Heat transfer by natural convection

Assignment Help Mechanical Engineering
Reference no: EM13947630

A freezer compartment is covered with a 2-mm-thick layer of frost at the time it malfunctions. If the compartment is in ambient air at 20°C and a coefficient of = 2 W/m2 · K characterizes heat transfer by natural convection from the exposed surface of the layer, esti- mate the time required to completely melt the frost. The frost may be assumed to have a mass density of 700 kg/m3 and a latent heat of fusion of 334 kJ/kg.

Reference no: EM13947630

Questions Cloud

Calculate the before-tax and after-tax costs of debt : Cost of debt using both methods: Currently, Warren Industries can sell 15-year, $1,000-par-value bonds paying annual interest at a 12% coupon rate. As a result of current interest rates, the bonds can be sold for $1,010 each; flotation costs of $30 p..
How does maximum flange horizontal offset allowable : How does the maximum the 10 flange horizontal offset allowable
Instantaneous rate of melting during irradiation : Allowing for convection to  ambient  air,  with T00 = 20°C and h = 15 W/m2 · K, and radiation exchange with large surroundings (s = 0.4, Tsur = 20°C), determine the instantaneous rate of melting during irradiation.
Butterfly spread from options with strike prices : A trader creates a long butterfly spread from options with strike prices $60, $65, and $70 by trading a total of 400 options. The options are worth $11, $14, and $18. What is the maximum net gain (after the cost of the options is taken into account)?..
Heat transfer by natural convection : K characterizes heat transfer by natural convection from the exposed surface of the layer, esti- mate the time required to completely melt the frost. The frost may be assumed to have a mass density of 700 kg/m3 and a latent heat of fusion of 334 k..
Classifying liabilities and preparing payroll entries : The following items appear on the balance sheet of a company with a two-month operating cycle. Identify the proper classification of each item as follows: C if it is a current liability, L if it is a long-term liability or N if it is not a liabili..
Should henderson company make or buy the subassembly : Should Henderson Company make or buy the subassembly? If it makes the sub- assembly, which alternative should be chosen? Explain and provide supporting computations.
Following transactions that affected the common stock : On January 1, 20 x 1, Wilk Corp. had 480,000 shares of common stock outstanding. During 20 x 1, it had the following transactions that affected the common stock account.
Stocks market price can deviate from its intrinsic value : It has been argued that stock’s market price can deviate from its intrinsic value. If all investors attempt to behave in an entirely rational manner, could these differences still exist? the fact that historical probabilities of financial events are ..

Reviews

Write a Review

Mechanical Engineering Questions & Answers

  A power plant based on the rankine cycle is under

a power plant based on the rankine cycle is under development to provide a net power output of 10 mw. solar collectors

  The mass of the pellet is 200 grains determine the maximum

when the rubber bands of the sling shot are pulled back each rubber band is stretched 3 in. the natural length and the

  What is the rate of work if isentropic efficiency

A turbine receives 10 kg/s of steam at a state of p1 = 5 bar, t1 = 400?c and exhausts to a pressure of p2 = 1.5 bar. The ambient temperature is t0 = 300c and the ambient pressure is p0 = 1 bar. What is the rate of work if isentropic efficiency is 75%..

  Determine the power generated by the motor m

Determine the power generated by the motor M at this instant if it operates with an efficiency of epsilon = 0.8.

  Simple steam power plant with a mass flow rate

The steady state operation for a simple steam power plant with a mass flow rate of 1 kg/s is shown in the figure. Determine 1) the thermal efficiency of the process and 2) mass flow rate of cooling water in kg/s (assume condenser is well insulated)

  Specify crucial resources that you need as a project manager

Specify the crucial resources that you would need as a project manager to run the existing business interests at the same time that the business changes to the production of touring class motorcycles.

  What is the actual strain

You have a 120 Ω quarter bridge 2 wire set up with Sg=2.10 and an unknown lead wire resistance. A 59880Ω calibration resistor is switched in parallel to the gage only and a recording instrument is set to give a -100 mm deflection for this calibrat..

  Stray heat transfer and kinetic and potential energy

water vapor at 6 mpa 600degc enters a turbine operating at steady state and expands to 10 kpa. the mass flow rate is 2

  The gap width is g mm and the inner cylinder radius is r mm

a fluid has a viscosity of x nsm2 and is placed in a concentric cylinder viscometer. the gap width is g mm and the

  In a hydroelectric power plant water enters the turbine

in a hydroelectric power plant water enters the turbine nozzles at 880 kpa absolute with a negligible velocity. if the

  Determine the moisture composition of the drying medium

A small droplet of liquid detergent, falling through air in a spray drying tower, has its diameter reduced as water evaporates from the surface. If we assume that the temperature of the liquid within the drop remains at 290 K and the dry air is at..

  Expression for the average convection coefficient

Develop an expression for the average convection coefficient, hturb(x), as a function of distance from the leading edge, x, for the turbulent region, xc x L.

Free Assignment Quote

Assured A++ Grade

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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd