Homework Statement
A single roomed building measureing 12.0m x 12.0m x 2.5m is maintained throughout the day at a temperature of between 18-23°C. Each wall is to be constructed from 2 layers of common brick, an internal particle board and a layer of insulation. The building is heated using...
Modern foil covered foam insulation and coated window glass unfortunately blocks mobile phone signals rather well. I'm aware of solutions that use broadband and wifi to tunnel through it but this seems like a problem waiting for a better solution.
Are there any good/cheap alternatives to...
Homework Statement
Doing my homework I came across the question:
why it would be better to have styrofoam on the inside of the house
And why it could be better to have it on the outsideThe answer is
The steady state will be the same for both but
inside: warm and cold quickly
Outside...
Homework Statement
Determine the insulation resistance in a coaxial cable of length L, with conductivity, as shown in Figure assume that the current density J is radial direction.
The Attempt at a Solution
so i was wondering if this approach is correct,
consider a sequence of...
During exploring the Electrical Transmission and Distribution Network I came across the following terms.
"Supply, installation, testing and commissioning of LV 600V/1000V insulation grade Panel Board consisting of following but not limited.
I). 2700A single bus bar.
II). 2x2700A Off...
Hi,
I'm doing a group investigation on external wall insulation for my school building. The walls do not have a cavity and thus it has been proposed to put insulation over the exterior render of the wall.
This is a fairly common building procedure.
However, my task is to investigate the...
Homework Statement
Determine the resistance of the insulation in a length l of coaxial cable.inner radius = a and outer radius= b.Homework Equations
R=\rho\frac{l}{A}
Area= \pi (b^2 - a^2)
The Attempt at a Solution
I calculated the area between the two concentric 'circle' with radius 'a'...
Howdy everyone, I'm sorry if this is in the wrong forum, but since I believe it is mostly a thermodynamics problem I think this is the right arena. My questions stems from trying to insulate a bank of batteries in cold weather. I am trying to determine the proper material and design...
Over about the last decade I have encountered with increasing frequency a black corrosion on the strands of copper wire.
When you strip the wire it'll be jet black instead of old copper brown.
It cannot be soldered.
It is a real nuisance when trying to repair something like an automobile...
Dear Seniors and Friends
We have a thermocouple consisting of two pipes . In the inner pipe there is the flue gas and the outer pipe we have a cooling water . Currently we are facing a problem that gases are being condensed below 100 C because of cooling water .We have to apply insulation...
Hi Seniors and Fellows
I really need your help to finish my project .I have struck at a point which is given below :-
I have to do insulation around a vacuum tube in which thermocouple is placed . I have to choose a high temperautre 650 C insulation material. Inner and outer diameter of...
I've always wondered this. I have blankets of different materials and thicknesses. In very cold nights I sometimes have to use three or four of them when sleeping. Traditionally I put the thinnest blankets (least insulating) ones first (close contact to body) and the best blanket last, because...
I'm going to be reviewing some insulated sheets for lining walls. I want to set up an experiment to rank different types of sheet by their level of insulation.
I intend to use a digital thermometer with a probe (for example...
Hello I have a very basic question.
I'm studying power cable engineering right now and I've learned about the role of insulation in a cable to reduce dielectric losses and charging current losses, but I don't understand what this means exactly. Here are my questions..
1. Is the insulation...
I'm trying to calculate insulation thickness for a foundry, and can't figure it out after spending a few hours searching.
Refractory: Kast-O-Lite
Material Required: 1.44g/cm^3
Thermal Conductivity: 0.65 W/m*C
Maximum inside temperature is 1648*C
I figured there would be a minimum of...
Strange title? Basically, a few days ago we got a dead rat in our ceiling, which is covered in insulation. Took a while to find it, but it got me thinking, how would you detect a dead rat body?
If it recently died, I first thought you could use thermal imaging (aside from the expensive aspect)...
Hi All,
I'm working on a Hydraulic Tire Curing Press Project.There are Hydraulic cylinders in many regions of the press.Steam @ 220 deg c is used to heat the tire to bring about vulcanization process.The press earlier supplied to the customer had thermal insulation problems due to which the...
Homework Statement
A wall is required to be insulated by embedding wood within concrete. the total thickness of the concrete and wood are 10cm and 1 cm respectively and are fixed due to structural constraints. determine the minimum heat leak into the room if the location of the wood can be...
Ice as pipe insulation?
OK so this is a problem me and some co-workers have been discussing. We have refrigeration pipelines that are about 15°F. It is very hot and humid here (assume about 90°F and 75% humidity) so condensation often forms on the pipes and freezes. Thinking of it as a pure...
I am hoping for some advice on materials to be used for insulating up to 70kV. I am doing some preliminary research for an application in the aviation industry, however I am not an engineer and need some guidance. I have looked at mica sheet, although to insulate against such high voltages it...
Hi
I am looking for some thin and light heat insulation materials probably in a flat plate form.
We intend to install this kind of heat insulation plate underground for separating different utilities.
Any suggestion ?
Thanks alot.
Hi
I am looking for some thin and light heat insulation materials probably in a flat plate form.
We intend to install this kind of heat insulation plate underground for separating different utilities.
Any suggestion ?
Thanks alot.
hi everyone...i want to know tht how we determine the amount of porcelain insulation to be done in any electrical systems situated in a substation? please help
Need a rigid insulation material?
I have a project that requires insulation sheets that are rigid and difficult to compress, about 1/8" thick. I was thinking about some type of ceramic material but can't find anything in that thickness. I'm not looking for some type of exotic material, just...
Hello.
I am currently investigating the relationship between the thickness of insulation and the temperature of the system being insulated. The material I used was card - not a common insulator, I know, but the variable in question was thickness. What I found was most interesting: for the first...
Ok guys I have a stator/alternator on one of my motors, and the thing finally gave out on me. You can tell where the wire got hot and burnt through the insulation. I have heard that you can use thinned down JB weld as a good insulator. How important is it that the insulation be the same...
Hello,
Suppose there are two conductors carrying currents. One of them is bare conductor and the other has insulation. Now magnetic field will be created around them due to the current flow through them. What will be the condition of magnetic field strength around them? They have same field...
hello everybody, I'm new here and i have this homework which i don't know how to solve it, please help me:
Design the thickness of insulation for steam pipe of:
-Pipe diameter 2 in.
-Pipe length 200 m.
-Saturated steam pressure 10 bar.
-Ambient temperature 30°C.
-Steam cost $4.5/MMbtu
i...
Alright, chemistry student here. No previous experience with these types of problems. Doing an interdisciplinary student project where we have to insulate a thin aluminum wall.
http://i.imgur.com/8ztNq.gif
We have a x=5mm thin aluminium wall used for dividing two air flows. T1=308 K and...
I wish to design highly insulating structural load-bearing walls using local materials. Part of that effort requires an understanding of the dynamics of current insulation materials and why some are much higher in R-value while using the same base material. Part of my study so far suggests that...
Hi,
Why do all the designs for a Van de graaff generator have a insulated belt that delivers charge?
Couldn't I just connect the negative terminal of a battery to the inside and get the same effect?
Van de graaf from wikipedia
http://en.wikipedia.org/wiki/File:Van_de_graaf_generator.svg
I would like to know if there is a formula or a way to determine the amount of insulation a vacuum of 1 bar can produce. please note I am not talking about vacuum insulated panels.
Hi,
I am trying to keep a small vial of liquid cold (> 2 Celcius but < 8 Celcius) for 10 hours when the ambient temperature is 20 -> 30 Celcius. So if I'm making a container to hold it I'd like to know what is the best material to use. My initial thought was to simply place it in a thermos...
I was having a discussion about thermal insulation (high temperature) and I thought that positive pressure (meaning the heat is being blown onto the insulation) would reduce how effective the insulation was.
Say a 1/2" of insulation reduced temperature from 1000 degrees F to 500 degrees F...
Hi, guys!
(I created the same thread in the Engineering topic nearly a week ago but there has been no response. So I decided to move it here. Thanks.)
A few friends and I just had a discussion regarding heat and cold protection in general. Then came across a question of whether it is more...
Hello Everyone.
As an engineering student, I've been reviewing this forum many years. This is my first question.
My team and I are designing a radiant floor heating system using pex tubing.
The inlet water to pex tubing is 180 F, we assume that the outlet temperature will have a delta T loss...
I was hoping there is somewhere on here that can help
Im working on a project designing a superconducting transformer
currently i have to report possible options to use. Does anyone have any experience with cryogenic insulation if so what can you recomend.
It looks like glass microspheres or...
Types of metals, plastics and others like fiber glass.
Also I have another question.
How do I calculate how long it takes to heat liquid up with different amounts of energy.
Say from -40c, how long does it take to heat oil to 71c with a 120volts. This is bare bones, but I just want to know...
A roof drain leads to a pipe that lies horizontaly in the roof's insulation layer which in turn lies on top of a 26cm concrete slab. On top is the waterproof membrane. The area underneath the roof is room temperature. The question is this; is it necessary to insulate the pipe itself to prevent...
Hello,
I have been reading this forum for quite some time now and I find it to be very helpful. Today, I am going to need the help from all of you generous people in the forum to assist me in the following question:
My colleagues and I designed a downdraft gasifier that is able to deliver...
Hi everybody,
Homework Statement
For one project, I need to find a material to control the heat transfer between two plates of aluminium by adding a plate or something in between. I'm so looking for a material which can help to reduce the heat transfer between the two plates (one about...
I have an assignment and don't even know where to start so that's y am asking the experts on here to give me an idea how to go about this:
In a company factory, a steam line has been identified as loosing too much heat. The steam line has a diameter of 254mm ( it may be considered to be thin...
hello,
i'm new here and this is my first question i hope you can help me all.
i live in germany that's why sorry for my english if i make gramma mistakes or other mistakes.
now to my question:
i wanted to know what kind of stuff can effect the insulation of clothes or of all types...
Hi
I am working at a manufacturing plant and we are applying a second layer of glass fibre/alumnium foil insulation to an industrial cylindrical boiler, on top of a previous layer. I need to calculate the approximate savings to be able to give a ROI figure.
The surface temp of the current...
Insulation as I know it, prevents heat transfer, and that's how a beverage cooler works to keep things cold right?
I was wondering if it worked the same way in the opposite situation: do coolers keep things from freezing under freezing conditions?
To be honest, I'm actually wondering if...
Homework Statement
This is a multi-part problem.
Visible light spans a range of wavelength between 0.4-0.7 nm, corresponding to a photon energy between about 1.8 and 3.1 eV.
(a) An old practical test says that if you can see through a piece of material, it is almost certainly a good...
Hi,
I was wondering if anyone here has any good suggestions for foam insulation for high altitude balloons. We're looking at temperatures as low as -60 deg. Any recommendations on supplier as well?