Evaluate total heat of steam - thermodynamics, Mechanical Engineering

Evaluate total heat of steam:

10 kg of wet saturated steam at 15 bar pressure is superheated to the temperature of 290°C at constant pressure. Find heat needed and the total heat of steam. The dryness fraction of steam is 0.85.

Sol.: From steam table, we get following data:

Absolute pressure (P)

bar

Saturation

temperature (t) ºC

Specific enthalpy kJ/kg

Water (hf)

Latent heat (hfg)

15

198.3

844.6

1947

Total heat of 10 kg wet saturated steam

=10 × 2499.55 = 24995.5 kJ                                                   .......ANS

Total heat of 1 kg superheated steam can be given by Hsup  = hf  + hfg  + Cp(tsup  - ts) kJ

= 844.6 + 1947 + 2.1 × (290 - 198.3) kJ

= 2984.17 kJ                                                                               .......ANS

Total heat of 10 kg superheated steam =10 × 2984.17 = 29841.7 kJ         .......ANS

= hf + hfg + Cp(tsup - ts) - (hf + xhfg)

= hfg  + Cp(tsup  - ts) - xhfg

=1947 + 2.1 x (290 - 198.3) - 0.85 x 1947 kJ = 484.62 kJ

Heat which is required to convert 10 kg wet saturated steam into 10 kg superheated steam

=10 × 484.62 = 4846.2 kJ                                                        .......ANS

Total heat of 1 kg wet saturated steam can be given by Hwet  = hf  + xhfg  kJ

= 844.6 + 0.85 × 1947 kJ = 2499.55 kJ

Heat which is required to convert 1 kg wet saturated steam into 1 kg superheated steam

= Hsup  - Hwet,

here Hsup = enthalpy of 1 kg superheated steam = hf + hfg + Cp(tsup - ts) kJ

Hwet = enthalpy of 1 kg wet saturated steam = hf  + xhfg  kJ

Heat which is required to convert 1 kg wet saturated steam into 1 kg superheated steam

Posted Date: 10/15/2012 7:24:01 AM | Location : United States







Related Discussions:- Evaluate total heat of steam - thermodynamics, Assignment Help, Ask Question on Evaluate total heat of steam - thermodynamics, Get Answer, Expert's Help, Evaluate total heat of steam - thermodynamics Discussions

Write discussion on Evaluate total heat of steam - thermodynamics
Your posts are moderated
Related Questions
Spanners: These are used to tighten and loosen nuts and bolts. These are made according to standard nut and bolt sizes and in vanadium steels. The following types of spanner are u

Determine the elongation of plate: Q: A steel bar AB which is having uniform thickness 2 cm, tapers from 1.5 cm to 7.5 cm uniformly in a length of 50 cm. From 1 st principle

Hello to whom it may concern. I am currently having much trouble with a physics problem. I have an inverted L beam lying on a table. At the end of the flat piece laying on the t


Pole: this is the centre of finite rotation of the coupler. Relative Pole: this is the pole of coupler associated to other moving link. Accuracy Points: The points at w

Maximum Extraordinary Effect Determine the direction of propagation in quartz (ne = 1.553 and no = 1.544) at which the angle between the wave vector k and the Poynting vector S

Determine the maximum torque - shaft: Determine the maximum torque that can be safely transmitted by a shaft of 400 mm diameter, if (a) the maximum allowable shear stress i

a) Illustrate with neat and clean diagram the measurement of brake power by prony brake Dynamiter OR Belt transmission type Dynamiter. b) A torsion dynamometer is fixed to a pro

Process units should have staggered access from at least two directions. The space between battery limits of adjoining units should be kept clear and open. Do not consider the clea