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Properties of Air and Compounds of Concern
Published in Jeff Kuo, Air Pollution Control Engineering for Environmental Engineers, 2018
where R is the universal gas constant. Commonly-used energy units are Joule (J), calorie, and British thermal unit (BTU). Joule is the unit of work/energy in the SI. It is the work done on an object when a force of one Newton acts on that object in the direction of its motion for a distance of one meter (= 1 N-m). One calorie is the energy needed to raise the temperature of 1 gram of water by 1 °C, while one Btu is the energy needed to raise the temperature of 1 pound of water by 1 °F at the temperature when water has its greatest density (~39 °F or ~ 4 °C). One Joule is about one quarter of one calorie and is about one thousandth of one Btu. Conversions among these common units are: 1 J = 1 N-m = 9.45 × 10−4 Btu1 Btu = 1,055 J1 J = 0.239 calorie (1 calorie = 4.184 J)
Fundamental Concepts
Published in Efstathios E. Michaelides, Energy, the Environment, and Sustainability, 2018
A novice in the subject of energy may be easily confused by the plethora of commonly used units, which have historically emerged from a variety of sources. The Système International (SI) is the most commonly used system of units in the world (the United States is one of the few exceptions of countries that have not formally adopted the system) and the joule (J) is the unit of energy in this system. The joule is defined as the work done when a constant force of 1 newton (1 N) moves its point of application by 1 meter (1 m). In electricity applications, 1 J is performed when a charge of 1 coulomb (1 C) moves through an electric potential difference of 1 volt (1 V). In the realm of energy studies, 1 coulomb volt is equivalent to 1 newton meter.
Voltage, Current, and Power
Published in Muhammad H. Rashid, Ahmad Hemami, Electricity and Electronics for Renewable Energy Technology, 2017
Voltage is the electric potential that causes electrons to move around a closed circuit. Volt is the unit of measure for voltage. Volt is defined as the value of the potential difference for which the energy of one coulomb of electric charge (i.e., the charge of 6.241 × 1018 electrons) is one joule. Joule is a unit for measuring energy. This official definition of volt may not be much help to understand how much 1 V is. A better understating is possible by considering that each small dry battery you use in your battery-operated devices is 1.5 V, the car battery is 12 V, and the electricity at home is around 115 V. Also, lightning during a thunder storm has millions of volts.
Boundary layer formations over a stretchable heated cylinder in a viscoelastic fluid with partial slip and viscous dissipation effects
Published in Numerical Heat Transfer, Part A: Applications, 2023
To investigate the consequences of varying magnetic field strength on the flow and resulting heat transfer, Figures 4a, b are included. Joule heating is the process by which the flow of an electric current through a conductor generates heat. It is a significant phenomenon because it can be used to generate heat for a variety of applications. It is obvious that vertical magnetic field sets up a drag that opposes momentum transport due to which velocity boundary layer declines, as demonstrated from the results of Figure 4a. Moreover, the contribution of Joule heating toward heat generation grows upon increasing the magnetic interaction parameter as can be noticed from last term of the energy equation Eq. (4). Eventually, thermal boundary layer becomes substantially broader whenever higher value of is invoked. Such observation is in compliance with the findings of other authors (see [39, 40] etc.).
Experimental study of the effects of quadrupole magnetic field and hydro-thermal parameters on bubble departure diameter and frequency in a vertical annulus
Published in Experimental Heat Transfer, 2022
Habil Jafari Zandabad, Leila Jahanshaloo, Habib Aminfar, Mousa Mohammadpourfard
The proper power supply is needed to create the required heat flux, due to the Joule heating method. Joule heating is the procedure by which the passage of an electric current through a conductor creates heat. The amount of this heat generated by electrical conductor is proportional to its resistance and the passing current as it is shown in the following equation:
Contributions of vehicle dynamics to the energy efficient operation of road and rail vehicles
Published in Vehicle System Dynamics, 2021
Jenny Jerrelind, Paul Allen, Patrick Gruber, Mats Berg, Lars Drugge
Aligned with published research works, this review will use energy and power as relevant measures for energy consumption, energy/power savings and energy efficiency. Energy is commonly measured in Joule (J) and watt-hour (Wh) and is the total quantity of work done without reference to the duration of the work. Power is the rate of consuming or producing energy and is measured in J/s or watt (W).