Universiti Teknikal Malaysia Melaka Hydraulic and Pneumatic SystemFakulti Kejuruteraan Mekanikal

Tutorial 1 : Introduction to Fluid Power

1) What are the key elements of fluid power?2) What are the features of mobile hydraulics that differentiate it

from stationary hydraulics?3) The Pascal Law states that, if……………………………..4) Name three type of power transmission in the engineering field.

5) The figure above reflects a classification of hydraulic system. Which one is true? Mobile Hydraulics or Stationary Hydraulics.

6) Who is John Brahmah? What is the main contribution of John Brahmah to the world of fluid power?

Standard Full NameBSJICCETOPISOANSI

7) Above is the standard that is currently used in Hydraulic and Pneumatic symbols. Name those standards.

8) There are three important energies in the Bernoulli equation. Name all three and the equation related to each of them.

9) Give 6 advantages of using hydraulics.10) Give 5 disadvantages of using hydraulics.11) What is the difference between laminar flow and turbulent flow?12) What kind of flow that is usually contributing to any leakage in a

hydraulic system?13) What is the definition of Reynolds number in any pipe14) When does laminar flow become turbulent in any pipe? 15) What are two problems if fluid viscosity is too low?

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Universiti Teknikal Malaysia Melaka Hydraulic and Pneumatic SystemFakulti Kejuruteraan Mekanikal

16) Describe the different between fluid transfer system and fluid power system.

17) Describe the difference between the hydraulic and pneumatic applications.

18) Oil is flowing through a 30 mm diameter pipe at 60 lpm. Determine the velocity. (1.41 m/s)

19) A student is measuring the time taken for a hydraulic oil to fill 0.5l of oil in a measuring glass for 45s. What is the mass flow rate of the oil per minute if the specific gravity of the oil is 0.85? (0.561kg/min)

20) A reservoir is filled with hydraulic oil that has a specific gravity 0.8. Calculated the hydrostatic pressure at the bottom of the reservoir if it is filled to a height of 800mm. (6.278kPa)

21) The above sentence discusses about one particular physical properties of fluid. What is it?

22) The Reynolds number for flow through a pipe line is given by

where is the fluid density, Q the average flow through the pipe, the fluid viscosity and D the pipe diameter. Given Q = 40 l/min, D = 3 cm, = .80 g/cm3 and Viscosity = 0.25cm2/s. For the conditions specified, calculate the Reynolds number for this flow rate. (1132)

23) The “bulk modulus” of a liquid is defined by the following equation:

where B is the bulk modulus (always positive), p is pressure change, V is the volume change and V is the volume. If the bulk modulus is 17000 bar and the change in pressure is 200 bar, calculate the percentage of the compressed oil. (1.2%)

24) A dimensionless combination of variables that is important in the study of viscous flow through pipes is called the Reynolds number, Re, defined as VD/ where is the fluid density, V the mean fluid velocity, D the pipe diameter, and the fluid viscosity. A Newtonian fluid having a viscosity of 0.38 Ns/m2 and a specific

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This involves the ability to compress the fluid. The air has high value of this parameter while most liquid has a very low value of this parameter. The physical property also

defines the rigidity of certain fluid.

Universiti Teknikal Malaysia Melaka Hydraulic and Pneumatic SystemFakulti Kejuruteraan Mekanikal

gravity of 0.91 flows through a 25-mm-diameter pipe with a velocity of 2.6m/s. Determine the value of the Reynolds number. (156)

25) What is the meaning of viscosity? Name three type of viscometer shown in the above picture?

26) A hydraulic pump simply creates what? Pressure? Flow? Or Both?27) What is the difference between fixed displacement pump and

variable displacement pump? 28) What is the different between pressure-compensated vane pump

and a balanced vane pump?

29) Name both pumps that are presented in the above figure.

30) If a pump has a displacement volume of 25 cm3. Determine the discharge of the pump in liter per minute if it rotates in 1420 revolution per minutes. (35.5lpm)

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Universiti Teknikal Malaysia Melaka Hydraulic and Pneumatic SystemFakulti Kejuruteraan Mekanikal

31) The typical Rexroth Pump as shown above had been equipped with a component that enables it to control important element in fluid power control. Name the components and the element that it controls.

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