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# Test: Turbulent Film Condensation

## 10 Questions MCQ Test Heat Transfer | Test: Turbulent Film Condensation

Description
This mock test of Test: Turbulent Film Condensation for Chemical Engineering helps you for every Chemical Engineering entrance exam. This contains 10 Multiple Choice Questions for Chemical Engineering Test: Turbulent Film Condensation (mcq) to study with solutions a complete question bank. The solved questions answers in this Test: Turbulent Film Condensation quiz give you a good mix of easy questions and tough questions. Chemical Engineering students definitely take this Test: Turbulent Film Condensation exercise for a better result in the exam. You can find other Test: Turbulent Film Condensation extra questions, long questions & short questions for Chemical Engineering on EduRev as well by searching above.
QUESTION: 1

### Which parameter is responsible for commencement of the turbulent flow?

Solution:

The character of condensate film can range from laminar to highly turbulent.

QUESTION: 2

### The transition from laminar to turbulent flow occurs at a critical Reynolds number of

Solution:

For turbulent film condensation on vertical surfaces, Kirk bride has suggested the correlation for the average heat transfer coefficient which is valid for Reynolds number greater than 1800.

QUESTION: 3

### A condenser is to be designed to condense 225.0 kg of steam per hour at a pressure of 0.15 bar. A square array of 400 tubes, each of 6 mm in diameter, is available for the task. If the tube surface temperature is to be maintained at 26 degree Celsius, make calculations for the length of the tube

Solution:

sat = 54 degree Celsius and h f g = 2373000 J/kg, t f = 40 degree Celsius and h v = 0.725 [k 3 g p 2 h f g/l δ (t sat – t s)] 0.25 = 5202.34 W/mK. Total S.A of 400 tubes = 7.536l and heat flow rate = m h f g.

QUESTION: 4

The outer surface of a vertical tube is 1.25 m long and outer diameter is 50 mm is exposed to saturated steam at atmospheric pressure. If the tube surface is maintained at 80 degree Celsius by the flow of cooling water through it, determine the rate of heat transfer to the coolant

Solution:

v = 0.943 [k 3 p 2 g h f g/δ l (t sat – t s)] 0.25 = 5046.8 W/m 2 k and heat flow rate = 19879 W.

QUESTION: 5

Consider the above problem, find the rate at which steam is condensed at the tube surface

Solution:

Steam condensation rate = 198789/2285 * 10 3 = 8.7 * 10 -3.

QUESTION: 6

What is the value of characteristics length in turbulent film condensation?

Where, δ is length of the plate

Solution:

d = 4 A/P = 4 b δ/b = 4 δ.

QUESTION: 7

What is the value of Reynolds number in terms of mass flow rate?

Where, δ is length of the plate and b id width of the plate

Solution:

R = V 4 δ p/δ = 4 m/δ b.

QUESTION: 8

Kirk bride criterion is given by

Solution:

This is valid for Re greater than 1800.

QUESTION: 9

The relation between relative effectiveness of horizontal and vertical tubes as condensing surfaces is given by

Solution:

h/h = 0.725/0.943 [(l/d) 0.25].

QUESTION: 10

For n-tubes in a vertical column of the tube bank pattern, identify the correct statement

Where, D is the diameter of a single tube in the bank

Solution:

It should be n times the diameter of a single tube in the bank.