Q1. (Reading: Çengel and Boles, Thermodynamics: An Engineering Approach, 8th Ed., Pages307-311) The amount of energy waste by a refrigerator increases by a number of malpractices.For example; opening the refrigerator door frequently will increase energy waste as the warmerair outside replaces the cool air inside. It is also not recommended to place the hot foods intothe refrigerator before cooling them to the room temperature.Imagine a typical household refrigerator with an internal temperature of 4 °C. The refrigeratorhas a coefficient of performance of 1.4. The internal dimensions of this refrigerator are 186 cm(height) x 84 cm (width) x 75 cm (depth). The half of the refrigerator volume is used for storingfood items. The air filling the other half of the refrigator volume contains 0.004 kg moisture/kgair on average. While the moisture content of the air in the kitchen is 0.01 kg/kg air, thetemperature and pressure in the kitchen are 23°C and 97 kPa, respectively. Assuming that thecost of electricity is 0,4 TL/kWh, determine the followings:а.Consider that a cooking pan containing food with an average temperature of 95°Cis placed into the refrigerator everyday. The average mass and specific heat of the pan with thefood inside is 5 kg and 3.9 kJ/kg °C. Calculate the amount of saving in a year if theinto the refrigerator after cooling to room temperature.panisputb.What is the annual cost of energy waste arising from opening the refrigerator doorif the door is opened 10 times everyday? Assume that at each opening of the refrigerator, all ofthe cold air in the refrigerator is replaced by the air in the kitchen.

Refrigeration: Refrigeration is the process in which heat is extracted from the body or space whose…

a. Consider that a cooking pan containing food with an average temperature of 95°C is placed into the refrigerator everyday. The average mass and specific heat of the pan with the food inside is 5 kg and 3.9 kJ/kg °C. Calculate the amount of saving in a year if the pan is put into the refrigerator after cooling to room temperature. b. if the door is opened 10 times everyday? Assume that at each opening of the refrigerator, all of What is the annual cost of energy waste arising from opening the refrigerator door the cold air in the refrigerator is replaced by the air in the kitchen.

a. Consider that a cooking pan containing food with an average temperature of 95°C is placed into the refrigerator everyday. The average mass and specific heat of the pan with the food inside is 5 kg and 3.9 kJ/kg °C. Calculate the amount of saving in a year if the pan is put into the refrigerator after cooling to room temperature. b. if the door is opened 10 times everyday? Assume that at each opening of the refrigerator, all of What is the annual cost of energy waste arising from opening the refrigerator door the cold air in the refrigerator is replaced by the air in the kitchen.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.19P

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