Given,
Pr=1
T∞=500 K
Length=1.5m
Tplate=300 K
U(∞)=10 m/s
v=30×10−6 m2/s
Thermal boundary layer at 0.5 m from is leading edge=δt
Rex=0.5=Uxv=10×0.530×10−6=166,666.67
Since Rex=0.5<5×105. Hence flow is laminar
∴ δ=5x√Rex
=5×0.5√166,666.67
=6.1237×10−3 m
δtδ=11.026(Pr)−1/3
δt=5.97 mm