UNIVERSITY OF WAH
WAH ENGINEERING COLLEGE
(Mechanical Engineering Department)
Quiz – 3
Course Title: Measurement and Instrumentation Course Code: ME-214
Semester & Section: 4th (A & B) Faculty: Mr. Haider Ali
Maximum Marks: 10 Deadline: 15-May-2020
Student Name: _Abdul Aziz Reg. #__UW-18-ME-BSC-012_______________
PLO-1: Engineering Knowledge: An ability to apply knowledge of mathematics, science, engineering fundamentals and an
engineering specialization to the solution of complex engineering problems.
PLO-2: Problem Analysis: An ability to identify, formulate, research literature, and analyze complex engineering problems reaching
substantiated conclusions using first principles of mathematics, natural sciences and engineering sciences.
CLO-1: Explain the basic concepts of Measurement & Instrumentation, fundamentals of Measurement systems and Uncertainty and
working of different transducers used to measure temperature, pressure, flow rate, velocity, position, torque and forces applied
CLO-2: To identify and select a suitable transducer for measuring temperature, pressure, flow rate, velocity, position, torque and
forces applied for a given problem statement.
Course Learning Outcome Program Learning Outcome Learning Domain
CLO-1 PLO-1 Cognitive 2
CLO-2 PLO-2 Cognitive 4
Problem Statement
Question # 1 (CLO – 2, PLO – 2)
Mr. Muhammad Ishaq has built a 3story lavish house in DHA phase 2 Rawalpindi. He has built a water tank at
the top of 2nd floor. The water tank has capacity of 500 liters. However, he is very worried about the loss of
water whenever there is an overflow. You are requested to solve this problem of respectable person and suggest
him a level measurement instrument with a control unit to ON and OFF the water pump when the level in
minimum and maximum respectively.
1. Select a level measurement transducer considering its advantages and limitations. (You are required to
write the key advantages and limitations in support of your selection)
2. Make a schematic diagram detailing all the components i.e., pump, water tank, maximum and minimum
of water level in water tank, level measuring transducer, controller.
Answer
Differential pressure Transducer will be used for this purpose. In this type of flowmeter onstruction is placed in
pipe and fluid pressure difference is being measured. This differential pressure is characterized in order to
achieve flow measurement. It is very easy and quick to develop differential pressure flowmeter. In basic
implementation, disk or orifice is placed in the pipe. Opening of this orifice is kept smaller compare to inner
diameter of the pipe. This is shown in the figure-1. Upstream and downstream pressure measurement of the
orifice provide differential pressure across the pipe.
Benefits or advantages of Differential Pressure Flowmeter
Following are the benefits or advantages of Differential Pressure Flowmeter:
➨It is useful for gases, liquids and steam.
➨It is also available for viscosity measurement.
➨It can be used for extreme pressure and temperatue conditions.
➨Measurement range can be modified as per need.
➨There are no moving parts.
➨It can be configured in order to measure bidirectional flow.
➨It is used over wide range of sizes.
Drawbacks or disadvantages of Differential Pressure Flowmeter
Following are the drawbacks or disadvantages of Differential Pressure Flowmeter:
➨It supports small span. This is due to square root relation between flow rate and differential pressure.
➨The results are affected due to changes in the pressure and density.
➨It is not most accurate flow measurement technique.
➨Pressure drop is observed in orifice plates.
➨If edge sharpness is assured in orifice plates, then there will be no solids or contamination. Inspite of no
moving parts, orifice plate used in its construction is a wear prone point.
➨It has very long inlet and outlet sections.
➨It is very expensive to install differential pressure lines, sensors and fittings.
➨It has high cost of maintenance.
Schematic Diagarm
