Elevated Reservoir Research Articles

Extended Period Simulation of Water Systems—Part B

A procedure is presented for simulating the behavior of a water distribution system over time. The extended period simulation capability is an important consideration in both planning and operation of water distribution systems. The important aspects of the paper are: (1)The application of efficient sparsity oriented programming techniques for the static solution of network nodal equations using a modified Newton-Raphson procedure; and (2)the development of an integration scheme to link several statis solutions, each representing an interval of time, to changes in water levels in elevated storage reservoirs, in pumping schedules and demand patterns. Only the theoretical considerations are and demand patterns.

Extended Period Simulation of Water Systems—Part A

A procedure is presented for simulating the behavior of a water distribution system over time. The extended period simulation capability is an important consideration in both planning and operation of water distribution systems. The important aspects of the paper are: (1)The application of efficient sparsity oriented programming techniques for the static solution of network nodal equations using a modified Newton-Raphson procedure; and (2)the development of an integration scheme to link several statis solutions, each representing an interval of time, to changes in water levels in elevated storage reservoirs, in pumping schedules and demand patterns. Only the theoretical considerations are and demand patterns.

Optimization of Water Distribution Network Systems

A new method for a workable optimum cost solution of pipe sizes of various branches of a water distribution network with given geometry, peak demand values, and specified terminal pressure heads has been developed incorporating pipe cost function. A correction factor for flow has also been derived which, when algebraically added successively to the assumed flow values of pipes in a loop during an iteration process, results in convergence towards the solution. As theoretical least-cost solution results in the formation of a tree network, a workable optimum condition has been considered by fixing a minimum size of pipes. The integrated total cost of the system including capital and recurring cost of pumping station, elevated reservoir, and pipes has been optimized to obtain optimum inlet pressure head, pressure surface, and position of elevated reservoir for a given network. The applicability of the approach has been illustrated with a problem.

On the Validity of the Master Equation for Internal Relaxation at High Densities

The validity of the collisional master equation for the relaxation of molecular internal degrees of freedom in a high-density reservoir of inert particles is examined using the generalized master equation for this system. When the hypotheses of the “Markovian approximation” to this equation are examined, it is found that they are invalidated by correlated collision processes which occur at elevated reservoir densities. At densities where the mean free time is long compared to a characteristic frequency of the internal states and the duration of a collision, the usual multiple collision theory master equation is shown to hold.

Optimization in Design of Hydraulic Network

A new method termed as equivalent diameter method for the direct least-cost solution of pipe sizes of the different branches of the network consisting of pumps, elevated service reservoir and the n...

Mechanism of anti-shock effect of glucocorticoid in hemorrhagic shock in rabbit.

It was shown that the extreme susceptibility of adrenalectomized rabbits to hemorrhagic hypotension was mainly due to the absence of glucocorticoid.‘Take-up’ of shed blood in an elevated reservoir proceeded far earlier and more rapidly than in the non-adrenalectomized rabbit. This was accompanied by progressive diminution of pulse pressures, while the cardiac rate was reduced. At autopsy, no blood pooling was noticed except that due to acute right heart failure. Examination of right ventricular pressures revealed the presence of progressive secondary rise in systolic and diastolic pressures indicating an increase in the resistance of the pulmonary circuit. Pretreatment with physiological dose of Cortisone prevented these changes and inhibited the rapid progress of ‘take-up’. The significance of glucocorticoid therapy in hemorrhagic hypotension in rabbits which differed from that in dogs has been discussed.

Epinephrine levels in the peripheral blood during irreversible hemorrhagic shock in dogs.

Dogs were bled to a mean arterial pressure of 40 mm. Hg until 10 per cent of the shed blood had automatically reinfused from an elevated reservoir. The remaining blood was then rapidly infused intravenously. The procedure was fatal to all 13 dogs. Arterial blood epinephrine levels were followed during the time of hemorrhage and the post-hemorrhagic survival period in 9 of these animals. Arterial blood epinephrine levels in the 9 dogs increased from control values of less than one µg./L. to a maximum of 29 µg./L. during early hemorrhage, and then decreased during the period of spontaneous reinfusion to 7.5 µg./L. After complete reinfusion the blood pressure returned to normal, and epinephrine disappeared from the circulation. The blood pressure then gradually failed under normovolemic conditions, and the animals died in shock after an average of 220 minutes. Blood samples obtained immediately before death when the mean arterial pressure was 45 mm. Hg contained only 3.5 µg./L. epinephrine.

Tentative Recommended Practice for Painting and Repainting Elevated Steel Water Storage Tanks, Standpipes, and Reservoirs

<i>Tentative Recommended Practice for</i> Painting and Repainting Elevated Steel Water Storage Tanks, Standpipes, and Reservoirs

Standard Specifications for Elevated Steel Water Tanks, Standpipes and Reservoirs

Journal AWWAVolume 41, Issue 4 p. 358-396 Article Standard Specifications for Elevated Steel Water Tanks, Standpipes and Reservoirs First published: 01 April 1949 https://doi.org/10.1002/j.1551-8833.1949.tb15100.xCitations: 1AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume41, Issue4April 1949Pages 358-396 RelatedInformation

Tentative Recommended Practice for Inspecting, Repairing and Repainting Elevated Steel Water Storage Tanks, Standpipes and Reservoirs

Journal AWWAVolume 40, Issue 10 p. 1101-1117 Article Tentative Recommended Practice for Inspecting, Repairing and Repainting Elevated Steel Water Storage Tanks, Standpipes and Reservoirs First published: 01 October 1948 https://doi.org/10.1002/j.1551-8833.1948.tb15058.xAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Volume40, Issue10October 1948Pages 1101-1117 RelatedInformation

Revisions in Standard Specifications for Elevated Steel Water Tanks, Standpipes and Reservoirs

Revisions in Standard Specifications for Elevated Steel Water Tanks, Standpipes and Reservoirs

Tentative Standard Specifications for Elevated Steel Water Tanks, Standpipes and Reservoirs

<i>Tentative</i> Standard Specifications <i>for</i> Elevated Steel Water Tanks, Standpipes and Reservoirs

An Alternative to the Severn Barrage

IN supplying electrical energy economically, it is very desirable that all the machines in use should be running as nearly as possible continuously at their full load. The overhead costs divided by the output will thus be a minimum. If the machinery were only to run for one hour per day at full load and for 23 hours per day at a tenth load, nine-tenths of the machines would be lying idle most of the time. If a cheap method of storing electrical energy could be invented, we could effect great economies by having only a few machines, all of which would run fully loaded. In an article in the Times of August 24, Mr. J. W. Meares criticises the Severn barrage scheme from this point of view. Between the ebb and flow of the tide there are periods when the turbines must necessarily be inactive, and hence the load on them would be far from being continuous. The chief item in the cost of the scheme is the dam itself. Provision would probably be made for utilising the fortnightly spring tides, and so the load would have a fortnightly fluctuation superposed on the usual twice-a-day one. Mr. Meares suggests that, without using the tides at all, a great deal of electric energy might be generated and stored at some of our steam driven stations. All that would be necessary is to use them to pump water to some elevated reservoir, one situated on a hill for example. At times of peak load this water could be used to drive turbo-electric sets, the electricity generated being transmitted to help supply the load. At first sight it appears a much cheaper method of helping the national supply than utilising the tides. In many cases also the necessary works could be completed in a fraction of the time required for the Severn barrage. It is satisfactory to remember that when the price of coal gets much dearer, we have always tidal power in reserve.

Recent Hydro-Electric Developments in the Alps and the Apennines

THE widely extended and systematic exploita-tion within recent years of the valuable water power resources of Switzerland and Italy, hitherto lying latent among the mountain chains of the Alps and the Apennines, is one of the most striking features in connexion with the modern industrial and commercial developments of the countries in question, and it has been, and is being, attended by economic repercussions affecting various nation-alities, including our own. Coal, the usual source of energy for power purposes where it can be mined, is lacking as a natural deposit, and, in the past, manufacturers using mineral fuel have had to rely in the main on importations from abroad, a very considerable portion of which came from Great Britain (South Wales and the Tyne district). The acute experience during the War, when these external supplies were cut off, brought home to the Swiss and Italian peoples the necessity of finding some internal means of making good a deficiency which tended to hamper, and even to paralyse, their industrial activities and placed them at the mercy of foreign interests. Not surprisingly, their attention was directed to the great potential value of the streams and lakes in the mountainous districts, where an untold quantity of water lay ready for utilisation and was capable, in a very large measure, of meeting commercial and industrial needs. These elevated reservoirs and mountain streams could be harnessed so as to produce electric current, which, in turn, could be distributed far and wide to suitable points of application.

The Water Supply of the Quad Cities

The Quad Cities (Davenport, Iowa, Rock Island, Moline and East Moline, Illinois), offer to the water works man a good field for observation. In our midst we have six distinct water departments four supplying filtered Mississippi River water and two well water. Three of the four use mechanical filters and the fourth pressure filters. In East Moline, Illinois, and Bettendorf, Iowa, they use deep-well water, pumped into elevated tanks. Davenport. Unlike the Moline, Rock Island, East Moline and Bettendorf plants, the Davenport water works is owned by a private corporation operating under a franchise. The source of supply is the Mississippi River the intake being located on the north side of the main channel. The method of operation is by gravity from river to screen chamber and intake well; pumping from intake well to settling basin; pumping from settling basin through filters to low-service mains and elevated storage reservoir; pumping from storage reservoir into high-service mains. The water supplied to the low-service mains is pumped twice; the water supplied to the high-service mains is pumped three times. The total quantity is about 4,000,000 gallons per day, of which about 1,500,000 gallons are pumped into the high mains. The works were built in 1873 and have been under the same management since that time. The main idea in the mind of the management has been service first. This is shown in many ways. For instance, filters were installed in 1891, which was early in the history of mechanical filters, and modern improvements such as large sedimentation basins, air wash and sterilization have been added as soon as shown to be practicable. Then there is the great advantage of two pumping stations in time of large fires, the reservoir pumping station supplying water down hill for fires in mercan-