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PY 3: GATE ME 2019 Official Paper: Shift 1

Option 1 : Nu_{q }> Nu_{T}

ST 1: General Awareness

7043

15 Questions
15 Marks
15 Mins

__Concept: __

Always remember standard results mentioned below;

Part – I For constant surface heat flux (q_{s} = constant);

Hydrodynamically and thermally fully developed laminar flow through a circular pipe of constant cross section

Nu_{q} = 4.36 …1)

Part – II For constant wall temperature (T_{w} = constant)

For this case

Nu_{T} = 3.66 …2)

__Calculation: __

Comparing 1) and 2)

Nu_{q} > Nu_{T} ⇒ Option A is correct.

__Key Points__

Go through both derivations (i.e. q_{s} = constant and T = constant) and remember graphs of both cases.