Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Consider the chip cooling scheme of Problem 3.146, but with an insulated top wall placed at the pin tips to force airflow across the pin array. Air enters the array at 20°C and with a velocity V that may be varied but can- not exceed 10 m/s due to pressure drop considerations. The pin fin geometry, which includes the number of pins in the N X N square array, as well as the pin diam- eter Dp and length Lp, may also be varied, subject to the constraint that the product NDp not exceed 9 mm. Neglecting heat transfer through the board, assess the effect of changes in air velocity, and hence ho, as well as pin fin geometry, on the air outlet temperature and the chip heat rate, if the remaining conditions of Prob- lems 3.146 and 3.27, including a maximum allowable chip temperature of 75°C, remain in effect. Recom- mend design and operating conditions for which chip cooling is enhanced. Hint: The air outlet temperature is governed by a relation of the form [(Ts - To)/(Ts - Ti)] = exp[-(h AtYo)/mcp], where m is the mass flow rate of air passing through the array, At is the total heat transfer surface area (chip and pins), and Yo is the overall surface efficiency defined by Equation 3.107.
Determine the temperature at which the diffusivity D of Cu in Al is twice the diffusivity at 500K. Using your result for D of Cu in Al at 500K, estimate the distance that a Cu impurity would diffuse in Al at 500 K after 1 hour. Use the simple estimat..
air at 100 kpa and 27degc enters an isentropic compressor at a rate of 100 ls and leaves at 1000 kpa. determine the
a gasoline delivery truck traveling at 80 kmhr decelerates at a constant rate to a complete stop 10 seconds. the
a 2 l bottle of a carbonated beverage coke at 20 degc is placed in a cooler with 10 l of saturated liquid water and 30
a rigid 2-ft3 vessel contains water originally at 150of and 5.07 percent quality. the water is then heated until its
the speed limit on a country road is 70 kmhr. the radius of curvature for a bridge on the road is 50 meters. a corvette
The mixing process is adiabatic and the mixture is expanded to a condenser pressure of 0.10 bar in a low pressure turbine of 78% internal efficiency. Determine the power output and the thermal efficiency of the plant.
a curve of radius 200m on a level road is banked correctly for a speed of 65 kmh. if an automobile of mass 2 mg rounds
a bicyclist of mass 70kg supplies 300 watts of power while riding into a 3ms headwind. the frontal area of the
a punching machine is driven by a motor which exerts a constant torque on the flywheel at a mean speed of 2 revs. if
two humid airstreams are adiabatically mixed at 1atm pressure to form a third stream. the first stream has a
a thin flat plate is installed in a water tunnel as a splitter. the plate is 0.3 m long and 1 m wide. the freestream
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +1-415-670-9521
Phone: +1-415-670-9521
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd