Downloaded 34 times
More Related Content
Vacuum pumps
- 1.
- 2. History Before thevacuum pump, the suction pump was invented. In the city of Pompeii, dual-action suction pumps were found. In the 13th century, an Arabic engineer also explained suction pumps. The suction pump later came up again in Europe from the 15th century. By the 17th century, water pump designs had improved and they produced measurable vacuums, but this was not understood immediately. It was understood by the people that suction pumps could not pull water beyond a certain height.
- 3. The limitappeared as an hinderance to irrigation projects, mine drainage, and decorative water fountains. It was Otto von Guericke during the year 1654 who invented the first vacuum pump and conducted Magdeburg hemispheres experiment, showing that teams of horses could not separate two hemispheres from which the air had been evacuated. Similarly, Robert Boyle improvised on Guericke’s design and conducted experiments on the properties of vacuum.
- 4. What is aVacuum Pump? A vacuum pump is a tool that eliminates gas molecules from a sealed volume so as to leave behind a partial vacuum. It removes gas from an area, leaving a partial vacuum behind. It also will remove water from one area to another, exactly like sump pump does In a basement. They are utilised in an industrial setting in order to produce vacuum tubes and electric lamps, and to process semiconductors. The pumping speed is a very important factor in measuring its performance. Pumping speed means the volume flow rate of a pump at its inlet.
- 5. Pumping ratevaries for each type of pump and the type of gases being pumped. The average volume flow rate of the pump changes depending on the chemical composition of the gases remaining in the chamber. The performance level is also measured by throughput. This means pumping speed multiplied by the gas pressure in the inlet. Throughput is known as the number of molecules pumped out of per unit time at a constant temperature.
- 6. Structure of thevacuum pump
- 7. Types There are varioustypes of vacuum pumps and each vary from the other in various aspects. They are as follows : Positive Displacement Pump Momentum Transfer Pump Regenerative Pump Entrapment Pump Other Types
- 8. Positive Displacement Pump It has an increasing cavity on the suction side and a reducing cavity on the discharge side. Liquid flows into the pumps as the cavity on the suction side increases and the liquid flows out of the discharge as the cavity collapses. The volume is stable given each cycle of operation.
- 9. Momentum Transfer Pump The Momentum Transfer vacuum pump is where gas molecules are accelerated from the vacuum side to the exhaust side is known as momentum transfer pump. On the basis of laws of fluid dynamics, matter flows differently at different pressures. In the atmospheric pressure and mild volumes, the molecules interact with each other and push on their neighbouring molecules. This process is known as viscous flow. The molecules interact with the walls of the chamber frequently rather than other molecules when the distance between the molecules increases. This stages is generally called high vacuum and is way more effective than positive displacement.
- 10. Entrapment Pump Itworks using chemical reactions, are known to perform better and more effectively because they are usually placed inside the space or container to be vacuumed. The molecules in the air create a thin film which is removed by the entrapment pumps as they chemically react to the internal surfaces of the pump.
- 11. Regenerative Pump Itis also called a turbine or peripheral pump. The impeller has vanes on either sides of the rim that rotate in a ring like channel in the pump’s casing. The fluid does not discharge freely from the tip of the impeller but is recirculated back to a lower point on the impeller diameter. This recirculation, or regeneration, increases the head developed.