Hydraulic calculations

The Souders-Brown correlation considers entrainment as the controlling factor. For high liquid loading situations and final design, complete tray hydraulic calculations are required. 

For final design, complete tray hydraulic calculations are required. 

Solution After thorough analysis, including heat and material balances and hydraulic calculations, the initial design flaws were corrected including ... 

Another important consideration in tower design is tray downcomers size. At high ratios of liquid flow to vapor flow a proportionally greater area on the tray must be allotted to the downcomer channel opening. Downcomers are designed from basic hydraulic calculations. If the downcomer is inadequately sized and becomes filled with liquid, liquid level will build on the tray above. This unstable situation will propagate its way up to the tower and result in a flooded tower condition. Excessive entrainment can also lead to this same condition and, in fact, is usually the cause of flooding. 

Section 8.1 provided a description of a core melt. This section backs up to describe thermal-hydraulic calculations of the phenomena before, during, and after the accident, and other calculations to estimate the radioactive release from containment. In this accident physics cannot be analyzed separately from in-plant transport. 

Start the mud pump, running as slowly as possible, to pump fluid at a rate of 1.5 to 2.0 bbl/min. This reduces fluid friction resistance pressures to a minimum and pumps at minimum standpipe pressure for circulation. The standpipe pressure (for 1.5 to 2.0 bbl/min) can be found from standard fluid hydraulic calculations. 

Koch, R. and Kuzniar, J. (1966) International Chem. Eng. 6 (Oct.) 618. Hydraulic calculations of a weir sieve tray. 

Where a significant lift is required such as offshore, several options are available such as a shaft driven, hydraulic drive or electrical submersible pump. Shaft driven vertical turbine pumps historically have been used extensively offshore, but recent reliability improvement with electrical submersible pumps and hydraulic drive units have been eagerly accepted as they eliminate alignment problems, topsides weight and in some instances are less complex than the right angle engine driven vertical turbine units. Hydraulic calculations for offshore pump installations must remember to account for tide and wave fluctuations. 

Complete set of as-built drawings, including piping, electrical, and hydraulic calculations... 

Hydraulic calculations of water supply systems are critical to confirming their adequacy. Often such calculations are not current and, hence, flows and pressures are not readily available to be used as part of evaluations of system performance in cases where different events necessitate their use. 

Comparison of Helium-Based Water Ages and Hydraulically Calculated Ages... 

The paleohydraulic gradient changed continuously, a fact that has to be taken into account in hydraulic calculations of the ancient groundwater flow velocities. 

Mazor, E. and Nativ, R. (1992) Hydraulic calculation of groundwater flow velocity and age examination of the basic premises. J. of Hydrology 138, 211-222. 

Mazor, E. and Nativ R., (1994) Stagnant groundwaters stored in isolated aquifers implications related to hydraulic calculations and isotopic dating—a reply to a comment by T. Torgersen. J. of Hydrology, 154, 409-418. 

Mertes et al. (1993) estimated concentrations of suspended sediment in the surface waters of the Amazon River and adjacent floodplain from Landsat images. They documented patterns of decreasing concentration from the main channel onto the floodplain and through channels. Rates of sediment transport into the floodplain were estimated by combining the Landsat-derived sediment concentrations with hydraulic calculations (Mertes 1994). 

Confirm hydraulic calculations (line sizing) for compressor circuits and establish compressor differential. 

Confirm hydraulic calculations on all pump circuits and establish pump NPSH and minimum equipment elevations. 

One should note the above reference for more detailed hydraulic calculation methodology. 

The rigorous column models allow the design engineer to carry out tray sizing and hydraulics calculations for the basic types of distillation trays and for some types of random and structured packing. Different commercial simulators use different tray sizing correlations, but they all follow a method similar to that described in Chapter 11. 

Flooding is much more sensitive to vapor rate than to liquid rate. Trays can, however, definitely be flooded by high liquid rates. Prediction of maximum liquid capacity is based on hydraulic calculation of liquid backup in the downcomers. For low-foaming systems, it is often assumed that liquid backup cannot be more than half of the downcomer height, calculated as clear liquid. For high vapor density, e.g., S.Olb/ft the limiting backup is even less. 

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