Duplex Circular Wet Well (DCWW) lifting pump stations are utilized for pumping clear and solid-bearing liquid. Understanding the effect of design criteria on pump performance is important to minimize maintenance costs and maximize efficiency. There are currently no known full-scale laboratory studies that have been performed to investigate the overall design of DCWWs. The objective of the research was to evaluate the impact of various design criteria, such as internal geometry and operating conditions on the performance of DCWW pump stations and provide documentation and recommendations which will be used to augment the current Hydraulic Institute/American National Standard for Pump Intake Design (ANSI/HI 9.8-1998), (HI) guidelines. The research was conducted in two phases; Phase 1 consisted of performing a comparative analysis of the basic flow patterns within the wet well by means of Computational Fluid Dynamics (CFD), Phase 2 consisted of performing detailed evaluations of various design aspects on pump performance using a full-scale Physical Model constructed for the research. The CFD research provided indications regarding potential performance problems that may occur due to poor flow patterns and potential pump suction swirl, while the physical research provided a basis for determining the relative advantages of different designs. The physical research included the evaluation of general flow patterns, free-surface and subsurface vortices, air entrainment and pump suction swirl. Measurement of the steady state swirl within the pump showed unacceptable performance in accordance with the HI acceptance criteria. Swirl data collected under real-world dynamic operating conditions showed that the pump typically did not experience the adverse conditions indicated at steady state. Normal (symmetrical) pump orientation resulted in more favorable operation in terms of pump swirl and ingestion of entrained air than a coplanar (inline) condition. A minimum water elevation was established to minimize air-entrainment and swirl entering the pumps, reducing possible effects such as cavitation and vibration of the pump impeller. Air-core subsurface vortices were present under the pumps, requiring pump-cones to be installed. The collection of real-time dynamic data will allow design engineers to better understand actual pump performance under normal cycling and clean-out modes, reducing the operating time under unfavorable conditions and overall maintenance requirements.

This diploma thesis summarizes the necessary knowledge for the design of the pump station. It focuses on the choice of suitable pumps and control valves. It also provides information on mathematical optimization methods. By combining these two disciplines a program was created that selects the most suitable combination of pumps and valves for the assigned requirements. These can vary over time. The goal of optimization is to minimize initial and operating costs. The phenomena considered are: time-varying flow and head height, serial and parallel co-operation of pumps, throttling control, a change of characteristics for variable speed and temperature, suction height control, maximum motor output, loss in connection piping.

The advance in computational fluid dynamics in recent years has provided the opportunity for many fluid dynamic problems to be analyzed numerically. One such problem concerns the modeling of plunging water into a still water body, often encountered in pump stations. Air bubbles introduced into the system by the plunging jet can be a significant problem, especially when consumed into operating pumps. The classical approach to investigate the hydrodynamics of plunging jet in pump stations is by physical model studies. This approach is time consuming, tedious and costly. The availability of computational power today, along with appropriate numerical techniques, allows such phenomenon to be studied in a greater level of detail and more cost efficient. Despite the advantages of numerical studies, little attention has been devoted to solve the plunging jet and air transport problem numerically. In this current work, a 3-dimensional finite volume, Large Eddy Simulation (LES) code is developed to simulate these flow conditions. For turbulent flow, the large scale quantities were numerically resolved while the dynamic sub-grid scale model is used to model the small scale energy dissipations. The code also has the capability to handle free surface deformation, an important aspect in simulating the impact section of an impinging jet. Modeling of the air entrainment is performed numerically utilizing the information obtained from the hydrodynamics. Migration of air bubbles is modeled using the scalar transport equation, modified to account for the buoyancy of the bubbles. Instead of the typical Lagrangian schemes, which track individual air bubbles, air bubble dynamics are modeled in the form of concentrations. Modeling air bubbles in this manner is computational efficient and simpler to implement. For the air entrainment simulations, standard numerical boundaries conditions and empirical entrainment equations are used to provide the necessary boundary conditions. The developed model is compared with the literature, producing satisfactory results, suggesting that the code has an excellent potential of extending its application to practical industry practices.

Made available in DSpace on 2014-12-17T15:03:31Z (GMT). No. of bitstreams: 1 FabianaPLM_DISSERT.pdf: 3435369 bytes, checksum: eeb98ff1cae8e980fe5be54da04a6770 (MD5) Previous issue date: 2012-08-31 / The simulation of SES-Natal Ponta Negra: mitigation of environmental risks and predictive maintenance strategy was developed in the context of several operational irregularities in the pumping stations and sewage systems in the system Ponta Negra. Thus, the environmental risks and complaints against the company due to overflows of sewage into the public thoroughfare became common. This neighborhood has shown in recent years an increase of resident higher than the initial expectation of growth. In this sense presumed the large population growth and generation of sewers higher than expected, associated to the use of corrective maintenance and misuse of the system may be the main causes of operational failures occurring in the SES. This study aimed at analyzing the hydraulic behavior of SES Ponta Negrathrough numerical simulation of its operation associated to future scenarios of occupation. The SES Ponta Negra has a long lengthof collection networks and 6 pumping stations interconnected, being EE 1, 2, 4 coastal way, and beach Shopping interconnected EE3 to receives all sewers pumped from the rest pumping station and pumped to the sewage treatment station of neighborhood which consists of a facultative pond followed by three maturation ponds with disposal of treated effluent into infiltration ditches. Oncethey are connected with each other, the study was conducted considering the days and times of higher inflow for all lifts. Furthermore, with the aim of measuring the gatherer network failures were conducted data survey of on the networks. Thephysical and operational survey data was conducted between January/2011 and janeiro/2012. The simulation of the SES was developed with the aim ofdemonstrating its functioning, eithercurrently and in the coming years, based in population estimates and sewage flow. The collected data represents the current framework of the pumping stations of the SES Ponta Negra and served as input to the model developed in MS Excel ? spreadsheet which allowed simulating the behavior of SES in future scenarios. The results of this study show thatBeach Shopping Pumping Station is actually undersized and presents serious functioning problemsthatmay compromise the environmental quality of surrounding area. The other pumping stations of the system will reach itsmaximum capacity between 2013 and 2015, although the EE1 and EE3 demonstrateoperation capacity, even precariously, until 2017. Moreover, it was observed that the misuse of the network system, due to the input of both garbage and stormwater, are major factors of failures that occur in the SES. Finally, it was found that the corrective maintenance appliance, rather than predictive,has proven to beinefficient because of the serious failuresin the system, causing damage to the environment and health risks to users / A Simula??o do SES Ponta Negra- Natal: mitiga??o dos riscos ambientais e estrat?gia de manuten??o preditiva foi desenvolvida no contexto de diversas irregularidades operacionais nas esta??es elevat?rias e redes coletoras de esgoto no sistema de Ponta Negra. Com isso, os riscos ambientais e as denuncias contra a empresa de saneamento devido aos extravasamentos de esgotos em via p?blica se tornaram comuns. Esse bairro vem apresentando nos ?ltimos anos um aumento populacional muito maior do que a expectativa inicial de crescimento. Nesse sentido, sup?e-se o grande crescimento populacional e de gera??o de esgotos acima do esperado, atrelado ? utiliza??o de manuten??o corretiva e o mau uso do sistema podem ser as principais causas das falhas operacionais ocorridas neste SES. Esse estudo teve por objetivo analisar o comportamento hidr?ulico do SES de Ponta Negra a partir da simula??o num?rica do seu funcionamento associados ? cen?rios futuros de ocupa??o. O SES Ponta Negra apresenta quil?metros de redes coletoras e 6 esta??es elevat?rias interligadas, sendo a EE 1, 2, 4, Via Costeira e Praia Shopping interligadas a EE3, qual recebe todos os efluentes das demais elevat?rias e bombeia para a esta??o de tratamento de esgotos do bairro a qual ? constitu?da de uma lagoa facultativa seguida de 3 lagoas de matura??o com disposi??o dos efluentes tratados em valas de infiltra??o. Por serem interligadas entre si, o estudo foi realizado considerando os dias e horas de maior vaz?o afluente para todas as elevat?rias. Al?m disso, a fim de mensurar as falhas nas redes coletoras foram realizados levantamento dos dados de obstru??es nessas redes. O levantamento e coleta de dados f?sicos e operacionais foram realizados entre janeiro/2011 e janeiro/2012. A simula??o do SES foi desenvolvida, a fim de nos mostrar como esse est? funcionando atualmente, e como ir? funcionar nos pr?ximos anos, com base na estimativa populacional e de vaz?o de esgotos. Os dados coletados representam o quadro atual das esta??es elevat?rias do SES Ponta Negra e alimentaram o modelo num?rico desenvolvido em planilha eletr?nica MS Excel? que permitiu simular o comportamento do SES em cen?rios futuros. Os resultados obtidos neste estudo mostram que a elevat?ria Praia Shopping j? est? subdimensionada e apresenta falhas graves de funcionamento que compromete a qualidade do ambiente os aspectos ambientais da ?rea onde est? inserida. As demais elevat?rias do sistema atingir?o sua capacidade m?xima segura de bombeamento entre os anos de 2013 e 2015, embora a EE 1 e EE 3 tenham a capacidade de operar, ainda que de forma muito prec?ria, at? o ano de 2017. Al?m disso, observou-se que o mau uso do sistema, com a entrada de lixo e ?gua de chuva na rede coletora, s?o fatores determinantes para as falhas que ocorrem no SES. E finalmente, constatou-se que a utiliza??o de manuten??o corretiva, em vez da preditiva, no sistema como um todo tem se mostrado altamente ineficiente causando graves falhas no sistema, gerando com isso danos ao meio ambiente e riscos sanit?rios aos clientes

Diploma thesis presents various methods of energetic utilization of wastewater. It shows that wastewater is source of heat energy that has not been used yet. The thesis focuses mainly on heat recovery from wastewater from sewer bypass by modular heat exchangers. Design of heating of polyfunctional building from bypass from main sewer in Brno is developed. The main finding is that wastewater as low potential source of energy can together with heat pump be not only used for heating and heating of domestic hot water but also for cooling of polyfunctional object. Part of work is also technical-economical assessment by the NPV method.

Thesis (MScEng)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Various design guidelines have been published over the past four decades to calculate the minimum submergence required at pump intakes to prevent vortex formation. These design guidelines also require the suction bell to be located not higher than 0.5 times the suction bell diameter (D) above the floor. Sand trap canals are an integral part of large river abstraction works, with the pump intakes located at the end of the sand trap canals. The canals need to be flushed by opening a gate, typically 1.5 m high, that is located downstream of the pump intake. This requires the suction bell be raised to not interfere with the flushing operation, which leads to the question – what impact does the raising of the suction bell have on the minimum required submergence? A physical hydraulic model constructed at 1:10 scale was used to determine the submergence required to prevent types 2, 5 and 6 vortices for prototype suction bell inlet velocities ranging from 0.9 m/s to 2.4 m/s, and for suction bells located at 0.5D, 1.0D and 1.5D above the floor. The tests were undertaken for four suction bell configurations with a conventional flat bottom suction bell, fitted with a long radius bend, being the preferred suction bell configuration in terms of the lowest required submergence levels. The experimental test results of the preferred suction bell configuration were compared against the published design guidelines to determine which published formula best represents the experimental test results for raised pump intakes. It became evident from the experimental test results that the required submergence increased markedly when the suction bell was raised higher than a certain level above the floor. It was concluded that this “discontinuity” in the required submergence occurred for all the suction bell configuration types when the ratio between the prototype bell inlet velocity and the approach canal velocity was approximately 6.0 or higher. It is recommended that, for pump intakes with a similar geometry to that tested with the physical hydraulic model, critical submergence is calculated using the equation published by Knauss (1987), i.e. S = D(0.5 + 2.0Fr), if the prototype bell inlet velocity/approach canal velocity ratio is less than 6.0, and that the equation published by the Hydraulic Institute (1998), i.e. S = D(1 + 2.3Fr), can be used where the ratio, as determined with Knauss’ (1987) equation, exceeds 6.0. It is also recommended that prototype bell inlet velocities be limited to 1.5 m/s. / AFRIKAANSE OPSOMMING: Oor die afgelope vier dekades is verskeie ontwerpriglyne vir die berekening van minimum watervlakke, om werwelvorming by pompinlate te voorkom, gepubliseer. Hierdie ontwerpriglyne vereis dat die klokmond van die pompinlaat nie hoër as 0.5 keer die deursnee van die klokmond (D) bokant die kanaalvloer geleë moet wees nie. Sandvang kanale vorm ‘n integrale deel van groot riveronttrekkingswerke, met pompinlate wat aan die einde van hierdie kanale geleë is. Die kanale word aan die stroomaf kant van die pompinlaat voorsien met sluise sodat die kanale gespoel kan word. Hierdie sluise is tipies 1.5 m hoog. Dit is derhalwe nodig om die hoogte onder die klokmond dieselfde te maak as die hoogte van die sluis sodat die klokmond die spoelwerking nie beïnvloed nie. Die vraag is egter – wat is die impak op die minimum vereiste watervlakke indien die klokmond op ‘n hoër vlak installeer word? ‘n Fisiese hidrouliese model met ‘n 1:10 skaal is gebruik om die minimum watervlakke te bepaal waar tipes 2, 5 en 6 werwels aangetref word vir prototipe inlaatsnelhede van 0.9 m/s tot 2.4 m/s en klokmond hoogtes van 0.5D, 1.0D en 1.5D bokant die kanaalvloer. Vier klokmond konfigurasies is getoets. Die minimum vereiste watervlakke was die laagste vir die tradisionele plat klokmond met ‘n lang radius buigstuk en was dus die voorkeur klokmond. Die eksperimenttoetsresultate vir die voorkeur klokmond is met die gepubliseerde ontwerpriglyne vergelyk om te bepaal watter van die ontwerpsriglyne van toepassing sal wees vir verhoogde klokmond installasies. Uit die eksperimenttoetsresultate is dit duidelik dat die vereiste watervlakke skielik verhoog sodra die klokmond installasie ‘n seker hoogte bokant die kanaal vloer oorskry. Daar is bevind dat hierdie verskynsel by al vier klokmond konfigurasies voorkom sodra die verhouding tussen die prototipe klokmond inlaatsnelheid teenoor die snelheid in die kanaal hoër as 6.0 is. Daar word aanbeveel dat die minimum vereiste watervlak vir pompinlate met dieselfde geometrie as die fisiese model, met Knauss (1987) se vergelyking bereken word, naamlik S = D(0.5 + 2.0Fr), waar die snelheidsverhouding tussen die klokmond en kanaal 6.0 nie oorskry nie, en dat die vergelyking gepubliseer deur die Hydraulic Institute (1998), S = D(1 + 2.3Fr), gebruik word waar die snelheidsverhouding 6.0, so bereken met Knauss (1987) ser vergelyking, wel oorskry. Die prototipe klokmond inlaatsnelheid moet ook beperk word tot 1.5 m/s.

The diploma thesis is focused on Storm water management in urban areas. The first task for processing thesis was to arrange meeting with MČ Brno - Bohunice Ing. Antonín Crha, who has provided necessary information about the targeted location the and the reservoir for accumulation of rainwater collected. The practical part of the thesis is to capture the rainwater drainage in the existing rainwater sewerage system using the newly built pumping station and then pumping into the existing, unused reservoir. Accumulated water in the reservoir is planned to be used for the needs of the city, gardeners and other customers. The first part of the diploma thesis describes the management of refined water in the Czech Republic, Denmark and Germany. The first part also provides description of measures and technologies for the management of rainwater. Finally, there is description of the pumping station and borehole objects and the program for calculating the rainfall from the urbanized area. In the practical part of the diploma thesis the selected variants are described, rewarded and evaluated. The diploma thesis deals with two variants, that are guided along the same route, with the difference of the construction of the drilled well in the second variant. Both variants are handled by pumping. The option of the gravity inflow was rejected because of the large countersink of rainwater sewerage.

The diploma thesis is focused on Storm water management in urban areas. The first task for processing thesis was to arrange meeting with MČ Brno - Bohunice Ing. Antonín Crha, who has provided necessary information about the targeted location the and the reservoir for accumulation of rainwater collected. The practical part of the thesis is to capture the rainwater drainage in the existing rainwater sewerage system using the newly built pumping station and then pumping into the existing, unused reservoir. Accumulated water in the reservoir is planned to be used for the needs of the city, gardeners and other customers. The first part of the diploma thesis describes the management of refined water in the Czech Republic, Denmark and Germany. The first part also provides description of measures and technologies for the management of rainwater. Finally, there is description of the pumping station and borehole objects and the program for calculating the rainfall from the urbanized area. In the practical part of the diploma thesis the selected variants are described, rewarded and evaluated. The diploma thesis deals with two variants, that are guided along the same route, with the difference of the construction of the drilled well in the second variant. Both variants are handled by pumping. The option of the gravity inflow was rejected because of the large countersink of rainwater sewerage.

This thesis deals with plumbing in the hotel. The theoretical part is devoted to pumping tech-nology and the internal pressure of the water mains in high buildings. The work presents different variants of a possible solution in a given speciality. Project part solves sanitary equipment installation in the variant selected in the given building.

I detta arbete utvärderas och jämförs de i dagsläget aktuella teknikerna för automatisering av avloppspumpstationer. Utifrån undersökningen kommer en rekommendation av ett system göras som sedan ska kon-strueras och monteras ihop. Arbetet visar att trots energivinsterna som en extra investering i form av reglering ger så lönar det sig sällan om man inte byter pump samtidigt. Vid byte av pump kan man välja en pump som klarar det maximala flödet men samtidigt arbetar med högst effektivitet vid det vanligaste flödet. Då pumpar i avloppstationer ofta är överdimensionerade med avseende på det vanligaste flödet betyder en nedreglering att pumpen hamnar för långt bort från konstruktions-punkten. Pumpen får då sämre verkningsgrad och efter en viss punkt klara pumpen att inte av att överstiga det statiska motståndet och där-med inte skapa något flöde alls. Av dessa anledningar rekommenderas av/på-styrning vilket är den ledande tekniken idag / In this report the currently leading technologies for automation of sewage pump stations will be evaluated and compared. Based on this comparison a recommendation of a design will be done and the chosen control system will finally be assembled in a cabinet. The report shows that even thou there are energy savings to be done by using variable frequency drives it is rarely possible unless pumps are changed at the same time. When pumps are changed at the same time you have the opportunity to pick a pump that can handle the maximum inflow but at the same time have its best efficiency  point at lower speed. Pumps in sewage pump stations are often over dimensioned with regards to the most common inflow, lowering the speed will in this case result in lower efficiency and more losses. At one point the pump will not be able to overcome the static pressure in the system and will fail to produce any flow. Due to these reasons on/off control will be recommended which also is the most common method of today.