoline, and natural gas. Fuels are the materials which ignite in presence of oxygen and produce heat. The heat…

Third law of thermodynamics is law of entropy. It is a statement about the ability to create an absolute temperature scale, for which absolute zero is the point at which the internal energy of a solid is zero. Third law of thermodynamics states that it is impossible to reduce any system to absolute zero in…

 Entropy Defining entropy in an exact word or line is impossible. It can be viewed as a measure of molecular disorder or molecular randomness. As a system becomes more disordered, the positions of the molecules become less predictable and the entropy increases. Thus, the entropy of a substance is lowest in the solid phase and…

The efficiency of a heat engine cycle greatly depends on how the individual processes are executed. The net work can be maximized by using reversible processes. The best known reversible cycle is the Carnot cycle. Note that the reversible cycles cannot be achieved in practice because of irreversibilities associated with real processes. But, the reversible…

The efficiency of a heat engine cycle greatly depends on how the individual processes are executed. The net work can be maximized by using reversible processes. The best known reversible cycle is the Carnot cycle. Note that the reversible cycles cannot be achieved in practice because of irreversibilities associated with real processes. But, the reversible…

Second law of thermodynamics overcomes the limitations of first law of thermodynamics. First law of thermodynamics does not tell how much of heat is changed into work. Second law of thermodynamics shows that the total heat supplied to a system cannot be transferred solely into the work using single reservoir, i.e., some part of heat…

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 steady flow energy…