Semi-Ebonite. Part 2

1936 ◽  
Vol 9 (3) ◽  
pp. 468-485
Author(s):  
P. A. Gibbons ◽  
F. H. Cotton
Keyword(s):  
Experimental Method ◽  
Original Form ◽  
Considerable Difficulty ◽  
Outlet Tube ◽  
Test Pieces ◽  
Volatile Products ◽  
Inlet Tube ◽  
Frequent Reference ◽  
Conical Flask

Abstract In Part 1 (Rubber Chem. and Tech., 8, 554 (1935)) frequent reference was made to the volatile products emitted during the aging of semi-ebonite under different conditions. In this section an experiment is described wherein the various products were detected and some attempt made to estimate the relative amounts of each. The experiment in its original form presented considerable difficulty, and many disappointments were experienced before a modified apparatus was finally adopted. Experimental Method.—Eight test-pieces, one from each of the accelerated cures (see Part 1), were cut to a convenient size, six inches by one inch. The test-pieces were carefully weighed and their thickness determined as the average of several readings on the micrometer. The strips were suspended from a bent glass rod projecting from a cork-bearing inlet and outlet tubes (see Fig. 5). The cork was then inserted in a clean conical flask and the latter sealed with wax until it withstood a considerable vacuum. The flask was placed in a Geer oven automatically maintained at 70° C. The outlet tube was attached to an absorption train and the inlet tube to a purifying train.

Analysis and Modification on Blockage Problem of BBD Double Inlet and Outlet Tube Mill Separator

2013 ◽  
Vol 805-806 ◽  
pp. 1751-1754
Author(s):  
Qi Qin ◽  
Chun Yu Wang ◽  
Li Ming Ren ◽  
Ming Feng Xu ◽  
Lei Wang ◽  
...  
Keyword(s):  
Tube Mill ◽  
Outlet Tube ◽  
Article Analysis ◽  
Reform Scheme ◽  
The Relationship

This article analysis the relationship between BBD inlet and outlet tube mill separator blockage and the boiler's safety-economy, finds out the cause of the separator blockage, puts forward the corresponding reform scheme, then the retrofit scheme after implementing separator blockage problem.

Performance of Oil Separator According to the Depth of the Outlet Tube

2015 ◽  
Author(s):  
Seongil Jang ◽  
Joon Ahn ◽  
Si Hyung Lim
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Pressure Drop ◽  
Separation Efficiency ◽  
Lubricating Oil ◽  
Tube Length ◽  
Working Fluid ◽  
Energy Losses ◽  
Refrigeration System ◽  
Outlet Tube

Recent years have witnessed a growing concern over saving energy because of global warming issues and energy price hikes caused by increased oil prices. The need to improve energy efficiency to reduce energy consumption has been raised. Refrigeration systems are also expected to have their energy efficiency improved. A refrigeration system’s the compressor uses lubricating oil. Lubricating oil, along with refrigerant, circulates in a refrigeration system. During this process, the pressure drop increases, and the heat transfer coefficient decreases. Moreover, insufficient lubricant may incur a decrease in performance and damage to a compressor. Therefore, an oil separator is used to separate the lubricant and return it to the compressor. Since an oil separator causes an additional pressure drop, energy consumption should be decreased by increasing the oil separator’s separation efficiency and decreasing the pressure drop. The recent increase in development of large-scale buildings such as skyscrapers and large supermarkets has also increased the demand for large refrigeration machines. At the same time, refrigeration piping is becoming longer, and refrigerant must circulate up to the highest points. A high-pressure head and long piping configuration inevitably increase the quantity of lubricant left on the pipe wall, which in turn increases the loss of lubricants. The increased length and fall height for lubricants to circulate with refrigerant increase the related energy loss. In order to use a compressor in a high-head long-piping refrigeration system, the separation efficiency of the oil separator must be improved. Doing so will also reduce energy losses. Even with an improved separation efficiency, however, an increased pressure drop means additional energy losses. Thus, an oil separator with high separation efficiency and low pressure drop should be designed. So using the Numerical analysis, designed a new oil separator. A series of numerical simulation has been carried out to study peformance of a cyclone type oil separator, which is designed for the compressor of a refrigeration system. Working fluid is R22, which is a typical refrigerant, and mineral oil droplet is supplied. Depending on the outlet tube length, separation efficiency varies from 98.74 to 99.25%. Considering both of the separation efficiency, outlet tube length of the separator has been designed as 158 mm and oil separator length is 310mm.

scholarly journals FLOATING SIPHON WITH A CONSTANT HEAD

1974 ◽  
Vol 5 (2) ◽  
pp. 98-107
Author(s):  
RICHARD THOMSEN
Keyword(s):  
Water Level ◽  
Water Surface ◽  
Surface Registration ◽  
Registration System ◽  
Outlet Tube ◽  
Discharge Water ◽  
Constant Rate ◽  
Constant Head ◽  
Better Than

A floating siphon made up of concentric tubes is proposed as a reliable and inexpensive device to discharge water from a reservoir tank at a constant rate independent of the water level in the tank, provided the siphon is discharged freely into the atmosphere. By adjusting the opening area in the outlet tube continuously, any constant discharge can be obtained. With simple aids the siphon has been calibrated to work with an accuracy better than 5 ‰. By means of an electric Water Surface Registration System it is proved that the variation in discharge is better than 1 ‰ at a discharge of 0.3–2.4 1/s.

scholarly journals Numerical Study on Separation Performance of Cyclone Flue Used in Grate Waste Incinerator

Processes ◽  
2019 ◽  
Vol 7 (12) ◽  
pp. 866 ◽  
Author(s):  
Dong-mei Chen ◽  
Jing-yu Ran ◽  
Jun-tian Niu ◽  
Zhong-qing Yang ◽  
Ge Pu ◽  
...  
Keyword(s):  
High Temperatures ◽  
Low Temperatures ◽  
Numerical Study ◽  
Heating Surface ◽  
Tube Diameter ◽  
Separation Performance ◽  
Waste Incinerator ◽  
Outlet Tube ◽  
Comprehensive Performance ◽  
Vortex Finder

The traditional treatment of waste incineration flue gas is mostly carried out in low temperatures, but there are some problems such as corrosion of the heating surface at high and low temperatures, re-synthesis of dioxins, and low efficiency. Therefore, it is necessary to remove the pollutants at high temperatures. For the grate waste incinerator, this study proposes an adiabatic cyclone flue arranged at the exit of the first-stage furnace of the grate waste incinerator to pre-remove the fly ash at high temperatures, so as to alleviate the abrasion and corrosion of the tail heating surface. In this paper, computational fluid dynamics (CFD) method is applied to study the performance of a cyclone flue under different structural parameters, and the comprehensive performance of the cyclone flue is evaluated by the technique for order preference by similarity to an ideal solution (TOPSIS) method. The results show that particle separation efficiency increases at first and then decreases with the increase of the vortex finder length, the vortex finder diameter, and the distance between vortex finder and gas outlet tube, while it decreases with the increase of the gas outlet tube diameter. The pressure drop increases with the increase of the vortex finder length, and the vortex finder diameter, while decreases with the increase of the distance between the vortex finder, the gas outlet tube, and the gas outlet tube diameter. In the scope of this study, when h1/a = 1.1, D1/A = 0.33, h2/A = 1.5, and D2/A = 0.50, the comprehensive performance of the cyclone flue is much better.

scholarly journals Influence of perforation and sound-absorbing material filling on acoustic attenuation performance of three-pass perforated mufflers

2018 ◽  
Vol 10 (1) ◽  
pp. 168781401774801 ◽  
Author(s):  
Hongpu Huang ◽  
Zhenlin Ji ◽  
Zhuoliang Li
Keyword(s):  
Finite Element Method ◽  
Transmission Loss ◽  
The Finite Element Method ◽  
Frequency Range ◽  
Acoustic Attenuation ◽  
Pressure Drops ◽  
Outlet Tube ◽  
Middle Chamber ◽  
Absorbing Material ◽  
Perforated Tube

The finite element method is employed to calculate the transmission loss of three-pass perforated reactive and hybrid mufflers. The effects of perforated tubes and bulkheads on the transmission loss of three-pass reactive mufflers are investigated numerically. Two types of hybrid mufflers are considered, and the effects of sound-absorbing material filling and packed outlet tube on the acoustic attenuation performance of mufflers are analyzed. The perforations of the tubes and bulkheads and sound-absorbing material filling are demonstrated to have significant influence on the acoustic attenuation behaviors of the mufflers. The perforation of the tubes and bulkheads may shift the resonance from the low- to middle-frequency range. The sound-absorbing material filling in the middle chamber improves the acoustic attenuation performance at middle to higher frequencies and provides a relatively flat and broadband acoustic attenuation. It is found that the solid inlet or outlet tube replacing the perforated tube and sound-absorbing material filling in the middle chamber increases the pressure drops, while the rest configurations change the pressure drops slightly.

Hydrology models DRAINMOD and SWIM applied to large soil lysimeters with artificial drainage

Soil Research ◽  
1998 ◽  
Vol 36 (5) ◽  
pp. 783 ◽  
Author(s):  
G. F. Barkle ◽  
T. N. Brown ◽  
D. J. Painter ◽  
P. L. Singleton
Keyword(s):  
Soil Water ◽  
Standard Error ◽  
Water Distribution ◽  
Richards Equation ◽  
Model Parameters ◽  
Controlled Drainage ◽  
Outlet Tube ◽  
Soil Water Distribution ◽  
Large Soil ◽  
Soil Lysimeters

Two hydrological models, which used different methods to determine the soil water distribution in a soil profile, were evaluated against 4 years of data from large soil lysimeters. SWIM determines soil water distribution from a finite difference implementation of the Richards" equation. DRAINMOD uses a soil-specific relationship between the air volume in a profile and the watertable height to locate the depth to the saturated zone. An ‘equilibrium’ relationship between soil water tension and depth is then assumed to distribute the soil water in the unsaturated zone. Predicted values and measured values for drainage and watertable heights were compared for 3 drainage treatments. The drainage in the lysimeters was achieved by installing an outlet tube on the slowly permeable layer at 0·75 m from the soil surface. The conventional drainage treatment allowed gravity drainage to occur directly from this drainage outlet tube. The other 2 drainage treatments employed controlled drainage, where a step (or weir) is installed in the outlet tube. No drainage can occur from the lysimeters until the water table within the lysimeters reaches the step height. Two different step heights provided 2 controlled drainage treatments. Independently determined model parameters were used without additional calibration for the analysis. Both models performed well. DRAINMOD over-predicted the 4-year cumulative drainage for all treatments, with the largest error being 7%. SWIM conversely under-predicted cumulative drainage, with a maximum error of 16%. The standard error of estimation for the watertable height over the full 4-year data period was lower for SWIM, ranging from 0 ·06 to 0·12 m. DRAINMOD’s standard error over the same period for the watertable height ranged from 0·09 to 0·21 m. Generally, error values from this work were smaller than comparable values from other studies. The hydrology of the lysimeters where there was no lateral inflow, surface runoff, or deep seepage losses, coupled to an essentially 1-dimensional flow domain, probably contributed to the lower errors. Furthermore, limitation of the maximum watertable heights by the controlled drainage regime in the lysimeters also reduces the maximum possible magnitude of the standard error term.

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