HOW DOES A JET ENGINE WORK?

Jet engines create forward thrust by taking in a large amount of air and discharging it as a high-speed jet of gas. The way they’re designed allows aircraft to fly faster and further compared to propeller-driven aircraft. Their development and refinement over the course of the last 65 years has made commercial air travel more practical and profitable, opening the world to business and recreational travelers.

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HYDRAULIC JACK or HYDRAULIC PRESS

HYDRAULIC JACK or HYDRAULIC PRESS
The hydraulic jack is a device used for lifting heavy loads by the application of much smaller force. It is based on Pascal’s law, which states that intensity of pressure is transmitted equally in all directions through a mass of fluid at rest.


WORKING PRINCIPLE: The working principle of a hydraulic jack may be explained with the help of Fig. 23. Consider a ram and plunger, operating in two cylinders of different diameters, which are interconnected at the bottom, through a chamber, which is filled with some liquid.

                                                 Fig. Hydraulic jack Fig. Plunger


Let
W= Weight to be lifted,
F = Force applied on the plunger,
A = Area of ram, and
a = Area of plunger.
Pressure intensity produced by the force F, p = F/Area of plunger = F/a
As per Pascal’s law, the above intensity p will be equally transmitted in all directions.
Therefore, The pressure intensity on ram = p = F/a = W/A or W= F(A/a)
Above Equation indicates that by applying a small force F on the plunger, a large force W may be developed by the ram.
Mechanical advantage of press = A/a
If the force in the plunger is applied by a lever which has a mechanical advantage (L/l) then total mechanical advantage of machine = (L/l)(A/a)

The ratio (L/l) is known as leverage of press.
Hydraulic jack may be employed for the following jobs:

• Metal press work (to press sheet metal to any required shape).
• Drawing and pushing rods.
• Bending and straightening any metal piece .
• Packing press

The Basic Concept, Construction, and Working Principle of Hydraulic Pumps

Basic Concept of a Pump

A pump in general is a machine which imparts energy to anything flowing through it. This can be any fluid, heat or even electrons. The devices pumping heat are called as heat pumps and electrical batteries can pump electrons. The spontaneous tendency of anything is to flow from high potential to low potential and this natural tendency is harnessed in many applications. But the pump does exactly the reverse; it forces something to move from low potential to high potential. For this purpose pumps use energy and by their functioning transfer that energy to the substance flowing through them.
Fluid pumps or Hydraulic pumps move fluids and displace them from one position to another and in course energizes them. In fluids this energy is manifested as its pressure and velocity. Similarly, heat pumps move heat from low temperature to high temperature against its natural tendency to flow from high temperature to low temperature. An electrical battery is also a type of pump; it pumps electrons in a circuit from low electrical potential to high electrical potential which is against the spontaneous tendency of electrons to move from high electrical potential to low electrical potential. Hence, an electrical battery can be called as an Electron Pump.

Hydraulic Pump Construction

Basically a fluid pump or hydraulic pump is a device or machine having moving mechanical components which uses energy from some source, generally electrical, supplied to it in form of mechanical energy by electrical motor.
Generally pumps have rotating parts run by the electrical motors. The rotating parts of pumps can be some volume defining components which can form an enclosed envelope of volume where the fluid can captured and displaced. Other type of rotating parts can be blades mounted on discs or shafts which rotate with the driving power and transfers that to the fluid by making it move with increased velocity.

Basic Working Principle

In simple words we consider a pump to be a black box to understand its working. Fluid enters a pump at certain velocity and pressure, which may be even zero, and leaves it with increased energy, that is, velocity and pressure. For this a pump consumes a certain amount of energy from any external source. Now, what is happening inside that black box? There are rotating components inside which move the fluid either by confining it in definite volumes and then displacing it or by imparting energy to the fluid by dynamic action of the moving parts and increasing velocity and pressure of the fluid.

Fluid Pumps

Fluid Pump or Hydraulic Pump is a machine which transfers the energy from its moving parts to the fluid passing through the machine. The energy transferred from the Pump to the fluid appears as the pressure and velocity of the fluid. Know more about Fluid or Hydraulic Pumps in this article series.