Evaluation of heat required - thermodynamics, Mechanical Engineering

Evaluation of heat Required:

Heat which is required to generate steam is different from 'total heat' or enthalpy of steam. Heat required for generating steam means heat needed to produce steam from water the initial temperature of which is tºC (say) which is always more than 0ºC. Total heat or enthalpy of steam means heat needed to generate steam from water the initial temperature of which is 0°C. If initial temperature of water is 0°C, then of course heat needed to generate steam becomes equal to total heat or the enthalpy of steam.

970_Evaluation of heat Required.png

heat required to generate steam can be given by QDry=hf + hfg  - h' kJ/kg,

where h' = heat required to raise 1 kilogram water from 0°C to given initial temperature (say t°C) of water

= mst =1 × 4.2 × (t - 0) = 4.2t kJ [sp. heat of water = 4.2 kJ/kg K].

(b)  When steam is wet saturated, heat needed to generate steam can be given by

Qwet  = hf  + x.hfg - h' kJ/kg.

(c)  When steam is superheated, heat required can be given by

Qsup  =hf  + hfg + CP(tsup  - ts) - h' kJ/kg.

Posted Date: 10/15/2012 6:20:25 AM | Location : United States







Related Discussions:- Evaluation of heat required - thermodynamics, Assignment Help, Ask Question on Evaluation of heat required - thermodynamics, Get Answer, Expert's Help, Evaluation of heat required - thermodynamics Discussions

Write discussion on Evaluation of heat required - thermodynamics
Your posts are moderated
Related Questions
Plastic material and rigid plastic material: For the plastic material, there is stress at which plastic deformation begins. A rigid plastic material is one in which the ela

Clausius inequality - thermodynamics: Whenever closed system undergoes cyclic process, cyclic integral is less than zero (that is negative) for an irreversible cyclic process

Process for solve screw conveyer problem For fully automatic extension of screw conveyer according to screed width we have to go for some design changes, At the end of main

Method of section: Define the method of section? How can you solve the problems with the help of method of section? Sol.: This method is powerful method for determining

Material S48C thickness 4mm pierce hole daimeter 4 mm can do or not? please advise

steady state amplitude

Steps for F-test The Steps followed in the F-Test are as follows: (A) State the hypothesis: Ho: Relationship between Y and all Xs is not significant. HA: Relationship bet

WHAT IS DAMP VIBRATION FACE ANGLE SIMPLE HARMONIC MOTION NATURAL CIRCULAR FREQUENCY FORCE VIBRATION

Steam power plant: Steam power plant converts heat energy Q from combustion of fuel into mechanical work W of shaft rotation which is used to generate electricity. This ty

Find the minimum weight to keep equilibrium: A belt supports the two weights W 1 an d W 2 over a pulley as shown in the figure given below. If W 1 = 1000N, fi