Answer:
we use
Circular copper rods of diameter D=1mm and length L=25mm areused to enhance heat transfer from a surface that is maintained atTs
,1=100 deg.C. One end of the rod is attached tothis surface (at x=o), hile the other end (at x=25mm) is joined toa second surface that is maintained at Ts,2=0deg.C. Air flowing between the surfaces (and over the rods)is also at a temperature T?= 0 deg. C, and has a convectioncoefficient of h=100 w/m2kelvin.
a. What is the rate of heat transfer by convection from a singlecopper rod to air?
b. What is the total rate of heat transfer from a 1 m x 1 m section of the surface at 100 deg.C, if a bundle of the rods is installed on 4-mm centers?
a. What is the rate of heat transfer by convection from a singlecopper rod to air?
b. What is the total rate of heat transfer from a 1 m x 1 m section of the surface at 100 deg.C, if a bundle of the rods is installed on 4-mm centers?
1 answer:
You might be interested in
Answer:
The spring is solid safe since calculated Ns > given Ns
Explanation:
Given data :
Wire diameter (∝)= 0.148 in
outside coil diameter(OD) = 2.12 in
free length (lo) = 2.5 in
Total coil ( Nt ) = 5.75
material = A227 Hard-drawn steel
attached below is the remaining part of the detailed solution
From Table
A = 140 kpsi.i, m = 0.190
Sut = A /
since given Ns = 1.2 < 1.36 (calculated Ns) hence the spring is solid safe
Answer:
Yes, the flow is turbulent.
Explanation:
Reynolds number gives the nature of flow. If he Reynolds number is less than 2000 then the flow is laminar else turbulent.
Given:
Diameter of pipe is 10mm.
Velocity of the pipe is 1m/s.
Temperature of water is 200°C.
The kinematic viscosity at temperature 200°C is m2/s.
Calculation:
Step1
Expression for Reynolds number is given as follows:
Here, v is velocity, is kinematic viscosity, d is diameter and Re is Reynolds number.
Substitute the values in the above equation as follows:
Re=64226.07579
Thus, the Reynolds number is 64226.07579. This is greater than 2000.
Hence, the given flow is turbulent flow.
Answer:
We are getting the outer surface temperature as To=54.415°Cwhich is greater than 50°C. Thus, its not safe as it causes thermal burns.
Explanation:
The solution and complete explanation for the above question and mentioned conditions is given below in the attached document.i hope my explanation will help you in understanding this particular question.
