Fundamentals of Heat and Mass Transfer
7th Edition
ISBN: 9780470501979
Author: Frank P. Incropera, David P. DeWitt, Theodore L. Bergman, Adrienne S. Lavine
Publisher: Wiley, John & Sons, Incorporated
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Chapter 7, Problem 7.146P
To determine
The rate of evaporation from a single droplet.
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Chapter 7 Solutions
Fundamentals of Heat and Mass Transfer
Ch. 7 - Consider the following fluids at a film...Ch. 7 - Engine oil at 100C and a velocity of 0.1 m/s flows...Ch. 7 - Consider steady, parallel flow of atmospheric air...Ch. 7 - Consider a liquid metal (Pr1), with free stream...Ch. 7 - Consider the velocity boundary layer profile for...Ch. 7 - Consider a steady, turbulent boundary layer on and...Ch. 7 - Consider flow over a flat plate for which it is...Ch. 7 - A flat plate of width 1 m is maintained at a...Ch. 7 - An electric air heater consists of a horizontal...Ch. 7 - Consider atmospheric air at 25C and a velocity of...
Ch. 7 - Repeat Problem 7.11 for the case when the boundary...Ch. 7 - Consider water at 27°C in parallel flow over an...Ch. 7 - Explain under what conditions the total rate of...Ch. 7 - In fuel cell stacks, it is desirable to operate...Ch. 7 - The roof of a refrigerated truck compartment is of...Ch. 7 - The top surface of a heated compartment consists...Ch. 7 - Calculate the value of the average heat transfer...Ch. 7 - The proposed design for an anemometer to determine...Ch. 7 - Steel (AISI 1010) plates of thickness =6mm and...Ch. 7 - Consider a rectangular fin that is used to cool a...Ch. 7 - The Weather Channel reports that it is a hot,...Ch. 7 - In the production of sheet metals or plastics, it...Ch. 7 - An array of electronic chips is mounted within a...Ch. 7 - A steel strip emerges from the hot roll section of...Ch. 7 - In Problem 7.23. an anemometer design was...Ch. 7 - One hundred electrical components, each...Ch. 7 - The boundary layer associated with parallel flow...Ch. 7 - Forced air at 250C and 10 m/s is used to cool...Ch. 7 - Air at atmospheric pressure and a temperature of...Ch. 7 - Consider a thin, 50mm50mm fuel cell similar to...Ch. 7 - The cover plate of a flat-plate solar collector is...Ch. 7 - An array of 10 silicon chips, each of length...Ch. 7 - A square (10mm10mm) silicon chip is insulated on...Ch. 7 - A circular pipe of 25-mm outside diameter is...Ch. 7 - An L=1-m- long vertical copper tube of inner...Ch. 7 - A long, cylindrical, electrical heating element of...Ch. 7 - Consider the conditions of Problem 7.49, but now...Ch. 7 - Pin fins are to be specified for use in an...Ch. 7 - Prob. 7.52PCh. 7 - Prob. 7.53PCh. 7 - Hot water at 500C is routed from one building in...Ch. 7 - In a manufacturing process, long aluminum rods of...Ch. 7 - Prob. 7.58PCh. 7 - To determine air velocity changes, it is proposed...Ch. 7 - Determine the convection heat loss from both the...Ch. 7 - Prob. 7.63PCh. 7 - Prob. 7.64PCh. 7 - Prob. 7.67PCh. 7 - A thermocouple is inserted into a hot air duct to...Ch. 7 - Consider a sphere with a diameter of 20 mm and a...Ch. 7 - Prob. 7.76PCh. 7 - A spherical, underwater instrument pod used to...Ch. 7 - Worldwide. over a billion solder balls must be...Ch. 7 - Prob. 7.80PCh. 7 - Prob. 7.81PCh. 7 - Consider the plasma spray coating process of...Ch. 7 - Prob. 7.83PCh. 7 - Tissue engineering involves the development of...Ch. 7 - Consider temperature measurement in a gas stream...Ch. 7 - Prob. 7.89PCh. 7 - A preheater involves the use of condensing steam...Ch. 7 - Prob. 7.91PCh. 7 - A tube bank uses an aligned arrangement of...Ch. 7 - A tube bank uses an aligned arrangement of...Ch. 7 - Repeat Problem 7.94, but with NL=7,NT=10, and...Ch. 7 - Heating and cooling with miniature impinging jets...Ch. 7 - A circular transistor of 10-mm diameter is cooled...Ch. 7 - A long rectangular plate of AISI 304 stainless...Ch. 7 - A cryogenic probe is used to treat cancerous skin...Ch. 7 - Prob. 7.103PCh. 7 - Prob. 7.104PCh. 7 - Prob. 7.105PCh. 7 - Consider the packed bed of aluminum spheres...Ch. 7 - Prob. 7.108PCh. 7 - Prob. 7.109PCh. 7 - Prob. 7.111PCh. 7 - Packed beds of spherical panicles can be sintered...Ch. 7 - Prob. 7.114PCh. 7 - Prob. 7.116PCh. 7 - Prob. 7.117PCh. 7 - Prob. 7.118PCh. 7 - Prob. 7.119PCh. 7 - Prob. 7.120PCh. 7 - Dry air at 35°C and a velocity of 20 m/s flows...Ch. 7 - Prob. 7.123PCh. 7 - Benzene, a known carcinogen, has been spilled on...Ch. 7 - Prob. 7.125PCh. 7 - Prob. 7.126PCh. 7 - Condenser cooling water for a power plant is...Ch. 7 - Prob. 7.128PCh. 7 - In a paper-drying process, the paper moves on a...Ch. 7 - Prob. 7.131PCh. 7 - Prob. 7.132PCh. 7 - Prob. 7.133PCh. 7 - Prob. 7.134PCh. 7 - Prob. 7.136PCh. 7 - It has been suggested that heat transfer from a...Ch. 7 - Prob. 7.138PCh. 7 - Cylindrical dry-bulb and wet-bulb thermometers are...Ch. 7 - The thermal pollution problem is associated with...Ch. 7 - Cranberries are harvested by flooding the bogs in...Ch. 7 - A spherical drop of water, 0.5 mm in diameter, is...Ch. 7 - Prob. 7.143PCh. 7 - Prob. 7.144PCh. 7 - Prob. 7.145PCh. 7 - Prob. 7.146PCh. 7 - Prob. 7.147PCh. 7 - Consider an air-conditioning system composed of a...Ch. 7 - Prob. 7.149P
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- In a drying process, the moisture content of 35 kg of food will be reduced from 82% to 6%. The air used for drying enters the dryer at 80 ° C and exits at 70 ° C. 130 kg of saturated steam is used at 105 ° C to heat the air. The food enters the dryer at 25 ° C and exits at 60 ° C. Calculate the drying efficiency for an adiabatic operating dryer, as the ambient air temperature is 20 ° C. (Specific temperature of the food = 3.30 kj / kg ° C) A.) 17% B.) 12% C.) 33% D.) 30% E.) 25%arrow_forwardA room is to be maintained at a state of 20 celsius degree dry-bulb and 50 percent saturation by a plant handling 0.5 m^3/s of outside air at a state of 0 celsius degree. the air steam is heated to a temperature warm enough to offset a heat loss of 2.5kw and dry steam is then injected to maintain the humidity required in the room. calculate the supply air tempetaure and the heating and humidification loads ?arrow_forwardIf the air temperature at 18:00h is 8 C, and the air adjacent to the surface has a relative humidity of 70%, at what time will condensation occur if the evening cooling rate is 1 C/hour? Will the condensation be in the form of dew or frost?arrow_forward
- In a falling-film evaporator, Air at 40℃ and 50 kPa flows through a wetted-wall column with 100 mm diameter at a velocity of 5 m/s. What is the mass-transfer coefficient for the humidification of this stream by evaporation from the wet walls? If the air in this situation is 50 % saturated, and the saturation particle pressure of water vapour at 40℃ is 7375 Pa, what is the local evaporation flux in a unit of kg/m²s?arrow_forwardThe effective surface temperature of the coil is 5°C. The surface area of the coil is such as would give 4.6 TR with the given entering air state of 40 m3/min of a mixture of recirculated room air and outdoor air enters cooling coil at 27°C dry bulb temperature and 15°C wet bulb temperature.. Determine the conditions of the air leaving the coil and the by-pass factor.arrow_forwardAir at 25°C and atmospheric pressure flows with a velocity of 3 m/s inside a 10mm diameter tube of 1 m length. The inside surface of the tube contains a deposit of naphthalene. Determine the average mass transfer coefficient for the transfer of naphthalene from the pipe surface into the air.arrow_forward
- An air dryer is used to dry wet coal at a rate of 10,000 tons per day. Wet coal feed has 24 percent by mass of water when it enters and 4 percent when it exits. The hot air used to dry the wet coal is heated to 40°C for the dry bulb and 16°C for the wet bulb. At 30°C, the moist air exits the dryer with a relative humidity of 40%. Calculate the dry amount of air in m3/h at STP. (Use psychrometric chart)arrow_forwardA countercurrent tunnel dryer was used to dry the ape slices from an initial moisture content of 70% to 10% (wet basis). Hot air enters at 95 C with 1% RH, and exits at 60.0 C. If the product temperature at drying length is 20˚C and the specific heat of the product solids is 2.2 kJ / (kg ˚C), determine the rate of hot air required to dry the wet product at a rate of 240 kg / hour. determine the RH of the drying air outlet. a. drying air rate (ma) = kg / hr b. RH of dryer exhaust air = %arrow_forwardThermal energy generated by the electrical resistance of a 5-mm-diameter and 4-m- long bare cable is dissipated to the surrounding air at 80°C. The voltage drop and the electric current across the cable in steady operation are measured to be 18 V and 5 A, respectively. Disregarding radiation, estimate the surface temperature of the cable. Evaluate air properties at a film temperature of 100°C and 1 atm pressure.arrow_forward
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