Fundamentals of Momentum, Heat, and Mass Transfer 7th. Edition by James Welty, Gregory L. Rorrer, David G. Foster | 9781119723547 | 111972354X

Heat Transfer

Fundamentals of Momentum, Heat, and Mass Transfer

2 SOLVED PROBLEMS

106 SOLVED PROBLEMS

Question: 1.1

A jet aircraft is flying at an altitude of 15,500 m, where the air temperature is 239 K. Determine whether compressibility effects are significant at airspeeds of (a) 220 km/h and (b) 650 km/h. ...

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The test for compressibility effects requires calc...

Question: 2.3

A fuel tank is shown in Figure 2.3. If the tank is given a uniform acceleration to the right, what will be the pressure at point B? ...

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From equation (2-3)

\boldsymbol{\nabla} P=\...

Question: 30.2

In a humidification apparatus, liquid water flows in a thin film down the outside of a vertical, circular cylinder. Dry air at 310 K and 1.013 × 10^5 Pa (1.0 atm) flows at right angles to the 0.076-m-diameter, 1.22-m-long vertically aligned cylinder at a velocity of 4.6 m/s. The liquid film ...

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The liquid film on the outside of the cylinder rep...

Question: 24.3

A new gas separation process is being developed to separate ethylene (C2H4) from a gas mixture that contains ethylene, small amounts of carbon dioxide (CO2), and carbon monoxide (CO). As part of the process analysis, the gas-phase diffusion coefficient of CO2 gas in ethylene and the gas-phase ...

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For the

\mathrm{CO_{2}- e t h y l e n e}[/l...

Question: 31.6

A packed tower is used to reduce the ammonia (NH3) concentration in a gas stream from 4.0 to 0.30 mole%. Pure liquid water is fed to the top of the tower at a rate of 0.231 kg/s, and the gas is fed countercurrently to the bottom of the tower at a volumetric rate of 0.20 m³/s. The tower is packed ...

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The Flooding correlation will be used to estimate ...

Question: 30.6

The “bubbleless” shell-and-tube membrane aeration system shown in Figure 30.13 is used to transfer oxygen gas (O2) to liquid water. Water containing no dissolved oxygen is added to the tube side at the entrance at a bulk velocity of 50 cm/s. The inner diameter of the tube is 1.0 cm, and the tube ...

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The process analysis and solution strategy will re...

Question: 30.5

A holding pond containing a suspension of aerobic microorganisms is used to biologically degrade dissolved organic materials in wastewater, as shown in Figure 30.12. The pond is 15.0 m in diameter and 3.0 m deep. At present, there is no inflow or outflow of wastewater. The process uses an array of ...

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At the process temperature of 25 C, the Henry’s la...

Question: 30.4

One step in the manufacture of microelectronic devices is microlithography, which traces a microscopic-circuit pattern on the silicon wafer. In one typical process, a thin polymer film, typically less than a thickness 2 μm, is coated over the surface of the silicon wafer. A microscopic template, ...

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The strategy for solving this problem is to develo...

Question: 30.3

Trichloroethylene (TCE), a common industrial solvent, is often found at low concentrations in industrial waste waters. Stripping is a common process for removing sparingly soluble, volatile organic solutes such as TCE from aqueous solution. A wetted-wall column is used to study the stripping of TCE ...

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With this physical property information in hand, o...

Question: 30.1

Estimate the distance a spherical drop of liquid water, originally 1.0 mm in diameter, must fall in quiet, dry air at 323 K in order to reduce its volume by 50%. Assume that the velocity of the drop is its terminal velocity evaluated at its mean diameter and that the water temperature remains at ...

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The physical system requires a combined analysis o...

Question: 13.2

A heat exchanger is required, which will be able to handle 0.0567 m³/s of water through a smooth pipe with an equivalent length of 122 m. The total pressure drop is 103,000 Pa. What size pipe is required for this application? ...

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Once again, applying equation (6-10), we see that ...

Question: 24.4

Compare estimates the diffusion coefficient of an ethanol-water mixture at 10 C (283 K), under conditions that (1) ethanol is the solute and water is the solvent and (2) water is the solute and ethanol is the solvent. Ethanol has the molecular formula C2H5OH and a molecular weight of 46 g/gmole ...

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The Wilke–Chang correlation will be used for estim...