Consider a person who is trying to keep cool on a hot summer day by turning a fan on and exposing his entire body to air flow. The air temperature is 85°F and the fan is blowing air at a velocity of 6 ft/s. If the person is doing light work and generating sensible heat at a rate of 300 Btu/h, determine the average temperature of the outer surface (skin or clothing) of the person. The average human body can be treated as a 1-ft-diameter cylinder with an exposed surface area of 18 ft2. Disregard any heat transfer by radiation. What would your answer be if the air velocity were doubled? Evaluate the air properties at 100°F.

Q: How does transient heat transfer differ from steady heat transfer? How does one-dimensional heat…

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Q: An average man has abody surface area of 1.8m2 and a skin temperature of 33degrees celcius .The…

A: The data given is, Surface area of the body, As = 1.8 m2 Skin temperature of the body, Tskin = 33℃…

Q: The vertical 0.8-m-high, 2-m-wide double-pane window consists of two sheets of glass separated by a…

A: The properties of air are given as – Calculating Grashof’s number

Q: c) Water is to be heated from 10°C to 80°C as it flows through a 2-cm-internal-diameter, 7-m- long…

A: here 2 question are there, both are not interlinked and as per honor code and answering guidelines…

Q: Show that the volume expansion coefficient of an ideal gas is B=1/T, where T is the absolute…

A: Assumption Pressure is constant ( P = C )   We know that change in volume due to thermal expansion…

Q: A long 10-cm-diameter steam pipe whose external surface temperature is 110°C passes through some…

A: In order to proceed with the problems some assumptions need to be considered. Steady operating…

Q: air at a dry ball temperature of 80 degrees C and 4% RH is passed over the cooling coil so that the…

A: Condition of air at state 1, =80oC and 4% RH Temperature of air after cooling,=35oC

Q: What are the best possible solutions to increase the heat transfer rate of a body?

A: There are three modes of heat transfer; Conduction, convection and radiation. For these all modes we…

Q: 4. A car engine with the dimensions 0.6 m high, 0.50 m-wide, and 0.8-m- long. The bottom surface of…

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Q: A Gasoline engine operating on an air standard condition has a clearance volume of 15cm3  and a…

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Q: What is a semi-infinite medium? Give examples of solid bodies that can be treated as semi-infinite…

A: A semi-infinite solid : It is idealized body that has single plane surface & extends to infinity…

Q: What is a fluid? How does it differ from a solid? How does a gas differ from a liquid?

A: The fluid is a substance that tends to flow. The liquid and gases are two types of fluids. The solid…

Q: QUESTION 7 As in the previous question, steam is flowing inside a 10-cm-diameter, long pipe whose…

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Q: The net radiant-heat exchange between a 20-by-20 ft rough plaster panel-heated ceiling and a…

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Q: Consider a sphere and a cylinder of equal volume made of copper. Both the cylinder and sphere 'are…

A: The answer is in next step

Q: b) A 0.4-W cylindrical electronic component shown in Figure Q3b with diameter 0.3 cm and length 1.8…

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Q: The components of an electronic system are located in a 1.5-m-long horizontal duct whose cross…

A: given data Length of the pipe L = 1.5m Cross section area of the duct = 0.2*0.2 m2  Temperature of…

Q: = Consider a person standing in a room at 23°C. Determine the total rate of heat transfer from this…

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Q: The components of an electronic system dissipating 180 W are located in a 4-ft-long horizontal duct…

A: The data given is Temperature inlet, Tin = 85°F Temperature inlet, Tout = 100°F  Area of cross…

Q: Consider a person standing in a room at 25°C. Determine the total rate of heat transfer and the heat…

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Q: Consider a person walking first in air and then in water at the same speed. For which motion will…

A: Calculate the Reynold number when person walking in air: Reair = VD/νair…… (1) Here, V is the…

Q: Iron with a power rating of 1200 watts is left on the ironing board. The convective heat transfer…

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Q: Consider a cold aluminum canned drink that is initially at a uniform temperature of 4°C. The can is…

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Q: Portable electric heaters are commonly used to heat small rooms. Explain the energy transformation…

A: Given:1st Law of thermodynamics: According to this law, total energy of the system is conserved,It…

Q: Consider a person standing in a room at 23°C. Determine the total rate of heat transfer from this…

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Q: Water is to be heated from 10°C to 80°C as it flows through a 2-cm-internal-diameter, 7-m-long tube.…

A: Given:Ti=10°C =283 KTe=80°C =353 KVolume flow rate,V=8 L/minV=8*10-360 =1.33*10-4 m3/sd=2 cm =0.02…

Q: The local atmospheric pressure in Denver, Colorado (elevation 1610 m), is 83.4 kPa. Air at this…

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Q: Consider hotdog being cooked in boiling water in a pan. Would the heat transfer be modeled as…

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Q: person extends his uncovered arms into the windy air outside at 54°F and 30 mph in order to feel…

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Q: A Gasoline engine operating on an air standard condition has a clearance volume of 15cm^3 and a…

A: Given data Clearance volume = 15 cm³ Displacement volume = 100 cm³

Q: Water is being heated in a closed pan on top of a range while being stirred by a paddle wheel.…

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Q: what are the different modes of heat transfer? Explain transfer of heat by convection process?

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Q: The components of an electronic system are located in a 1.8-m-long horizontal duct whose cross…

A: Given:- Ts=65 T∞=30 k=0.02717W/m.k v=1.744*10-5m2/s Pr=0.72345 V=200m/min D=20cm To Find:- The total…

Q: Q1: What is the difference between the forced convection and natural convection?

A: Both natural and forced convection are mode of heat tranfer in which motion of fluid takes place but…

Q: 7-34 An array of power transistors, dissipating 5 W of power each, are to be cooled by mounting them…

A: Determine the average film temperature by using the information given in the question. Here, Ts is…

Q: Air flows over a flat plate at a constant velocity of 20 m/s and ambient conditions of 20 kPa and…

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Q: An array of power transistors, dissipating 6 W ofpower each, are to be cooled by mounting them on a…

A: Given: The power dissipating by a single transistors, Q = 6 W The area of the square aluminum plate,…

Q: An average man has a body surface area of 1.8 m2  and a skin temperature of 330C. The convective…

A: Let A = Surface area of man body =1.8m2 V =1.2m/s h =Heat Transfer Coefficient =8.6XVX0.53 h…

Q: Consider turbulent forced convection in a circular tube. Will the heat flux be higher near the inlet…

A: When a fluid is forced through a plane surface or a tube by means of external force such as fan is…

Mechanisms of heat transfer

Heat transfer is an essential discipline in thermal engineering that deals with the transfer, conversion, usability, and creation of heat or thermal energy. Transfer of heat occurs through various mechanisms like conduction, convection, radiation, and change of phases. All these mechanisms have distinct characteristics, but these mechanisms can simultaneously occur in an identical system.