Pulsation bottles

Each cylinder should have suction and discharge pulsation bottles to dampen the acoustical vibrations caused by the reciprocating flow,... 

For smaller, high-speed compressors the piping sizing rules of thumb discussed above, in conjunction with pulsation bottles sized from Figure 11 -24, should be sufficient for individual field compressors. These niles of thumb can also be used for preliminary sizing of piping and bottles in preparation for an analog study. 

Figure 11-24. Pulsation bottle sizing chart lapproximotion). (Reprinted with permission from GPSA Engineering Data Book, 10th Ed.j...

The pulsation control elements can have several forms, such as plain volume bottles, volume bottles with baffles, bottles and orifices, and proprietary acoustical filters. See Figure 3-26 for an example of a compressor with a set of attached volume bottles. Regardless of which device or element is selected, a pressure loss evaluation must be made before the selection is finalized because each of these devices causes a pressure drop. 

Screw compressors of the dry type generate high frequency pulsations that move into the system piping and can cause acoustic vibration problems. These would be similar to the type of problems experienced in reciprocating compressor applications, except that the frequency is higher. While volume bottles will work with the reciprocator, the dry type screw compressor would require a manufacturer-supplied proprietary silencer that should take care of the problem rather nicely. 

In many instances, the design of suction and discharge pulsation dampening drums (or bottles) for reciprocating compressors is based on piston displacement and volumetric efficiency, and this design normally will suffice to reduce peak pulsation to approximately 5% of the line pressure. In special or other cases, experience has shown that operational difficulties (vibrations, meter pulsations, etc.) may indicate that the peak pulse pressure of 5% line pressure is inadequate. Thus, the pressure in pulsation-reduction design selection is... 

The pulsations can cause the use of excess horsepower when compared to the ideal or a system design that reduces pulsations and thereby improves cylinder performance and efficiency. The pulsation shaking forces in the suction and discharge dampeners (bottles) can be evaluated by computer analysis, and the magnitude and frequency in hertz can be reduced to an acceptable level by adjusting the dimensions (size) of the dampeners. The magnitude of the internal forces directly affects the mechanical stress on the nozzles of the cylinder and of the dampeners. Compressor... 

When using this method, it is necessary to assume an allowable pressure drop though the pulsation drum. This pressure drop does not need to be large (V4 -1 lb). However, the higher the allowable pressure drop, the smaller the resulting bottle, because the diameter and the length of the drum vary as (pressure drop) or the volume of the drum varies as (pressure drop) . ... 

Experience has proven that pulsation drums/bottles/ dampeners must be designed and fabricated using exceptionally heavy construction and good welding techniques and that the addition of support gusset plates to reinforce nozzles and other attachments is essential. 

Variable amounts of PETN in 0.1 g increments are charge into inner tubes. The tube is plugged with a 15 mL sample bottle containing inert material. A No. 0 or No. 6 electric cap is fixed on the bottle and detonated under water. The first pulsation period is measured. 

Fig.3.122 shows a test sample attached to the frame. Leg wires are connected to leading wires, and the connection is sealed to be water-tight. The sample bottle is sunk to a depth of 1 m and is detonated. The first pulsating bubble is recorded. 

Relief Valves/Pulsation Dampeners (Volume Bottles)/Inter-Connecting Piping/InitiaT ... 

Fig. 6 Various types of animal cell bioreactors (A) roller bottle (B) rotating disk (C) stirred tank with a marine impeller (D) tank with a pulsating agitator (E) stirred tank with a spin filter (F) airlift (G) fluidized bed and (H) hollow fiber. (View this art in color at WWW. dekker. com.)...

Any accumulation of air bubbles in the bottle due to accidental introduction of air or to the use of undegassed solvents may lead to an enhancement in flow pulsation and a deterioration in flow stability. It is therefore a wise policy to often check the upper part of the displacement bottle for air bubbles, and release them before a degradation of performance occurs. For trouble-free operation, it is also good practice to degas beforehand the solvent and water used for the displacement. 

T) Pressure bottle Pulsation chamber (D Vibration system... 

Pulsation can be controlled using a volume bottle or a pulsation dampener (snubber). A volume bottle is an empty vessel served as a surge drum. Figure 13 can be used to estimate the required volume of a volume bottle. 

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