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Water/Wastewater Math Operations
Published in Frank R. Spellman, Handbook of Water and Wastewater Treatment Plant Operations, 2020
Force, pressure, and head are important parameters in water and wastewater operations. Before we study calculations involving the relationship between force, pressure, and head, we must first define these terms:Force—It is the push exerted by water on any confining surface. Force can be expressed in pounds, tons, grams, or kilograms.Pressure—It is the force per unit area. The most common way of expressing pressure is in pounds per square inch (psi).Head—It is the vertical distance or height of water above a reference point. Head is usually expressed in feet. In the case of water, head and pressure are related.
The Power of Shape
Published in Patrick Hossay, Automotive Innovation, 2019
Fundamental to this effort is an understanding of the relationship between air speed and pressure. In fluid dynamics, Bernoulli’s Principle says that when a fluid increases in speed, it decreases in pressure. So, if air is forced through a narrow channel, called a venturi, it will speed up as the channel narrows. With a smaller cross-sectional area, molecules need to speed up to make it through the restriction; much like you might be pushed quickly through a narrow doorway as a slow-moving crowd exits a stadium. The upper surface of a car functions in a similar way. By forcing the air to travel the longer distance over the top of the car, the speed increases. And, according to this principle, as the speed increases the pressure decreases (Image 8.3). Since the bottom of the car is flat, this effect causes a net negative pressure on the top of the car resulting in a lifting force on the car.
Wind Energy Harvesting System
Published in Yen Kheng Tan, Energy Harvesting Autonomous Sensor Systems, 2017
The aerodynamic effect of airflow on the piezoelectric wind energy harvester is described based on a well-known fluid mechanic principle: Bernoulli’s principle. Bernoulli’s principle states that in fluid flow, an increase in velocity occurs simultaneously with a decrease in pressure. This principle is a simplification of Bernoulli’s equation, which states that the sum of all forms of energy in a fluid flowing along an enclosed path is the same at any two points in that path. The fluid can be either a liquid or a gas, but for Bernoulli’s principle to be applicable, the fluid is assumed to have the following qualities [75]: Fluid flows smoothly.Fluid flows without any swirls (also known as eddies).Fluid flows everywhere throughout the pipe (which means there is no “flow separation”).Fluid has the same density everywhere (it is “incompressible” like water).
Experimental investigations on an inline low head axial flow turbine with hydrofoil shaped vanes
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2022
Vimal Patel, Vikram Rathod, Chirag Patel
In Figure 8, the specifics of the rotor layout are shown. The dynamometer setup is used to measure the torque output on the turbine shaft. The tight side and slack side of the rope brake dynamometer arrangement are connected with a weight pan and load cell, respectively. The equivalent operating head of the turbine is calculated using the pressure difference created between the rotor’s upstream side and downstream side. The pressure is measured using a pressure gauge, as shown in Figure 8.
Advanced sensor-based maintenance in real-world exemplary cases
Published in Automatika, 2020
Michele Albano, Luis Lino Ferreira, Giovanni Di Orio, Pedro Maló, Godfried Webers, Erkki Jantunen, Iosu Gabilondo, Mikel Viguera, Gregor Papa
Measuring the pressure of pumps can reveal their physical changes. Operating conditions, such as fluid type, temperature, and speed affect the pressure, and if the pressure goes outside a given range, there is the possibility of damaging parts. Moreover, pressure variation can lead to cavitation (creation of vapour cavities in a fluid), which can potentially lead to material damage [35]. Cavitation can be sensed either by means of pressure or vibration or acoustic emission or sound measurement.
Optimal configuration and energy management for combined solar chimney, solid oxide electrolysis, and fuel cell: a case study in Iran
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2023
Xi Fei, Ruan Xuejun, Navid Razmjooy
Bernoulli’s principle is about how the speed of a fluid relates to the pressure of the fluid. This relation is reversed, i.e. with increasing the speed of the fluid, the pressure and the potential energy of the fluid will be decreased.