What is Mollier diagram of steam?
Mollier Diagram: It is a graphical representation of steam tables, in which specific entropy is plotted along the ordinate and specific enthalpy along the abscissa. The diagram is divided into two portions by a somewhat horizontal line termed as saturation curve.
What is the entropy of steam?
For steady state conditions, dry saturated steam condenses at constant pressure, and the steam state point moves down the constant pressure line as shown in Figure 2.15. 9. This example considers steam condensing from saturation at 2 bar at 120 °C with an entropy of 7.13 kJ/kg K, and an enthalpy of about 2700 kJ/kg.
What does the Mollier diagram show?
Air is a mixture of mostly oxygen, nitrogen and water vapor. The Mollier diagram is a graphic representation of the relationship between air temperature, moisture content and enthalpy, and is a basic design tool for building engineers and designers.
Which lines have on Mollier diagram?
A typical H-S Mollier diagram for a thermodynamic fluid such as steam is shown in Figure 1. Figure 1. The advantages of such a diagram are that vertical lines represent reversible processes and horizontal lines represent lines of constant energy.
What is use of steam table and Mollier chart?
It is advisable to use Steam-tables or Mollier chart directly for easy and accurate estimation of the properties of steam, such as pressure, temperature, specific volume, enthalpy, entropy etc., which we have calculated by different relations for water/steam in different states under steam generation section.
How do you find the enthalpy of a Mollier chart?
Answer: h = hf + xhfg= 884.6 + 0.85 x 1910.3 = 2508.35 kJ/kg. Locate point ‘1’ at an intersection of 18 bar pressure line and 0.85 dryness fraction line. Read the value of enthalpy (h) and specific volume (v) from Mollier diagram corresponding to point ‘1’.
How do you calculate steam entropy?
For wet steam the change in entropy will be xhfg / Tsat where x is the dryness fraction of steam. The evaporation process on temperature entropy diagram (fig. 3-8) is represented by horizontal line be. There is all water at b and all dry saturated steam at c.
What is Mollier diagram in thermodynamics?
Definition of Mollier diagram : a diagram showing thermodynamic properties of a substance with various quantities (as temperature and pressure) constant especially in terms of entropy and enthalpy as coordinates.
How is an isentropic constant entropy process shown on a Mollier diagram?
A vertical line in the Mollier diagram represents the isentropic process (s = C). A horizontal line in the Mollier diagram represents the isenthalpic process (h = C).
Which properties does the Mollier chart plot?
The Mollier diagram, also called the enthalpy (h) – entropy (s) chart or h-s chart, is a graphical representation of thermodynamic properties of materials. In general, it is a relationship between enthalpy (measure of the energy of a thermodynamic system), air temperature, and moisture content.
What is the use of steam table?
A saturated steam table is an indispensable tool for any engineer working with steam. It’s typically used to determine saturated steam temperature from steam pressure, or the opposite: pressure from saturated steam temperature.
How do you find the entropy of a wet steam?
4.6
- Enthalpy in wet region is calculated by.
- h = hf + xhfg.
- h = hf + x( hg – hg)
- Where h is enthalpy at any point in the wet region, h f is enthalpy at the saturated liquid, hg is enthalpy at saturated vapor and x is the quality of steam.
- Entropy in wet region is calculated by.
- s = sf + xsfg.
- s = sf + x(sg – sf)
What is slope in Mollier diagram?
The short answer: The slope of the mollier diagram (T-s or h-s plot) is directly proportional to the temperature. Hence, as the temperature increases (or as pressure increases), isobars diverge from each other. →dT/ds= T/Cp, increases as temperature increases (Cp is taken constant).
What is the purpose of steam table in thermodynamics?
Steam tables are defined as the thermodynamic data that contain the properties of water or steam. These data are commonly used by engineers. It is normally used to obtain the following properties using steam pressure for saturated steam temperature and saturated temperature for saturated steam pressure.
Does steam have greatest entropy?
The entropy of steam is more than that of water at its boiling point. Explain. At the boiling point, both water and steam (water vapours) exist together and are in equilibrium. However, the entropy of steam is more because of greater randomness of the H2O molecules in the gaseous state than in the liquid state.
How do you calculate enthalpy of steam?
This Enthalpy for Saturated Steam can be obtained at atmospheric pressure from above Table, i.e., hg = 2676 KJ/Kg, So now Enthalpy required for saturated liquid to convert into saturated steam can be obtained as follows, Latent Heat ( he ) = hg – hf = 2676 – 419 = 2257 KJ / Kg.