Example of change of enthalpy, Mechanical Engineering

Assignment Help:

Example of change of enthalpy:

Q 0.5kg/s of a fluid flows in steady state process. The properties of fluid at the entrance are measured as p1 = 1.4bar, density = 2.5kg/m3, u1 = 920Kj/kg while at exit properties are p= 5.6 bar, density = 5 kg/m3, u2 = 720Kj/kg. The velocity at entrance is 200m/sec, while at exit it is 180m/sec. It rejects 60kw of heat and rises through 60m during the flow. Find change of enthalpy and rate of work done.     

Sol: Given that:

mf  = 0.5kg/s

P1  = 1.4bar, density = 2.5kg/m3,

u1  = 920Kj/kg

P2  = 5.6 bar, density = 5 kg/m3,

u2  = 720Kj/kg. V1  = 200m/sec

V2  = 180m/sec Q = - 60kw

Z2  - Z1  = 60m h = ?

WS  = ?

Since           h2 - h1  =   U +   P

h2 - h1  = [U2  - U1    + (P2/  2  - P1/   1)]

= [(720 -920) × 103  +   (5.6/5 - 1.4/2.5) × 105]

= [-200 × 103  + 0.56 × 105] = - 144KJ/kg

H =  mf  × (h2 - h1) = 0.5 × (-144) Kj/kg = -72KJ/sec                    .......ANS

By Applying SFEE

84_Isentropic flow through the nozzle3.png

60 × 103  - WS  = 0.5[ - 144 × 103  + (1802  - 1002)/2 + 9.81 × 60]

WS  = 13605.7 W = 136.1KW                    .......ANS


Related Discussions:- Example of change of enthalpy

Press tools, Difference between press forminig and hammer forming

Difference between press forminig and hammer forming

Thin cells, what type of stresses a thin cell is subjected to?

what type of stresses a thin cell is subjected to?

Evaluate the chebyshev spacing for a function, Evaluate the chebyshev Spaci...

Evaluate the chebyshev Spacing for a function y = 2 x 2 - x for the range 0 ≤ x ≤ 2 where four precision point are required. For these precision points, determine φ 2 , φ 3 , φ 4

Compound BArs, three vertical, parallel straight rods, each 2.6m in length ...

three vertical, parallel straight rods, each 2.6m in length have their upper ends firmly secured and their lower supporting a rigid horizontal bar with a weight of 8KN, which cause

What is hybrid sweep, Hybrid Sweep It combines linear and/or non-linear...

Hybrid Sweep It combines linear and/or non-linear sweep via set operations. In this case, two point sets are swept in two different directions and the two resulting swept volum

Power sources-transformer type power sources, Transformer Type Power Source...

Transformer Type Power Sources These are the simplest and cheapest type available for arc welding. These are the mainly used for SMAW, AC SAW and gouging applications. These are

Estimate the weight of the casting, Estimate the Weight of the Casting ...

Estimate the Weight of the Casting A Yoke casting shown in Figure is to be produced by sand casting process. Estimate the weight of the casting if the density of the material

Titanium alloys, Titanium Alloys Pure titanium is a light weight and s...

Titanium Alloys Pure titanium is a light weight and strong ductile metal. This is very strong and as well as highly resistant to corrosion of all kinds but has the drawback su

Service and maintenance procedures, Service and Maintenance Procedures, you...

Service and Maintenance Procedures, you have studied detailed procedure of motorcycle service and maintenance and points to be remembered while servicing. In the next course, you s

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd