MULTIPLE QUESTION ANSWERS ON HEAT TRANSFER — Sheet 2– Fin increases the rate of heat transfer by increasing the(a) Temperature difference, (b) Surface area, (c) Film coefficient (d)None Ans: (b) The efficiency of a fin of infinite length is (a)Infinity, (b) 100 %, (c) zero, (d) None, (c) In case of […]
MULTIPLE QUESTION ANSWERS ON HEAT TRANSFER — Sheet 1 During conduction of heat, there is a physical motion of the (a) Crystal lattice, (b) Main body, (c) Crystal lattice as well as main body, (d) None Conduction heat transfer takes place (a) In solids only, (b) In liquids only, (c) In gases only, […]
Dimensional Analysis–Part 3 PROCEDURE FOR BUKINGHAM’S π METHOD Let total variables be ( X1, X2, X3, …, Xn ) = n , say n=6 Write X1 = F ( X2, X3, …, Xn) Now write it in the equation form containing n variables as F1 ( X1, X2, X3, …, Xn) = 0 Let m be the total fundamental dimensions for the n variables, say m= 4=M,L,T, θ Then number of dimensionless group in this case will […]
Multiple Choice Questions (mcq) on Heat Transfer—Overall heat transfer coefficient, heat flux and temperature variation Overall heat transfer coefficient is associated with (a) Conduction (b) Convection (c) Radiation (d) None (Ans: d) Overall heat transfer coefficient is associated with (a) Conduction and radiation (b) Convection and radiation (c) Radiation, convection and conduction (d) None (Ans: […]
Multiple Choice Questions (mcq) on Heat Transfer —-Conduction Thermal conductivity of metals with addition of alloying elements (a) Increases (b) Decreases (c) Remains constant (d) None (Ans: b) Thermal conductivity of metals with increase of hardness (a) Increases (b) Decreases (c) Remains constant (d) None (Ans: b) Thermal conductivity of a material with dampness (a) Increases […]
Multiple Choice Questions (mcq) on Heat Transfer —Conduction Poisson’ equation in heat transfer deals with (a) Steady state of heat transfer (b) Unsteady state of heat transfer (c) Steady as well as unsteady states of heat transfer (d) None (Ans: a) Laplace equation in heat transfer deals with (a) Steady state of heat transfer (b) Unsteady […]
Multiple Choice Questions (mcq) on Heat Transfer—-Basic Heat Transfer 2 Critical radius of insulation refers to (a) Minimum rate of heat transfer (b) Maximum rate of heat transfer (c) Constant rate of heat transfer (d) None (Ans: b) Critical radius of insulation for a cylinder is equal to (a) 3k/ho (b) 2k/ho (c) 1k/ho […]
Multiple Choice Questions (mcq) on Heat Transfer —-Basic Heat Transfer 1 Conduction is most prominent in (a) Fluids (b) Solids (c) Gases (a) None (Ans:b) Convection is most prominent in (a) Fluids (b) Solids (c) Gases (d) None (Ans:a) Radiation is most prominent in (a) Fluids (b)Solids (a) Gases (d) None (Ans:d) […]
Short Interview Question Answers on Pool Boiling Correlations and Bubble Parameters in Boiling Heat Transfer Nucleate boiling correlations There are five Pool boiling correlations. (i) General correlation for no phase change q=hA ΔTe Where h is heat transfer coefficient for nucleate boiling (ii) ROSENHOW correlation for Nucleate boiling Q= µlhfg (g(ρl–ρv)/σ)0.5 (CplΔTe/(CslhfgPrln))3 Where n=1 for […]
Short Interview Question Answers on Boiling Regimes in Pool Boiling (POOL BOILING CURVE) Heat Transfer 8. List the various boiling regimes. Various boiling regimes as shown in the figure. Figure: Pool boiling curve (FARBER) 1. Free Convection: Region 1: In This, there is no bubble formation. There is only rise of […]