wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

A plate of thickness 50 mm is heated upto 225C in a furnace and then left in open atmosphere at 25C with convective coefficient of 500 W/m2K. Take thermophysical properties of plate as k=60 W/mK
Using shown graph (Heisler chart) the temperature at centerline of wall after 3 minutes from exposure is equal to
P=7800 kg/m3
c=450 J/kgK
α=1.5×105 m2/s

A
106.3C
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
118.6C
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
C
187.4C
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
199.3C
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is B 118.6C

Bi=(hSk)

s=t2 [characteristic length for plate]

Bi=500×0.02560=0.2083

Bi>0.1 Lumped analysis is not valid

1Bi=4.8

F0=ατs2=1.5×105×180(0.025)2=4.32

From interpolation:
R=0.5+0.50.445(4.324)

R=0.468

R = centerline temperature ratio

TcTTiT=R

Tc2522525=0.468

Tc=118.6C

flag
Suggest Corrections
thumbs-up
0
similar_icon
Similar questions
View More
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Biot, Fourier Number and Heisler Charts
OTHER
Watch in App
Join BYJU'S Learning Program
CrossIcon