# What is Air gap: Definition and 16 Discussions

An air gap, air wall, air gapping or disconnected network is a network security measure employed on one or more computers to ensure that a secure computer network is physically isolated from unsecured networks, such as the public Internet or an unsecured local area network. It means a computer or network has no network interfaces connected to other networks, with a physical or conceptual air gap, analogous to the air gap used in plumbing to maintain water quality.

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1. ### I Magnetic Field Intensity At the Inductor's Air Gap (+Fringing Flux)

Hi there! Sorry for the unclear images in the previous post. This time I upload pdf files for my derivation and the reference paper. So, when I design a switching power supply, usually I make an air gap at the transformer's core. This will alter the BH curve, preventing the core saturation...
2. ### Toroid with Air Gap magnetostatics problem

Homework Statement consider a toroidal electromagnet with an iron ring threaded through the turns of wire. The ring is not complete and has a narrow parallel-sided air gap of thickness d. The iron has a constant magnetization of magnitude M in the azimuthal direction. Use Ampere's law in terms...
3. ### Air resistance: cylindrical rotor in stator with air gap

Hello, I am currently doing research on the aerodynamic properties of a rotating cylinder in a cylindrical housing. The cylinder represents a rotor in a electric motor. The air gap between rotor and stator is about 0.5mm. I'm looking for a theoretical analysis and calculation on the...
4. ### Heat Transfer through multiple walls

Hi guys, I am newbie on thread and currently working on a project I need some help on the Heat flow on multiple walls. Here is the setup (see figure below) The first wall is a Steel material which has a 350C temperature(1kwatts) and the an Air Gap is present then followed by a Plastic wall...
5. E

### MMF/Flux density across air gap for a salient pole

Hi I am trying to understand the figure 2 I have attached to this post. From text: Ok, I get that the air-gap flux density varies in a sinusoidal manner, because the air gap length is not constant i.e. non-constant reluctance and hence non-constant magnetic flux density. What I do not...
6. ### Flux and Current of Magnetic Core With Air Gap

I am a student of electrical engineering. This task appears in our textbook. However, there were no solutions provided. I tried understanding the task but got lost in the process. This is why I seek help here on this site. I would like to ask you for guidance and any sort of advice on how to...
7. ### Determine flux in air gap (Magnetic Core)

1. Homework Statement As shown above Homework Equations *Not too sure if they are relevant. Pretty sure there's more. We have textbooks from the library as references but we still can't quite figure it out :/ Φ = BcAc = BgAg B = Φ/Ac = (Ni/R)/Ac R = lc/(Ac.μ) The Attempt at a Solution...
8. ### What's about no air-gap in motors?

Hi, I saw few threads here about air-gap in motors, and I wonder what if we ignore mechanical issues and make an "iron-gap" in the motor. for example: in linear motor(e.g. this cute one: https://www.physicsforums.com/threads/linear-motor-equations.794499/) if we make the tube between the stator...
9. ### Calculating flux density in an air gap

I am trying to calculate the flux density of an air gap in an electromagnet. I am following this page that calculates the flux density in a C core with an air gap. My confusion is that I am using 50Hz AC instead of DC I have control over the voltage amplitude since I would be using a variac to...
10. ### Electrical reason for big air gap of induction motor

in induction motor there is air gap between stator and rotor. the air gap needs to be as small as possible. but some air gap is needed for mechancial reasons. i understand that a big air gap would reduce power factor as you'd need more magnetizing current. but are there any advantages of big...
11. ### Calculating the B field in a small gap in a toroid

Homework Statement Take a steel core (K_m = 2500) electromagnet, bend it into a loop with a small air gap, and determine the B field in the gap. The cross-sectional area of the toroid is 4cm^2, and the air gap is 2.5mm. The current through the coil's 120 turns is 15 amps. The radius of the...
12. ### Purpose of Air Gap in Gas Lasers

What's the purpose of having an air gap in certain gas lasers? Just to be clear, I'm talking about the air filled space between the lasing gas (with glass separating the two), and the partially silvered mirror at the end that let's the light out. Why isn't the partially silvered mirror just at...
13. ### Air gap flux density in DC machine

Why is it that the air gap flux density is flat topped at no load. What happens to it's shape when machine is loaded?
14. ### Toroid Air Gap: MMF, B-H Curve, Flux Density & More

Homework Statement (I have done parts i) through v) correctly. It is the remaining two I'm stuck on. A toroid of rectangular cross-section has a height of 10mm, an inner diameter of 68mm and an outer diameter of 82mm. It is made of iron and is wound with 118 closely-spaced turns. When a...
15. ### Magnetic field through ferrous material and across air gap

I am attempting to determine how strong a magnetic field will be on the other side of a thick material and then across an air gap. For instance, I have a closed steel cylinder with a steel piston inside it. I plan to affix a permanent magnet to one side of the piston (inside the cylinder)...
16. ### Lorentz Force in Magnetic Circuit Air Gap

http://en.wikipedia.org/wiki/File:Magnetischer_Kreis.svg The attached image shows a magnetic circuit with a small air gap. The magnetic material on each side of the gap is attracted to the other side. I've seen the magnitude of the force calculated based on principle of virtual work...