Reynolds Experiment
It was in 1883 when Osborne Reynolds, a famous scientist and engineer tried to experiment on the relationship between the stability of fluid motion and the transition to turbulence. His final apparatus consisted of a glass-sided tank, 6 feet long, 18 inches deep and 18 inches wide. Inside it was a glass tube with `a trumpet mouth of varnished wood, great care being taken to make the surface of the wood continuous with that of the glass'. On the right-hand side, the tube was connected to an iron pipe equipped with a valve which could be controlled by means of a long lever. On the left-hand side is the device for introducing a streak of dye into the trumpet, while a float and dial indicated the water-level in the tank and hence the volume being discharged through the glass tube. The experiment, made in 1880, consisted of filling the tank with water, allowing several hours for conditions to become steady, then opening the valve, at first only slightly (http://www.eng.man.ac.uk).
Fig. 2.1. The ReynoldsÂ’ ApparatusThe average flow velocity V could be defined if the volume flow rate Q was measured by capturing the flow in a bucket, and divided by the cross-sectional area of the pipe, A. In the first fluid flow rate in the downstream direction, the dye filament stayed straight and steady. This indicated that a smooth, well-behaved flow was maintained near the centerline and that Q was low enough. As the flow rate was increased, the dye filament became increasingly unsteady. This led to the filament break up and a cloud of dye was created.
With this experiment, the relationship between four different parameters was achieved. This is known as the ReynoldsÂ’ number. NRe is a dimensionless variable which classifies the flow of incompressible and compressible fluids in...
More Chemical Engineering
essays:
Fire Protection
... an effective fire shield. The increase of temperature through the cross sectional area of concrete is relatively slow due to its aggregates ... low pressure). - Overpressure phase during which the fire retardant is forced into the wood. - End vacuum reducing the egress of the ...
Sedimentation
... Principles section). It is at this point where the clear liquid interface approaches the solid-liquid interface. As they approach, zone B increases in fluid viscosity and density. This causes a sharp decrease in settling velocity for ...
Fire Safe Design Commercial Building Construction
... of the fire deceleration to the saturate chamber (in small force). * value="3" Overpressure stage throughout which the fire deceleration is ... vermiculite materials. They must be applied fully around the steel sections to work effectively, and joints between boards must be covered ...
Catalyst - Preparation and Characterization
... include selectivity, activity, crush strength, abrasion resistance and resistance to fluid flow . As a result the design of a catalyst involves both ...
Cyclone
... lighter flow stream rises. As the fluid or vapor reaches the top of the vortex, it is passing by the difference in pressure through a tube that ...
Adsorption
... attractive forces between molecules of the fluid itself (Foust et. al., 1980). Chemical adsorption, on the other hand, involves chemical interaction between the adsorbed fluid and ...
Pipe corrosion
... not react with the fluid flowing through the pipe is preferable. With the development of plastic piping, this is now ... labor cost of installation. There are many misconceptions about plastic piping (i.e. they cannot be use in potable water systems) but the cheaper cost will ultimately shift use from ...
Forensic Science
... cross- contamination. It is also wise to take comparative samples, so that evidence can be compared to normal or controlled pieces. Unbreakable bottles with lids are good for such things as hair, glass ...