Why does an air jet spread out?
When such a jet of fluid is injected into quiescent surroundings the original kinetic energy of the jet is gradually dispersed in the turbulent mixing region of the jet. In this way the jet spreads in the form of a cone having a well-defined angle.
What are the advantages of air jet method?
The main advantages of air-jet spinning can be found in two main directions: efficiency and flexibility. The efficiency of the method is attributed to the high production speed of the spinning machines: up to 500 m/min for MVS.
What is a free air jet?
The Free Air Jet Experiment is designed to give insight into the fundamentals of a free jet at various locations inside and outside the core region. The core region is a location in the flow field where the flow has a velocity that is approximately the same as the velocity coming from inside the jet.
What is spinning jet?
Air-jet spinning is a pneumatic method which consists of passing a drafted strand of fibers through one or two fluid nozzles located between the front roller of a drafting system and a take up a device. The drafting system S drafts the input material into a ribbon-like form with parallel fibers.
Why does a jet spread out as it flows downstream?
This is due to a property called entrainment, in which the central high speed jet shares its kinetic energy with parcels of fluid at the margins of the jet, setting them in motion, which then share with other parcels farther off-axis to set them in motion, and so on.
What is dry spinning?
Dry spinning is the fiber formation process that transforms a high vapor pressure polymer solution to a solid fiber by controlled fiber evaporation in the spinline. The key variables in dry spinning are heat transfer, mass transfer and stress on the filament.
What is Airjet yarn?
The air-jet spun yarn, also termed a fasciated yarn, is composed of a central core of essentially parallel fibres bound together by wrappers, and has many distinctive recurring features in wrapping along the yarn length.
What is orifice and free jet flow?
Equipment Description. The orifice and free jet flow apparatus consists of a cylindrical head tank with an orifice plate set into its side (Figure 6.1). An adjustable overflow pipe is adjacent to the head tank to allow changes in the water level. A scale attached to the head tank indicates the water level.
How do you calculate the force of water jet?
If the speed of the water jet is constant (ie. dv/dt=0), the force is given by f = v(dm/dt) where v is the speed of the water exiting the nozzle and dm/dt is the mass flow rate out of the nozzle. The mass flow rate is the volume flow rate x mass/unit volume of water (1 kg/l).
Why rotor spinning is called open end?
Open end spinning works not by a spindle but by the principles of centrifugal force: fibers are fed into a rotating turbine. Thanks to the rotation respectively the velocity, the fibers are pressed against the wall of the rotor until a certain count is reached. A nozzle then pulls the fibers off, creating the yarn.
What is ring spinning process?
Ring spinning is a method of spinning fibres, such as cotton, flax or wool, to make a yarn. In ring spinning, the roving is first attenuated by using drawing rollers, then spun and wound around a rotating spindle which in its turn is contained within an independently rotating ring flyer.
What is jet flow?
A fluid flow in which a stream of one fluid mixes with a surrounding medium, at rest or in motion. Such flows occur in a wide variety of situations, and the geometries, sizes, and flow conditions cover a large range.
How does a jet engine work and how does it work?
All jet engines, which are also called gas turbines , work on the same principle. The engine sucks air in at the front with a fan. A compressor raises the pressure of the air. The compressor is made with many blades attached to a shaft. The blades spin at high speed and compress or squeeze the air.
How are air jets used in HVAC applications?
2.1 Overview In HVAC applications, air jet theory is a well-practised basis for analysing and designing mixing ventilation systems. Air jet theory divides the room into a jet region and an occupied zone. The aim is to predict the extreme values of air velocities and temperatures in the occupied zone.
How is air jet theory used in HVAC?
2 AIR JET THEORY. 2.1 Overview In HVAC applications, air jet theory is a well-practised basis for analysing and designing mixing ventilation systems. Air jet theory divides the room into a jet region and an occupied zone. The aim is to predict the extreme values of air velocities and temperatures in the occupied zone.
How does an air jet weaving machine work?
• The air jet weaving machines are supplied with compressed air from a central compressor in the weave room or are equipped with individual built -in compressors. • The water jet weaving machines are equipped with individual injection pumps to pressurize water supplied from the water main; waste water is discharged into a drain.
All jet engines, which are also called gas turbines , work on the same principle. The engine sucks air in at the front with a fan. A compressor raises the pressure of the air. The compressor is made with many blades attached to a shaft. The blades spin at high speed and compress or squeeze the air.
2.1 Overview In HVAC applications, air jet theory is a well-practised basis for analysing and designing mixing ventilation systems. Air jet theory divides the room into a jet region and an occupied zone. The aim is to predict the extreme values of air velocities and temperatures in the occupied zone.
2 AIR JET THEORY. 2.1 Overview In HVAC applications, air jet theory is a well-practised basis for analysing and designing mixing ventilation systems. Air jet theory divides the room into a jet region and an occupied zone. The aim is to predict the extreme values of air velocities and temperatures in the occupied zone.
• The air jet weaving machines are supplied with compressed air from a central compressor in the weave room or are equipped with individual built -in compressors. • The water jet weaving machines are equipped with individual injection pumps to pressurize water supplied from the water main; waste water is discharged into a drain.