Example 2B.2: A 15-cm by 15-cm circuit board is being cooled by air. It is dissipating 890 W/m² of heat to the air from its top surface. The air approaches the circuit board at 25 °C with a velocity of 6 m/s. Determine the surface temperature of the circuit board at the end of the board. Assume the flow to be turbulent at the leading edge of the board since the electronic components are expected to act as turbulators. For air properties evaluations assume a film temperature of 35 °C. Given: Circuit board geometry – length, L = 0.15 m, width, W = 0.15 m Convective heat flux to air, q'" = 890 W/m² Free-stream temp., T = 25 °C. Free-stream velocity, U» = 6 m/s %3D Assumption: Steady state. Only mode of heat transfer from the board is convection. Film temperature is T; = 35°C. Properties are considered constant and uniform. Flow is turbulent. Air is an ideal gas. Properties: Air properties at 35°C: k = 0.0265 W/m°C; v = 16.5×10-6 m²/s; Pr = 0.7 %3D

Example 2B.2: A 15-cm by 15-cm circuit board is being cooled by air. It is dissipating 890 W/m² of heat to the air from its top surface. The air approaches the circuit board at 25 °C with a velocity of 6 m/s. Determine the surface temperature of the circuit board at the end of the board. Assume the flow to be turbulent at the leading edge of the board since the electronic components are expected to act as turbulators. For air properties evaluations assume a film temperature of 35 °C. Given: Circuit board geometry – length, L = 0.15 m, width, W = 0.15 m Convective heat flux to air, q'" = 890 W/m² Free-stream temp., T = 25 °C. Free-stream velocity, U» = 6 m/s %3D Assumption: Steady state. Only mode of heat transfer from the board is convection. Film temperature is T; = 35°C. Properties are considered constant and uniform. Flow is turbulent. Air is an ideal gas. Properties: Air properties at 35°C: k = 0.0265 W/m°C; v = 16.5×10-6 m²/s; Pr = 0.7 %3D

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

See similar textbooks

Related questions

Q: Corection the following number k=.02625,Kinematic viscosity(fancy v)=16.55*10^-6m^2/s,Pr=.7…

Q: Part A The data below shows the laboratory data for a fluid obtained using a viscometer at 20°C and…

A: According to Newton's law of viscosity, the shear stress is the product of the absolute viscosity…

Q: The operating conditions found at two different points of a blade on a wind turbine are shown. These…

A: Given Dataϑk=1.33×10-5Re=?

Q: Let vector Ğ be given by Ğ = (2xz)į + (x²/2)j - (z²)k. Calculate the divergence of G.

Q: Crude oil of kinematic viscosity (7/100000) m2/s flows through a pipeline of internal diameter 304.8…

Q: I need handuwritten solution. Strictly don't use chatgpt.

Q: A well with 4 in. radius produces oil with a viscosity of0.3 cP, at a rate of 200 barrels/day, from…

A: Radius=4inchViscosity=0.3cPRate=200barrels/daythickness=15ft t(mins) 1 5 10 20 30 60 Pw(psi)…

Q: Determine the apparent viscosity at a shear rate of 69.75/s and 75.69/s for the non-newtonian fluids…

A: Given Shear rate γ.1=69.75/sγ.2=75.69/s To find Apparent viscosity

Concept explainers

Properties of Fluids

The term fluid represents a type of substance that can easily change its shape under any external pressure/force and can flow. Fluids can acquire any shape in which it is stored and can resist normal stresses but cannot resist shear stress in rest condition. Whenever external shear stress is applied to fluids, it starts to flow. The fluids may be liquid or gas. Example- water, air, etc.

Question

Corection the following number k=.02625,Kinematic viscosity(fancy v)=16.55*10^-6m^2/s,Pr=.7

Re(x=L)=54380

Nu(x)=170.1

h(x=L)=29.8

Ts(l)=54.9C

Find out the total convective heat transfer rate from
the board in Example 2B.2 (solve the bolded part)
Example 2B.2: A 15-cm by 15-cm circuit board is being cooled by air. It is dissipating 890 W/m² of
heat to the air from its top surface. The air approaches the circuit board at 25 °C with a velocity of
6 m/s. Determine the surface temperature of the circuit board at the end of the board. Assume the
flow to be turbulent at the leading edge of the board since the electronic components are expected to
act as turbulators. For air properties evaluations assume a film temperature of 35 °C.
Given: Circuit board geometry – length, L = 0.15 m, width, W = 0.15 m
Convective heat flux to air, q' = 890 W/m²
Free-stream temp., T = 25 °C. Free-stream velocity, U» = 6 m/s
Assumption: Steady state. Only mode of heat transfer from the board is convection. Film temperature
is T¡ = 35°C. Properties are considered constant and uniform. Flow is turbulent. Air is an ideal gas.
Properties: Air properties at 35°C: k = 0.0265 W/m°C; v = 16.5×10-6 m²/s; Pr = 0.7

Expert Solution

This question has been solved!

Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.

SEE SOLUTION Check out a sample Q&A here

Step 1

VIEW

Step 2

VIEW

Step by step

Solved in 2 steps with 2 images

SEE SOLUTION Check out a sample Q&A here

Knowledge Booster

Learn more about

Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.

Similar questions

i need the answer quickly
Can i get the answer as an image i cant see the hold write up Tried using my laptop same issue
n = Xe()r -------Equation 1 where X = 1.7419 and (E/R) = -0.018 are constants for a given fluid. You are required to carry out appropriate calculations on the effect of changes in temperature given in table A by using equation 1 for Ethanol on the viscosity of a fluid. Table A NO Temperature viscocity n T°C cP 10 3 20 30 5 40 6. 50 7 60 8 70 In addition to this, calculate other constraints such as the variety of shear stress (T) and force due to fluid viscosity, when the two layers of different compressible Newtonian fluids are contained between two flat plates separated by a distance of 0.05m and fluid moving with the velocity of 2m/s in the horizontal direction. Assume the shear area between the fluid layers is 0.5m². To do this you required to explain, with examples, the effects of temperature and shear forces on Newtonian and non-Newtonian fluid. Also, explain the operation and constraints of different viscometers that quantify viscosity in fluids. 2.
flow in a pipe questions e-g
% ParametersD = 0.1; % Diameter of the tube (m)L = 1.0; % Length of the tube bundle (m)N = 8; % Number of tubes in the bundleU = 1.0; % Inlet velocity (m/s)rho = 1.2; % Density of the fluid (kg/m^3)mu = 0.01; % Dynamic viscosity of the fluid (Pa.s) % Define the grid size and time stepdx = D/10; % Spatial step size (m)dy = L/10; % Spatial step size (m)dt = 0.01; % Time step size (s) % Calculate the number of grid points in each directionnx = ceil(D/dx) + 1;ny = ceil(L/dy) + 1; % Create the velocity matrixU_matrix = U * ones(nx, ny); % Perform the iterationsfor iter = 1:100 % Calculate the velocity gradients dUdx = (U_matrix(:, 2:end) - U_matrix(:, 1:end-1)) / dx; dUdy = (U_matrix(2:end, :) - U_matrix(1:end-1, :)) / dy; % Calculate the pressure gradients dpdx = -mu * dUdx; dpdy = -mu * dUdy; % Calculate the change in velocity dU = dt * (dpdx / rho); % Update the velocity matrix U_matrix(:, 2:end-1) = U_matrix(:, 2:end-1) + dU; % Apply…
Pls show proper steps with explanation.
f. A study of the physical characteristic of honey was conducted due to the large demand of royal jelly. A capillary tube viscometer was used by a researcher in determining the viscosity of the honey. The viscometer is 250 mm long with an outside diameter of 55mm and effective thickness of 2.5mm and was used horizontally so that the effect of gravity was neglected. At an ambient temperature of 30°C the following data were collected: Q (cc/s) 1.25 1.55 1.80 2.05 ДР (Ра) 10.0 12.5 15 17.5 20.0 2.55 What will be the stress produced per unit length in the tube used in the production of royal jelly if it has a radius of 5mm and a flow of 1 capsule per second. (1 capsule = 0.85 cc of royal jelly).
b
A cheap accelerometer, probably worth the price, can bemade from a U-tube as in Fig. . If L = 18 cm andD = 5 mm, what will h be if a x = 6 m/s 2 ? Can the scalemarkings on the tube be linear multiples of a x ?
Stop using Chatgpt. I need a correct handwritten solution.
Problem 6-1: The Reynolds number is an engineering parameter that relates to the volume flow rate of a fluid 4Q where vis πνd m² through a tube of diameter d as Red the fluid kinematic viscosity. Determine the Reynolds number and its uncertainty by general analysis given d = 50.4 ±0.1 mm, Q = 0.213 +0.005 S v = 0.999 × 10-6 ± 0.005 × 10-6 m². Which variable contributes the most to the overall uncertainty? Assume uncertainties are at 95 % confidence. S