What is a rotary lobe pump and how does it work? (Roots-type supercharger simply explained) скачать в хорошем качестве

What is a rotary lobe pump and how does it work? (Roots-type supercharger simply explained)

In this video, we take a closer look at the design and operation of a rotary lobe pump. This is also known as a Roots blower or Roots-type supercharger. The centrepiece of a rotary lobe pump is the pair of counter-rotating lobes. The lobes are also known as rotors or vanes. The fluid to be pumped is pushed between the casing and the rotating vanes. In the case of compressible substances such as gases, compression takes place on the discharge side of the pump. The pump is then referred to as a compressor. The Roots blower is usually driven by an electric motor mounted at the rear. lobe-pumps are used in applications where a continuous flow of air or gas is required. Typical applications include aeration systems in sewage and water treatment plants, where air is pumped into the wastewater to aid biological decomposition. lobe-pumps are also used as compressors for supercharging combustion engines. Rotary lobe pumps are characterised by high reliability, low vibration and noise levels. They also require little maintenance. These Roots blowers or Roots-type superchargers are usually seen on so-called muscle cars, where the compressors are clearly visible on the hood. Roots-type superchargers are usually driven by a belt drive that is connected to the engine. Air is drawn in through a slot at the front and enters the Roots blower housing, which is fitted with cooling fins to cool the air during compression. Inside the Roots blower are the two three-lobed vanes which pump the air between the rotor and the inner wall of the casing from the suction side downwards to the discharge side. The accumulation of air on the discharge side increases the pressure there and the air is compressed accordingly. The undesirable increase in temperature during compression is counteracted by the already mentioned cooling fins on the casing. The compressed and cooled air is then forced into the combustion engine. As a result, more air reaches the engine cylinders, allowing more fuel to be burned and increasing the engine's power output. The pressure ratio between the discharge and suction sides of a Roots blower is usually a maximum of two. Depending on the speed, the efficiency in these cases is approximately 50%. At higher pressure ratios the efficiency drops significantly! In general, the smaller the pressure difference, the more efficient the Roots-type supercharger. 00:00 What is a rotary lobe pump and how does it work? 00:55 Application, advantages and disadvantages of rotary-lobe-pumps 01:37 Construction of the two-lobed rotary vanes (cycloid) 02:37 Three-lobed rotary vane 03:03 Construction of the three-lobed rotary vanes 03:42 Roots-type supercharger