Heat Transfer Multiple Choice Questions & Answers (MCQs) on “Model Studies And Similitude”.
1. Which is a full size structure employed in the actual engineering design?
a) Proton
b) Prototype
c) Electron
d) Neutron
Answer: b
Clarification: The prototype operates under the actual working conditions.
2. Which term refers to the theory and art of predicting prototype conditions from model observations?
a) Nusselt number
b) Dimensional homogeneity
c) Thermal boundary layer
d) Similitude
Answer: d
Clarification: It prescribes the relationship between a full scale flow and a flow involving smaller but geometrically similar boundaries.
3. The results obtained from experiments on models can be applied to prototype only if a complete similarity exists between the model and prototype and for that the two systems may be
(i) Geometrically similar
(ii) Kinematically similar
(iii) Dynamically similar
Identify the correct statements
a) i and ii
b) ii and iii
c) i, ii and iii
d) i and iii
Answer: c
Clarification: It should be geometrically, cinematically and dynamically similar.
4. Geometrically similarity prescribes that the ratio of the corresponding linear dimensions of the two systems are
a) Unity
b) Same
c) Never same
d) May be twice
Answer: b
Clarification: It refers to the similarity of shape and form.
5. Thermal similarity refers to the comparison of two systems made on the basis of their
a) Temperature
b) Specific heat
c) Heat flux
d) Length
Answer: d
Clarification: A similarity in thermal quantities is achieved when Prandtl number is same for both the fields.
6. The comparison of two systems made on the basis of their temperature, specific heat and heat flu is known as
a) Dynamic similarity
b) Kinematic similarity
c) Thermal similarity
d) Geometrical similarity
Answer: c
Clarification: It is known as thermal similarity.
7. The similarity of masses and forces of the corresponding particles of flow is known as
a) Kinematic similarity
b) Dynamic similarity
c) Geometrical similarity
d) Thermal similarity
Answer: b
Clarification: Systems are dynamically similar if the corresponding particles experience the similar force.
8. The similarity of motion is known as
a) Thermal similarity
b) Dynamic similarity
c) Geometrical similarity
d) Kinematic similarity
Answer: d
Clarification: Both the systems undergo similar rates of change of motion.
9. The similarity of shape and form is known as
a) Geometrical similarity
b) Thermal similarity
c) Geometrical similarity
d) Kinematic similarity
Answer: a
Clarification: They may differ in size but are identical in shape.
10. A similarity in thermal quantities is achieved when
a) Nusselt number is same for both the fields
b) Nusselt number is different for both the fields
c) Prandtl number is same for both the fields
d) Prandtl number is different for both the fields
Answer: c
Clarification: A similarity in thermal quantities is achieved when Prandtl number is same for both the fields.