fundamentals of heat and mass transfer solutions manual phần 9 ppt

... history of theworkpiece from the start of heating to the end of cooling; identify key features of the process;determine the total time requirement; and justify the lumped-capacitance method of analysis.SCHEMATIC:ASSUMPTIONS: ... M is the mass of PCM, and hfg is the heat of fusion of PCM.Irradiation: G = σTw = 5.67 × 10-8 W/m2⋅K4(1200 K)4 = 117,573 W/m2Emissive power: Eb = ( )442mT8727 395 2W/mσσ=+=Emissivity: ... and diffuse, (2) Spectral emissivity is independent of temperature, and (3) Furnace and cooling environment are large isothermal surroundings.ANALYSIS: (a) Using Eqs. 12.38 and 12.46, ε and...

fundamentals of heat and mass transfer solutions manual phần 2 docx

... Temperature and volume of hot water heater. Nature of heater insulating material. Ambientair temperature and convection coefficient. Unit cost of electric power.FIND: Heater dimensions and insulation ... through a pipe of prescribed inner and outer radii. Emissivity of outer surface magnesia insulation, and convectioncoefficient. Temperature of ambient air and surroundings.FIND: Heat loss per ... radius.PROBLEM 3.43KNOWN: Diameter of electrical wire. Thickness and thermal conductivity of rubberized sheath.Contact resistance between sheath and wire. Convection coefficient and ambient air temperature.Maximum...

fundamentals of heat and mass transfer solutions manual phần 3 pdf

... To and T∞, the relative amounts of heat transfer to the air and heat sinkare determined by the values of h and t,cR.′′PROBLEM 4.54 (Cont.)The heat rate by convection between the bar and ... 243.1 235.0 223 .9 2 09. 8 194 .1 177.8100 282.4 281.8 280.1 276 .9 271.6 263.3 250.5 232.8 213.5125 310 .9 310.5 3 09. 3 307.1 303.2 296 .0 282.2 257.5150 340.0 340.0 3 39. 6 3 39. 1 337 .9 335.3 324.7Agreement ... -50 86.0 105.6 1 19 131.7 151.6 20050 88.2 117.4 138.7 156.1 174.6 20050 99 .6 137.1 162.5 1 79. 2 190 .8 20050 123.0 168 .9 194 .9 207.6 2 09. 4 20050 173.4 220.7 240.6 246.8 2 39. 0 200- 300 300...

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fundamentals of heat and mass transfer solutions manual phần 4 docx

... (L,45s)(mm)(°C)kW/m2kW/m210 1 49. 8 -2 49. 8 +1 49. 85 1 49. 3 -2 49. 0 +1 49. 02 1 49. 4 -2 49. 1 +1 49. 0COMMENTS: (1) The center temperature and boundary heat fluxes are quite insensitive to mesh ... 322.7 324.0 324.5 325 7 126 281.8 299 .5 310.5 317 .9 321.4 323.3 324.2 8 144 2 79. 8 296 .2 308.6 315.8 320.4 322.5 9 162 276.7 294 .1 306.0 314.3 3 19. 010 180 274.8 291 .3 304.1 312.4Hence, find( ... 120 s) and T(0.15 m, 120s) using the finite-element software FEHTfor a surface emissivity of 0 .94 and (b) Plot the temperature histories for x = 0, 150 and 600 mm, and explain key features of your...

fundamentals of heat and mass transfer solutions manual phần 5 ppsx

... emissivity of Nichrome wire. Electricalcurrent. Temperature of air flow and surroundings. Velocity of air flow. (a) Surface and centerline temperatures of the wire, (b) Effect of flow velocity and ... thickness and thermal conductivity of steel pipe. Temperature of water flow inpipe. Temperature and velocity of air in cross flow over pipe. Cost of producing hot water. (a) Cost of daily heat loss ... Diameter and length of a copper rod, with fixed end temperatures, inserted in an airstream of prescribed velocity and temperature.FIND: (a) Midplane temperature of rod, (b) Rate of heat transfer...

fundamentals of heat and mass transfer solutions manual phần 6 docx

... 1000 3.025 × 10-2348.6 91 5.0 2 95 0 4.321 × 10-2463.7 898 . 3 90 0 5.041 × 10-2524.6 891 .0 4 890 5.215 × 10-25 39. 0 8 89. 5Hence, we find2am,om5.2210 kg/s T 890 K.−=×=&<COMMENTS: ... 8.34KNOWN: Flow rate and inlet temperature of water passing through a tube of prescribed length,diameter and surface temperature.FIND: (a) Outlet water temperature and rate of heat transfer to water ... 4660s 1.29h7500Wπ××−=×==<Continued PROBLEM 8.28KNOWN: Inlet temperature, flow rate and properties of hot fluid. Initial temperature, volume and properties of pharmaceutical. Heat transfer...

fundamentals of heat and mass transfer solutions manual phần 7 pot

... )D1/451/4D4 /94 /9 9/1 69/ 160.5 892 .93 100.589RaNu2212.5510.4 69/ Pr10.4 69/ 0.700×=+=+=++( )D2hNuk/D12.550.0 298 W/mK/0.040m9.36W/mK.==⋅=⋅Substituting numerical values, the heat loss ... onquality, x, at outlet of 30 m length of tube; (b) Effect of radiation on heat transfer and quality of outletflow; (c) Effect of emissivity and insulation thickness on heat rate.SCHEMATIC:ASSUMPTIONS: ... Eq. 9. 35, is()1/4DD4 /9 9/160.589RaNu 21 0.4 69 Pr=++Continued PROBLEM 9. 70 (Cont.)/* Correlation description: Free convection (FC) for a vertical plate (VP), Eqs 9. 25 and 9. 26...

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fundamentals of heat and mass transfer solutions manual phần 8 ppsx

... Cr = 0.5 and NTU = 2 to obtain ε = 0. 693 .PROBLEM 11. 39 KNOWN: Pressure and initial flow rate of water vapor. Water inlet and outlet temperatures. Initial and final overall heat transfer coefficients.FIND: ... values of P and R as given by Fig. 11.11 with()()()()P9535/300350.23R300 196 /120351.22=−−==−−=giving F ≈ 1. Based upon CF arrangement,()()()()m,CFT30 095 196 35C/n30 095 / 196 .235182K.∆=−−−°−−=llUsing ... (a) Overall heat transfer coefficient, U, for the HXer, outlet temperature of cooling water, Tc,o, and condensation rate of the steam hm; and (b) Compute and plot Tc,o and hm as...

fundamentals of heat and mass transfer solutions manual phần 10 doc

... of ash deposit. Convection coefficient and temperature of gas flow over the tube. Temperature of surroundings.FIND: (a) Rate of heat transfer to tube without ash deposit, (b) Rate of heat transfer ... 13.1 09 KNOWN: Dimensions and emissivity of double pane window. Thickness of air gap. Temperatures of room and ambient air and the related surroundings.FIND: (a) Temperatures of glass panes and ... Do(m)050100150200 Heat rates (W/m)Radiation heat rate (W/m)Convection heat rate (W/m)Total heat rate (W/m)PROBLEM 13.107KNOWN: Thickness and height of a vertical air space. Emissivity and temperature of...

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