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Vehicular And Marine Lighting
Published in Randall Noon, Introduction to Forensic Engineering, 2020
One of tungsten’s attributes, with respect to light filaments, is that it has the highest melting point of all the metals - 6,170 degrees Fahrenheit. It is electrically conductive and can be drawn into a fine wire. This combination of characteristics makes it an excellent material for incandescent light filaments. In an incandescent light bulb, electric current passes through the filament and causes it to heat up enough to emit visible light. Unlike most metals, tungsten has melting point higher than the temperatures at which incandescence occurs, which varies between 4,000 and 5,500 degrees Fahrenheit.
Questions
Published in Michael de Podesta, Understanding the Properties of Matter, 2020
An incandescent light bulb is essentially a heater: a small section of wire – the filament – is heated until its temperature is sufficient to cause it to glow. You might be surprised at how hot the filament becomes: in most light bulbs the temperature is around 1700 °C! Such extreme temperatures are required because the hotter the filament, the ‘whiter’ the light. However this requirement severely restricts the materials that can be used for a filament. Most commonly, the element tungsten is used. Let us try to work out how to design a filament for a 60 watt light bulb to operate from a 220 V supply. This is the kind of light bulb you might be using in a desk lamp as you read this. It might not seem to be much of challenge to ‘design a piece of wire’ but as you will see, working out the length L and diameter d of the wire is more complicated than it seems.
Downstairs
Published in Michael Allaby, Conservation at Home, 2019
An incandescent light bulb works by passing an electrical current through a filament, which heats the filament up until it glows. The bulb becomes hot, so much of the energy is wasted as heat. A fluorescent strip light generates no heat, making it cheaper to operate. This suggests that the bulb is inefficient, but all may not be as it seems. When you need the light on the temperature is often low — because it is dark outside, or a very dull day — so the additional warmth may not be wasted after all. If you used strip lighting instead would you need to turn the heating up just a little?
Application of a Standard Power Meter for Detection Source of Harmonic Pollution and Reducing Economic Losses at Power Grid
Published in Electric Power Components and Systems, 2020
Miona V. Andrejević Stošović, Dejan S. Stevanović, Predrag M. Petković
The following ten cases of different load types were considered: Incandescent light bulb (ILB)Fluorescent lamp (FL)Phillips Compact Fluorescent Lamp (PCFL)EcoBulb Compact Fluorescent Lamp (ECFL)6-pulse switched-mode power supply (SMPS)Adjustable speed drive (ASD)Six-Pulse HVDC (HVDC)6-pulse PWM controlled variable speed drive (PWM VSD)6-pulse 3-phase diode rectifier dc power supply (3-DR)Delta connected Thyristor Controlled Reactor (DTCR)
Cattaneo–Christov heat flux on MHD flow of hybrid nanofluid across stretched cylinder with radiations and Joule heating effects
Published in Waves in Random and Complex Media, 2022
Aamir Ali, Rukhsana Khatoon, Muhammad Ashraf, Muhammad Awais
Heat transfer is a subfield of thermal engineering that deals with the use, conversion, generation, and exchange of thermal energy between systems. There are several heat transfer mechanisms, including radiation, convection, and conduction. Heat transfer has numerous applications in climate engineering, chemical process industries, architecture, greenhouse effect, and human body heat transfer. Temperature gradients have a large influence on fluid properties. Temperature and viscosity, in particular, have a direct relationship in gases, whereas temperature and viscosity have an inverse relationship in liquids. Radiation is a method or mode of transferring energy from one medium to another without the use of a third medium. Radiation from radioactive elements is emitted in all directions and travels to the point of absorption. Radiation can take the form of waves or particles. Heat is particularly transferred in vacuum through radiation in the form of electromagnetic waves because these waves can be transferred without the use of any medium, namely space. Rehman and Shatanawi [45] studied the flow of Jeffrey fluid over an inclined surface with nonlinear thermal radiation, MHD, and heat flux effects. They use the shooting method to solve the problem numerically. Rehman et al. [46] presented a numerical comparison of stagnation point flow with the influence of chemical reaction, thermal radiations, stagnation point, and heat flux on the flow of Jeffrey fluid over an inclined stretched surface. Similarly, Rehman et al. [47] presented the effects of these properties for viscous fluid over a linear twisting cylinder. They present the numerical solution using the BVP-Midrch routine, which is included with the Maple software. The heat produced by the flow of an electric current through a conductor is referred to as Joule heating. Joule heating is used in a variety of everyday applications, such as electrical fuses, glowing filament of an incandescent light bulb, electrical tabletop hotplates, and so on. The effects of convection, radiation, and Joule heating for Newtonian and non-Newtonian fluid across a stretched cylinder have been studied by researchers [48–59]. Velocity slip effects, thermal radiation, and temperature convective boundary conditions will all be considered. Imtiaz et al. [60] investigated convective heat mass transport in a mixed convection flow with nanoparticles in the boundary layer. They discovered that as the Hartman number rises, so does the flow of fluid. Sayed et al. [61] investigated the peristaltic process for two separate nanofluid particles in a non-Newtonian fluid with convective boundary conditions along an inclined channel. They conclude that copper and aluminum oxide nanoparticles had a substantial impact on heat transfer coefficients and the axial velocity field.