GATE ME 2024 | Convection Question 1 | Heat Transfer

GATE ME 2024

MCQ (Single Correct Answer)

-0.33

Consider incompressible laminar flow over a flat plate with freestream velocity of $u_{\infty}$. The Nusselt number corresponding to this flow velocity is $Nu_1$. If the freestream velocity is doubled, the Nusselt number changes to $Nu_2$. Choose the correct option for $Nu_{2}/Nu_{1}$.

$\sqrt{2}$

$2$

$1.26$

$1$

GATE ME 2024

MCQ (Single Correct Answer)

-0.33

Consider a hydrodynamically fully developed laminar flow through a circular pipe with the flow along the axis (i.e., z direction). In the following statements, $T$ is the temperature of the fluid, $T_w$ is the wall temperature and $T_m$ is the bulk mean temperature of the fluid. Which one of the following statements is TRUE?

For a thermally fully developed flow, $\frac{\partial T}{\partial z} = 0,$ always.

For constant wall temperature of the duct, $\frac{dT_m}{dz} = $ constant.

Nusselt number varies linearly along the z direction for a thermally fully developed flow.

For constant wall temperature $(T_w > T_m)$ of the duct, $\frac{dT_m}{dz}$ increases exponentially with distance along z direction.

GATE ME 2023

MCQ (Single Correct Answer)

-0.33

Consider incompressible laminar flow of a constant property Newtonian fluid in an isothermal circular tube. The flow is steady with fully-developed temperature and velocity profiles. The Nusselt number for this flow depends on

neither the Reynolds number nor the Prandtl number

both the Reynolds and Prandtl numbers

the Reynolds number but not the Prandtl number

the Prandtl number but not the Reynolds number

GATE ME 2022 Set 2

MCQ (Single Correct Answer)

-0.33

Which of the following non-dimensional terms is an estimate of Nusselt number?

Ratio of internal thermal resistance of a solid to the boundary layer thermal resistance

Ratio of the rate at which internal energy is advected to the rate of conduction heat transfer

Non-dimensional temperature gradient

Non-dimensional velocity gradient multiplied by Prandtl number