About Ejectors General Information
EJECTORS (INJECTORS) OR JET PUMPS belong to the group of jet machines.
Compared with other pumps they have a series of advantages:
- simple construction,
- small mass and dimension,
- easy to handle and maintain,
- no mobile parts,
- do not require lubrication,
- easily mounted in all positions,
- do not require special bases,
- stable, quiet and noiseless operation,
- allow regime change in wide ranges,
- cheep,
- long lifetime.
One of their characteristics is that they do not require driving engines as they use the energy of input fluids for driving.
Based on the theory we developed, many experiments and great experience on many different types of installations optimization of current and geometric parameters was performed enabling operation with a high degree of utilization.
n = 0.25 – 0.75
Ejectors are widely applied in many fields. In the last few years several patents have been registered in the world and this country (our patents) that give new original solutions simplifying existing technological procedures.
Ejectors are suitable for automation with minimal occasional work control.
Ejectors consist of:
- jets with a driving fluid attachment,
- mixing chamber with an attachment for fluid intake,
- diffuser with an emptying attachment.
Principle of ejector operation: All types of ejectors, regardless of their purpose and size, operate on the same principle. For operation they use energy of the input fluid. Fluid with a higher input pressure is called a driving fluid, while fluid with a lower input pressure is pumped in. Several different fluids can be pumped in at the same time.
All fluids can be used as driving or pumped: liquids (emulsions, suspensions), gasses, vapor and all other materials that can become liquid. All combinations are possible.
Ejector construction was performed so that the fluid pumped in is taken in, compressed and then driven with the energy of the driving fluid.
Main ejector operations are:
- drive,
- pumping in and mixing,
- emptying.
Dr Ljubomir Petrovic, founder of this company defended his PhD thesis titled: “Theoretical determination of optimal current and geometric ejector parameters” at the Faculty of Mechanical Engineering in Belgrade in 1981.
At the entrance to the mixing chamber particles of the driving fluid meet particles of the pumped fluid. They collide with each other, mix with them and take them along. Neighboring particles of the inlet port move into the space left by the removed pumped fluid thus forming a stream in the direction of the diffuser. On their path through the chamber particles of the driving fluid surrender part of their energy and slow down and particles of the pumped in fluid accept part of the energy and accelerate. In the ejector chamber due to different stream rates both fluids are broken into the smallest particles and large active interacting surfaces form. The large active surface enables formation of a completely homogeneous mixture with a fast interchange of energy (mechanical, heat and chemical).