Brake System Classification

Brake system used to slow down a vehicle by converting its kinetic energy into heat energy.

Classification of Brake system :

On the basis of mode of actuation

• Foot brake (also called main brake) operated by foot pedal

• Hand brake – it is also called parking brake operated by hand

On the basis of mode of operation

• Air brakes

• Electric brakes

• Hydraulic brakes

• Mechanical brakes

• Vacuum brakes

On the Basis of Action on Front or Rear Wheels

• Front-wheel brakes

• Rear-wheel brakes

On the Basis of Method of Application of Braking Contact

• Externally – contracting brakes
• Internally – expanding brakes

Types of fluid flow in pipes - laminar, turbulent, transient

Pipes are in circular cross section area, identical to the shape of a roll of paper towels. We general use pipes in our homes to supply water from water tank to kitchen, bathroom.

Fluid flow can be classified into three types:

• Laminar flow

• Turbulent flow

• Transitional flow

Laminar flow :

Occurs when the fluid flows in parallel layers, with no mixing between the layers. Where the center part of the pipe flow the fastest and the cylinder touching the pipe isn't moving at all.

The flow is laminar when Reynolds number is less than 2300.

Turbulent flow :

In turbulent flow occurs when the liquid is moving fast with mixing between layers. The speed of the fluid at a point is continuously undergoing changes in both magnitude and direction.

The flow is turbulent when Reynolds number greater than 4000.

Transitional flow :

Transitional flow is a mixture of laminar and turbulent flow, with turbulence flow in the center of the pipe and laminar flow near the edges of the pipe. Each of these flows behave in different manners in terms of their frictional energy loss while flowing and have different equations that predict their behavior.

The flow is transitional when Reynolds number is in between 2300 and 4000.

Centrifugal pump efficiency - Mechanical, Hydraulic, Volumetric, Overall efficiencies

Performance of a centrifugal pump can be determined by finding the following efficiencies:

• Mechanical efficiency
• Hydraulic efficiency
• Volumetric efficiency
• Overall efficiency

Mechanical efficiency of a centrifugal pump (ηm):

Mechanical efficiency of a centrifugal pump (ηm) is the ratio of theoretical power that must be supplied to operate the pump to the actual power delivered to the pump.

Mechanical efficiency can be used to determine the power loss in bearings and other moving parts of a centrifugal pump. It determines the actual power that must be supplied to a centrifugal pump for desired result.

Hydraulic efficiency of a centrifugal pump (ηH):

Hydraulic efficiency of a centrifugal pump (ηH) is defined as the ratio of the useful hydrodynamic energy in fluid to Mechanical energy supplied to rotor.

Volumetric efficiency of a centrifugal pump (ηv):

Volumetric efficiency of a centrifugal pump (ηv) is defined as the ratio of the actual flow rate delivered by the pump to the theoretical discharge flow rate (flow rate without any leakage) that must be produced by the pump.
Volumetric efficiency can be used to determine the amount of loss of liquid due to leakage in a pump during the flow.

Overall efficiency of a centrifugal pump (ηo):

Overall efficiency of a centrifugal pump is the ratio of the actual power output of a pump to the actual power input to the pump. It is the efficiency that determines the overall energy loss in a centrifugal pump.

Overall efficiency of a centrifugal pump is the product of the volumetric efficiency and mechanical efficiency of a centrifugal pump.
Overall efficiency of a centrifugal pump (ηo) = Mechanical efficiency (ηm) × Volumetric efficiency (ηv)