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Traditional systems of drinking water delivery
Published in Thomas Bolognesi, Francisco Silva Pinto, Megan Farrelly, Routledge Handbook of Urban Water Governance, 2023
Raziyeh Farmani, Chris Sweetapple
Different types of pumps are available, with centrifugal pumps being the most commonly used in water distribution systems. These are easy to install and operate, are low cost, and can be operated under a variety of conditions. Specific types of centrifugal pump include axial-flow, radial-flow, and mixed-flow. Radial-flow pumps provide (relatively) low capacity and high head, and, in water distribution systems, they may be used where there is an elevation difference between supply and distribution areas, to enable water to be transferred from low elevation to high elevation during low energy tariff times and used during peak demand time. Axial-flow pumps, conversely, provide high capacity but low head, and they can be used where there is relatively little difference in elevation – for example, transferring raw water from a reservoir to a treatment plant. Mixed-flow pumps deliver a moderate flow of water with medium head.
Pumps for Groundwater Lowering Duties
Published in Pat M. Cashman, Martin Preene, Groundwater Lowering in Construction, 2020
This pump comprises a centrifugal pump of the volute type combined with a separate vacuum pump. A centrifugal pump is a rotodynamic pump where an impeller rotating at high speed pushes water radially outward. The water flung out from the impeller is directed through the tangential outlet of a curved casing (the volute) enclosing the impeller, where the kinetic energy of the water is converted to pressure. Water leaving the central eye of the impeller creates suction, drawing more water to the pump. The separate vacuum pump removes air from the pipework upstream of the impeller to allow the pump to quickly self-prime.
Fluid Transport in Thermal Energy Systems
Published in Steven G. Penoncello, Thermal Energy Systems, 2018
In the design of a fluid piping system, one of the tasks of the engineer is to select a pump (or pumps) that provides the required flow rate through the piping system. There are a wide variety of pumps available designed for specific applications. However, they can be classified into one of two categories; positive displacement and dynamic. The main focus of this chapter will be on centrifugal pumps, a type of dynamic pump, because they are the most commonly used in industrial applications. Even among centrifugal pumps, there are many different types including end suction, submersible, split case, etc. These different pump designs are made to handle different types of fluids, system pressures, flows, and other conditions. The final selection of a pump must take into account all of these factors. Once the techniques of selecting a centrifugal pump are understood, they are easily transferrable to other types of pumps.
A comprehensive review on fault detection and analysis in the pumping system
Published in International Journal of Ambient Energy, 2022
Nabanita Dutta, Palanisamy Kaliannan, Shanmugam Paramasivam
The movement of fluid from one location to another is the primary function of the pumping system. A rotating impeller is used in the pump to move the fluid using centrifugal force. Pumps can be categorised in various ways, but according to the working principle, they are categorised into two types: rotodynamic pump and positive displacement pump. Centrifugal pump is primarily referred to under the significant contribution of the rotodynamic pumping system and used in large scale in industrial applications, whereas positive displacement pump is more efficient than a centrifugal pump. Still, it has a minimum flow rate and low-pressure head, so it is frequently not used in large industries (Shankar et al. 2016). Polymer , plastic , lubrication oil, small chemical industries where the demand for the pump is low, only positive displacement pumps are used (Figure 1). Pumps are operated in different applications, and according to operational activities, centrifugal pumps are of two types: single-stage pump and multi-stage pump (Waide and Brunner 2011).
Surrogate-based design optimization of a centrifugal pump impeller
Published in Engineering Optimization, 2022
Ashutosh Kumar Jaiswal, Md. Hamid Siddique, Akshoy Ranjan Paul, Abdus Samad
Figure 13 shows that the force acting on the blade of the optimized impeller is lower than for the reference impeller. The force acting on the blade impeller is responsible for the required input power of the pump. The input power comprises two components: one is due to the kinetic head [], where Δv is the relative velocity within the impeller due to the no-slip condition (frictional flow) over the blade, and the other is due to the potential head, which is obtained when is converted into the pressure head. The kinetic head decreases with the intensification of the discharge, which corresponds to the radial velocity component, whereas the potential head increases with the increase in the discharge, which corresponds to the tangential component of velocity (Zhang et al. 2016). Since the speed of the pump is constant, the tangential velocity component remains constant. Thus, there is no change in the potential head and the corresponding input power component. While the increase in the radial velocity component decreases the kinetic head, this decreases the force acting on the blade, and the same can be found with Equation (15). The decrease in forces over the impeller blades reduces the power needed (which can be analysed with Equation 16) by the optimized impeller in comparison to the reference impeller and thus, ultimately, improves the efficiency of the centrifugal pump.
Shape optimization and uncertainty assessment of a centrifugal pump
Published in Engineering Optimization, 2022
Alessia Fracassi, Remo De Donno, Antonio Ghidoni, Pietro Marco Congedo
Centrifugal pumps are widely used in many industrial fields, such as agriculture, the automotive industry, the chemical industry, power generation and bio-engineering, and are characterized by considerable differences in the required pressure ratio and flow rate. Many free geometric parameters can influence their performance, making the design phase very complex and time-consuming. The design can be accomplished following different approaches: (i) experimental, where prototypes and previous models are modified with a trial-and-error method; and (ii) numerical, where Computer-Aided Design/Computation Fluid Dynamics (CAD/CFD) tools are applied to the design and analysis. The former approach can be too expensive, while in the latter case, the computed results are not easily related to the pump's performance. However, the exponential growth of the available computational resources has paved the way for the automation of conventional design processes by coupling CFD solvers and optimization algorithms. This methodology results in a systematic design process, partially based on experience and faster than traditional approaches, that requires continuous refinement of components' geometry.