Hi all,
I have a copper pipe which has 15mm of insulation on it. The outside radius of the pipe is 17.2mm and the inside radius is 14.8mm. The insulation will have a conductivity of 0.025.
I found an question which is meant to show an equation for the heat loss in an Insulated Cylinder or...
This is a past exam paper Q.
I think i might be missing info though.
For i) i use q=UAdT
A= 35m2
dT= (80-20)
They haven't given U but if i know answer should be 1,050W
So if i set U to 0.5
(0.5)(35)(60)
= 1050W
Am i missing something or could I calculate U with the info given?
Also ii)
Use...
Flow delivered by a pipe can be calculated from input pressure, inlet geometry, pipe length, and a flow coefficient related to pipe cross-section, shape, and roughness. If we create an example of a pipe attached at the bottom of a self-refilling standpipe, which automatically supplies a...
I do not know where I am doing wrong. I asked a tutor, he said I was doing it correctly.
Below is my work. Please help!
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Hi,
If it is assumed the temperature of a shower is to be 43°C and the electric shower consumes 50 litres of water at that temperature, then the Energy required for an electric shower would be:
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Summary: Pipe Testing
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Thank you for your help.
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(8.59)
from (8.58)
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Homework Statement
Calculate the insertion loss of the T-network given the values:
Rs = 75Ω
Rl = 100Ω
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Rb = 13Ω
Rc = 213Ω
The transmission matrix and Network are below:
2. Homework Equations
The Attempt at a Solution
Constructing the matrix:
A = 1+Ra/Rc = 1+13/213 = 1.061
B...
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Homework Statement
Homework EquationsThe Attempt at a Solution
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Homework Statement
Problem: An object with mass 2.0 kg slides down a low-friction incline and its speed measured at the bottom is 2.7 m/s. The object starts sliding at a height of 0.50 m over the tabletop and its speed is measured 0.10 m over the tabletop. How big is the percentage energy loss...
Homework Statement
Homework Equations
y1 + P1/##\gamma##+v1/2g=y2 + P2/##\gamma##+v2/2g+hL
The Attempt at a Solution
I used the above equation and assumed that P1=0 and both velocity heads are equal. Is that valid? However I did not need to use the geometry of the pipe so I think I am doing...
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Homework Statement
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Hi,
I'm trying to simulate the process of charged particles attenuation in matter (like this) by a montecarlo-metropolis algorithm in Python. I thought that I could use for the number of particles at thickness ##x## the formula ## N (x) = N_0 e^{-\mu x} ##, so the probability in this case will...
Hi everyone
I'm new around here and I wonder if anyone can help please. I'm taking hot air off the chimney stack inside a factory at a temperature ranging between 700 and 400 degrees going through a 4 inch stainless steel pipe with 3mm wall thickness. This pipe line will be about 35 meters long...
Hi all,
Quick question:
What do you guys use as your reference for minor head loss coefficients (k).
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Hi all,
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Homework Statement
Find the admissible current density Jadm for a wire that has no insulation and also for a wire that has two layers of insulation and compare it to Jadm for the case when the wire has only one layer of insulation.2. The attempt at a solution and equations
In the image I've...
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Homework Statement
why is there a loss of energy in DC circuits and power loss is reduced in AC when transmitted
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Homework Statement
similarities and differences of AC and DC current in simple circuits. Outline using diagrams and a clear desciption the loss of energy in DC circuits and power loss reduction of AC when transmitted.
Homework Equations
N/A
The Attempt at a Solution
DC loses energy over long...
Homework Statement
A careless farmer sends this sheep out to graze on a very cold winter day when the temperature is -10oC. The sheep's coat has a thickness of 4.7 cm and a surface area 1.3 m2.
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Hello all,
I want to know about turbo alternator real power producing capability under loss of excitation condition.
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Homework Statement
Is the following conclusion correct? Assume there's an equation with vectors on both sides. Taking the dot product of this equation with vectors on both sides loses information, but information will not lose when taking dot products with higher rank tensors on both sides...
<< Mentor Note -- poster reminded to use the standard Template >>
Question Three
A pipe of outside diameter 200 mm is lagged with an insulating material of thermal conductivity 0.06 W m-1 K-1 and thickness 75 mm. The pipe carries a process fluid at a temperature of 300 °C and the average...
Question - Four
A pipe carrying superheated steam at 300 °C has an outside diameter of 120 mm and is lagged with two layers of insulating material. The first layer (adjacent to the outer pipe wall) is 25 mm thick and has a thermal conductivity of 0.072 W m-1 K-1. The second layer (covering the...