FORMULA LISTS Q̇cond = kA ΔT L Q̇ conv = hA(T∞ − TS ) 4 Q̇rad = εσA(Tsurr − TS4 ) Q̇ q̇ = A Ts, sphere = T∞ + ė gen 1 ∂ ∂T 1 ∂T (r ) + = r ∂r ∂r k α ∂t ė gen 1 ∂ 2 ∂T 1 ∂T (r )+ = 2 r ∂r ∂r k α ∂t ė gen L h 𝑇𝑐𝑒𝑛𝑡𝑒𝑟 = 𝑇0 = 𝑇𝑠 + ∆𝑇𝑚𝑎𝑥 ė gen r0 2h ∆𝑇𝑚𝑎𝑥, 𝑝𝑙𝑎𝑛𝑒 𝑤𝑎𝑙𝑙 = Ts, plane wall = T∞ + Ts, cylinder = T∞ + ∂2 T ė gen 1 ∂T + = 2 ∂x k α ∂t ė gen r0 3h 𝑒̇𝑔𝑒𝑛 𝐿2 2𝑘 𝑒̇𝑔𝑒𝑛 𝑟02 ∆𝑇𝑚𝑎𝑥, 𝑐𝑦𝑙𝑖𝑛𝑑𝑒𝑟 = 4𝑘 𝑒̇𝑔𝑒𝑛 𝑟02 ∆𝑇𝑚𝑎𝑥, 𝑠𝑝ℎ𝑒𝑟𝑒 = 6𝑘 R wall = Q̇ = T∞1 − T∞2 R total R cyl = ln(r2 ⁄r1 ) 2πLk R sph = r2 − r1 4πr1 r2 k ∆T = Q̇R rcr,cylinder = rcr,sphere = k ins h 2k ins h L kA R conv = R rad = 1 hA 1 hrad A 2 )(Ts + Tsurr ) hrad = εσ(Ts2 + Tsurr Bi = hLc < 0.1 k 𝐿𝑐 = 𝑉 𝐴𝑠 𝑇(𝑡) − 𝑇∞ = 𝑒 −𝑏𝑡 𝑇𝑖 − 𝑇∞ 𝑏= ℎ𝐴𝑠 ℎ = 𝜌𝑐𝑝 𝑉 𝜌𝑐𝑝 𝐿𝑐 𝜏 = 𝛼𝑡 𝑟𝑜 2 𝑄𝑚𝑎𝑥 = 𝑚𝑐𝑝 (𝑇∞ − 𝑇𝑖 ) ∑ Q̇ + ė Velement = 0 All sides Tm−1 − 2Tm + Tm+1 ė m + =0 (∆x)2 k Tleft + Ttop + Tright + Tbottom − 4Tnode + CD = FD 1 2 2 ρV A 𝑅𝑒 = 𝑇𝑓 = 𝑉𝐷 𝜈 𝑇𝑠 + 𝑇∞ 2 𝑁𝑢 = ℎ𝐿 𝑘 ė node ∆x∆y =0 k 251 CHAPTER 4 TABLE 4–2 TABLE 4–3 Coefficients used in the one-term approximate solution of transient onedimensional heat conduction in plane walls, cylinders, and spheres (Bi 5 hL/k for a plane wall of thickness 2L, and Bi 5 hro /k for a cylinder or sphere of radius ro ) The zeroth- and first-order Bessel functions of the first kind Bi 0.01 0.02 0.04 0.06 0.08 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 20.0 30.0 40.0 50.0 100.0 ` Plane Wall A1 l1 0.0998 0.1410 0.1987 0.2425 0.2791 0.3111 0.4328 0.5218 0.5932 0.6533 0.7051 0.7506 0.7910 0.8274 0.8603 1.0769 1.1925 1.2646 1.3138 1.3496 1.3766 1.3978 1.4149 1.4289 1.4961 1.5202 1.5325 1.5400 1.5552 1.5708 1.0017 1.0033 1.0066 1.0098 1.0130 1.0161 1.0311 1.0450 1.0580 1.0701 1.0814 1.0918 1.1016 1.1107 1.1191 1.1785 1.2102 1.2287 1.2403 1.2479 1.2532 1.2570 1.2598 1.2620 1.2699 1.2717 1.2723 1.2727 1.2731 1.2732 Cylinder Sphere l1 A1 l1 A1 0.1412 0.1995 0.2814 0.3438 0.3960 0.4417 0.6170 0.7465 0.8516 0.9408 1.0184 1.0873 1.1490 1.2048 1.2558 1.5995 1.7887 1.9081 1.9898 2.0490 2.0937 2.1286 2.1566 2.1795 2.2880 2.3261 2.3455 2.3572 2.3809 2.4048 1.0025 1.0050 1.0099 1.0148 1.0197 1.0246 1.0483 1.0712 1.0931 1.1143 1.1345 1.1539 1.1724 1.1902 1.2071 1.3384 1.4191 1.4698 1.5029 1.5253 1.5411 1.5526 1.5611 1.5677 1.5919 1.5973 1.5993 1.6002 1.6015 1.6021 0.1730 0.2445 0.3450 0.4217 0.4860 0.5423 0.7593 0.9208 1.0528 1.1656 1.2644 1.3525 1.4320 1.5044 1.5708 2.0288 2.2889 2.4556 2.5704 2.6537 2.7165 2.7654 2.8044 2.8363 2.9857 3.0372 3.0632 3.0788 3.1102 3.1416 1.0030 1.0060 1.0120 1.0179 1.0239 1.0298 1.0592 1.0880 1.1164 1.1441 1.1713 1.1978 1.2236 1.2488 1.2732 1.4793 1.6227 1.7202 1.7870 1.8338 1.8673 1.8920 1.9106 1.9249 1.9781 1.9898 1.9942 1.9962 1.9990 2.0000 temperature u0 drops by 20 percent at a specified time, so does the dimensionless temperature u0 anywhere else in the medium at the same time. Once the Bi number is known, these relations can be used to determine the temperature anywhere in the medium. The determination of the constants A1 and l1 usually requires interpolation. For those who prefer reading charts to interpolating, these relations are plotted and the one-term approximation solutions are presented in graphical form, known as the transient temperature charts. Note that the charts are sometimes difficult to read, and they are subject to reading errors. Therefore, the relations above should be preferred to the charts. The transient temperature charts in Figs. 4–17, 4–18, and 4–19 for a large plane wall, long cylinder, and sphere were presented by M. P. Heisler in 1947 and are called Heisler charts. They were supplemented in 1961 with transient h J0(h) J1(h) 0.0 0.1 0.2 0.3 0.4 1.0000 0.9975 0.9900 0.9776 0.9604 0.0000 0.0499 0.0995 0.1483 0.1960 0.5 0.6 0.7 0.8 0.9 0.9385 0.9120 0.8812 0.8463 0.8075 0.2423 0.2867 0.3290 0.3688 0.4059 1.0 1.1 1.2 1.3 1.4 0.7652 0.7196 0.6711 0.6201 0.5669 0.4400 0.4709 0.4983 0.5220 0.5419 1.5 1.6 1.7 1.8 1.9 0.5118 0.4554 0.3980 0.3400 0.2818 0.5579 0.5699 0.5778 0.5815 0.5812 2.0 2.1 2.2 2.3 2.4 0.2239 0.1666 0.1104 0.0555 0.0025 0.5767 0.5683 0.5560 0.5399 0.5202 2.6 2.8 3.0 3.2 20.0968 20.1850 20.2601 20.3202 0.4708 0.4097 0.3391 0.2613 252 TRANSIENT HEAT CONDUCTION T0 – T` Ti – T` 1.0 0.7 0.5 0.4 0.3 0.2 u0 = k hL = 1 Bi 1.0 0.7 0. 8 45 9 8 35 7 6 25 0.6 0.5 40 30 16 3 2 1.8 1.6 1.4 1.2 0.05 2.5 0 2 50 20 18 5 4 0.2 0.1 1 12 10 0.4 0.3 0.01 0.007 0.005 0.004 0.003 0.002 0 100 80 90 60 70 14 0.1 0.07 0.05 0.04 0.03 0.02 0.001 Plate 3 4 6 8 10 14 18 22 26 30 50 70 100 120 150 300 400 500 600 700 t = at/L2 T` h (a) Midplane temperature. From M. P. Heisler, “Temperature Charts for Induction and Constant Temperature Heating,” Trans. ASME 69, 1947, pp. 227–36. Reprinted by permission of ASME International. u T – T` = u0 T0 – T` x/L = 0.2 1.0 0.9 0.4 Bi = hL/k 0.4 0.8 50 20 10 5 2 1 0.5 0.05 0.1 0.2 0.3 0.9 0.1 1.0 0 0.01 0.1 0.00 5 0.01 0.02 0.5 0.2 x 2L 0.00 1 0.00 2 0.6 0.5 0.3 L 0.7 0.6 0.6 0.4 0 0.8 0.8 0.7 T` h Bi = 0.9 Q Qmax 1.0 Initially T = Ti 0.2 Plate 1.0 10 100 0.1 0 10–5 Plate 10– 4 1 k = Bi hL (b) Temperature distribution. (c) Heat transfer. From M. P. Heisler, “Temperature Charts for Induction and Constant Temperature Heating,” Trans. ASME 69, 1947, pp. 227–36. Reprinted by permission of ASME International. From H. Gröber et al. 10–3 10–2 10–1 1 Bi 2t = h2at/k 2 10 102 103 FIGURE 4–17 Transient temperature and heat transfer charts for a plane wall of thickness 2L initially at a uniform temperature Ti subjected to convection from both sides to an environment at temperature T` with a convection coefficient of h. 104 253 CHAPTER 4 u0 = T0 – T` Ti – T` 1.0 0.7 Cylinder 0.5 0.4 0.3 5 0.2 3.5 8 1. 16 = 1 Bi 25 20 12 1.6 90 18 70 14 10 0 80 60 9 1.2 50 10 7 0.8 0.6 8 45 35 30 0.3 0.1 0 0.5 6 40 0.4 0.2 0.01 0.007 0.005 0.004 0.003 3 2 1.4 1.0 0.02 k o 4 2. 5 0.1 0.07 0.05 0.04 0.03 hr 0.002 0 1 2 3 4 6 8 10 14 18 22 26 t = at/ro2 30 50 70 100 120 (a) Centerline temperature. Q Qmax 1.0 r/ro = 0.2 0.9 0.4 0.4 0.8 50 10 5 2 1 0.5 0.5 0.05 0.1 0.2 0.6 0.4 0.2 Bi = hro /k 0.7 0.6 0.5 0.3 ro r 0.8 0.7 0.6 0 0.00 1 0.00 2 0.00 5 0.01 0.02 0.8 0.9 350 Bi = 1.0 250 T` Initially T` h T = Ti h From M. P. Heisler, “Temperature Charts for Induction and Constant Temperature Heating,” Trans. ASME 69, 1947, pp. 227–36. Reprinted by permission of ASME International. u T – T` = u 0 T0 – T` 140 150 20 0.001 0.3 0.2 0.9 0.1 1.0 0 0.1 0.01 1.0 1 k = Bi hro (b) Temperature distribution. Cylinder 10 From M. P. Heisler, “Temperature Charts for Induction and Constant Temperature Heating,” Trans. ASME 69, 1947, pp. 227–36. Reprinted by permission of ASME International. 100 0.1 0 10–5 Cylinder 10– 4 10–3 10–2 10–1 1 Bi 2t = h2at/k 2 10 102 103 104 (c) Heat transfer. From H. Gröber et al. FIGURE 4–18 Transient temperature and heat transfer charts for a long cylinder of radius ro initially at a uniform temperature Ti subjected to convection from all sides to an environment at temperature T` with a convection coefficient of h. 254 TRANSIENT HEAT CONDUCTION T0 – T` Ti – T` 1.0 0.7 0.5 0.4 0.3 hr 0.2 100 80 90 60 70 12 14 Sphere = 1 Bi 25 20 18 16 6 50 40 45 0 35 3 10 8 9 7 5 3.5 4 1.2 5 0.7 0.5 0.01 0.007 0.005 0.004 0.003 1.6 1.4 1.0 0.02 3.0 2.6 2 .8 2.4 .0 2 2 2. 8 1. 0.1 0.07 0.05 0.04 0.03 0 0.35 0.2 0.1 0.05 0.002 0 0.5 1.0 1.5 2 2.5 3 4 5 6 7 8 9 10 t = at/ro2 20 30 40 T` h (a) Midpoint temperature. From M. P. Heisler, “Temperature Charts for Induction and Constant Temperature Heating,” Trans. ASME 69, 1947, pp. 227–36. Reprinted by permission of ASME International. u T – T` = u0 T0 – T` r/ro = 0.2 0.9 0.9 0.4 T` h 0 ro 250 r 0.4 0.4 0.3 0.8 0.3 0.2 0.9 0.2 0.1 1.0 1.0 10 1 = k Bi hro (b) Temperature distribution. From M. P. Heisler, “Temperature Charts for Induction and Constant Temperature Heating,” Trans. ASME 69, 1947, pp. 227–36. Reprinted by permission of ASME International. 50 20 10 0.1 Sphere 0.1 0.5 1 0.5 0.05 0.1 0.2 0.6 0.6 0.00 5 0.01 0.02 0.7 0.5 0 0.01 Initially T = Ti 200 0.8 0.7 0.6 150 Bi = hro /k 0.00 1 0.00 2 0.8 100 Bi = 1.0 Q Qmax 1.0 50 5 0.001 k o 2 u0 = 100 0 10–5 Sphere 10– 4 10–3 10–2 10–1 1 10 102 103 Bi 2t = h2a t/k 2 (c) Heat transfer. From H. Gröber et al. FIGURE 4–19 Transient temperature and heat transfer charts for a sphere of radius ro initially at a uniform temperature Ti subjected to convection from all sides to an environment at temperature T` with a convection coefficient of h. 104 443 CHAPTER 7 The characteristic length D for use in the calculation of the Reynolds and the Nusselt numbers for different geometries is as indicated on the figure. All fluid properties are evaluated at the film temperature. Note that the values presented in Table 7–1 for non-circular geometrics have been updated based on the recommendations of Sparrow et al. (2004). TABLE 7–1 Empirical correlations for the average Nusselt number for forced convection over circular and noncircular cylinders in cross flow (from Zukauskas, 1972, Jakob 1949, and Sparrow et al., 2004) Cross-section of the cylinder Fluid Range of Re Nusselt number Gas or liquid 0.4–4 4–40 40–4000 4000–40,000 40,000–400,000 Nu 5 0.989Re0.330 Pr1/3 Nu 5 0.911Re0.385 Pr1/3 Nu 5 0.683Re0.466 Pr1/3 Nu 5 0.193Re0.618 Pr1/3 Nu 5 0.027Re0.805 Pr1/3 Gas 3900–79,000 Nu 5 0.094Re0.675 Pr1/3 Gas 5600–111,000 Nu 5 0.258Re0.588 Pr1/3 Gas 4500–90,700 Nu 5 0.148Re0.638 Pr1/3 Gas 5200–20,400 20,400–105,000 Nu 5 0.162Re0.638 Pr1/3 Nu 5 0.039Re0.782 Pr1/3 Gas 6300–23,600 Nu 5 0.257Re0.731 Pr1/3 Gas 1400–8200 Nu 5 0.197Re0.612 Pr1/3 Circle D Square D Square (tilted 45°) D Hexagon D Hexagon (tilted 45°) Vertical plate D D Ellipse D cen98128_App-A_p865-892.qxd 1/8/10 3:29 PM Page 878 878 APPENDIX 1 TABLE A–9 Properties of saturated water Temp. T, ⬚C 0.01 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 110 120 130 140 150 160 170 180 190 200 220 240 260 280 300 320 340 360 374.14 Saturation Pressure Psat, kPa 0.6113 0.8721 1.2276 1.7051 2.339 3.169 4.246 5.628 7.384 9.593 12.35 15.76 19.94 25.03 31.19 38.58 47.39 57.83 70.14 84.55 101.33 143.27 198.53 270.1 361.3 475.8 617.8 791.7 1,002.1 1,254.4 1,553.8 2,318 3,344 4,688 6,412 8,581 11,274 14,586 18,651 22,090 Density r, kg/m3 Enthalpy of Vaporization Specific Heat cp, J/kg·K Thermal Conductivity k, W/m·K Liquid Vapor hfg, kJ/kg Liquid Vapor 999.8 0.0048 999.9 0.0068 999.7 0.0094 999.1 0.0128 998.0 0.0173 997.0 0.0231 996.0 0.0304 994.0 0.0397 992.1 0.0512 990.1 0.0655 988.1 0.0831 985.2 0.1045 983.3 0.1304 980.4 0.1614 977.5 0.1983 974.7 0.2421 971.8 0.2935 968.1 0.3536 965.3 0.4235 961.5 0.5045 957.9 0.5978 950.6 0.8263 943.4 1.121 934.6 1.496 921.7 1.965 916.6 2.546 907.4 3.256 897.7 4.119 887.3 5.153 876.4 6.388 864.3 7.852 840.3 11.60 813.7 16.73 783.7 23.69 750.8 33.15 713.8 46.15 667.1 64.57 610.5 92.62 528.3 144.0 317.0 317.0 2501 2490 2478 2466 2454 2442 2431 2419 2407 2395 2383 2371 2359 2346 2334 2321 2309 2296 2283 2270 2257 2230 2203 2174 2145 2114 2083 2050 2015 1979 1941 1859 1767 1663 1544 1405 1239 1028 720 0 4217 4205 4194 4185 4182 4180 4178 4178 4179 4180 4181 4183 4185 4187 4190 4193 4197 4201 4206 4212 4217 4229 4244 4263 4286 4311 4340 4370 4410 4460 4500 4610 4760 4970 5280 5750 6540 8240 14,690 — 1854 1857 1862 1863 1867 1870 1875 1880 1885 1892 1900 1908 1916 1926 1936 1948 1962 1977 1993 2010 2029 2071 2120 2177 2244 2314 2420 2490 2590 2710 2840 3110 3520 4070 4835 5980 7900 11,870 25,800 — Liquid Vapor 0.561 0.0171 0.571 0.0173 0.580 0.0176 0.589 0.0179 0.598 0.0182 0.607 0.0186 0.615 0.0189 0.623 0.0192 0.631 0.0196 0.637 0.0200 0.644 0.0204 0.649 0.0208 0.654 0.0212 0.659 0.0216 0.663 0.0221 0.667 0.0225 0.670 0.0230 0.673 0.0235 0.675 0.0240 0.677 0.0246 0.679 0.0251 0.682 0.0262 0.683 0.0275 0.684 0.0288 0.683 0.0301 0.682 0.0316 0.680 0.0331 0.677 0.0347 0.673 0.0364 0.669 0.0382 0.663 0.0401 0.650 0.0442 0.632 0.0487 0.609 0.0540 0.581 0.0605 0.548 0.0695 0.509 0.0836 0.469 0.110 0.427 0.178 — — Dynamic Viscosity m, kg/m·s Prandtl Number Pr Volume Expansion Coefficient b, 1/K Liquid Vapor Liquid Vapor 1.792 ⫻ 10⫺3 1.519 ⫻ 10⫺3 1.307 ⫻ 10⫺3 1.138 ⫻ 10⫺3 1.002 ⫻ 10⫺3 0.891 ⫻ 10⫺3 0.798 ⫻ 10⫺3 0.720 ⫻ 10⫺3 0.653 ⫻ 10⫺3 0.596 ⫻ 10⫺3 0.547 ⫻ 10⫺3 0.504 ⫻ 10⫺3 0.467 ⫻ 10⫺3 0.433 ⫻ 10⫺3 0.404 ⫻ 10⫺3 0.378 ⫻ 10⫺3 0.355 ⫻ 10⫺3 0.333 ⫻ 10⫺3 0.315 ⫻ 10⫺3 0.297 ⫻ 10⫺3 0.282 ⫻ 10⫺3 0.255 ⫻ 10⫺3 0.232 ⫻ 10⫺3 0.213 ⫻ 10⫺3 0.197 ⫻ 10⫺3 0.183 ⫻ 10⫺3 0.170 ⫻ 10⫺3 0.160 ⫻ 10⫺3 0.150 ⫻ 10⫺3 0.142 ⫻ 10⫺3 0.134 ⫻ 10⫺3 0.122 ⫻ 10⫺3 0.111 ⫻ 10⫺3 0.102 ⫻ 10⫺3 0.094 ⫻ 10⫺3 0.086 ⫻ 10⫺3 0.078 ⫻ 10⫺3 0.070 ⫻ 10⫺3 0.060 ⫻ 10⫺3 0.043 ⫻ 10⫺3 0.922 ⫻ 10⫺5 0.934 ⫻ 10⫺5 0.946 ⫻ 10⫺5 0.959 ⫻ 10⫺5 0.973 ⫻ 10⫺5 0.987 ⫻ 10⫺5 1.001 ⫻ 10⫺5 1.016 ⫻ 10⫺5 1.031 ⫻ 10⫺5 1.046 ⫻ 10⫺5 1.062 ⫻ 10⫺5 1.077 ⫻ 10⫺5 1.093 ⫻ 10⫺5 1.110 ⫻ 10⫺5 1.126 ⫻ 10⫺5 1.142 ⫻ 10⫺5 1.159 ⫻ 10⫺5 1.176 ⫻ 10⫺5 1.193 ⫻ 10⫺5 1.210 ⫻ 10⫺5 1.227 ⫻ 10⫺5 1.261 ⫻ 10⫺5 1.296 ⫻ 10⫺5 1.330 ⫻ 10⫺5 1.365 ⫻ 10⫺5 1.399 ⫻ 10⫺5 1.434 ⫻ 10⫺5 1.468 ⫻ 10⫺5 1.502 ⫻ 10⫺5 1.537 ⫻ 10⫺5 1.571 ⫻ 10⫺5 1.641 ⫻ 10⫺5 1.712 ⫻ 10⫺5 1.788 ⫻ 10⫺5 1.870 ⫻ 10⫺5 1.965 ⫻ 10⫺5 2.084 ⫻ 10⫺5 2.255 ⫻ 10⫺5 2.571 ⫻ 10⫺5 4.313 ⫻ 10⫺5 13.5 11.2 9.45 8.09 7.01 6.14 5.42 4.83 4.32 3.91 3.55 3.25 2.99 2.75 2.55 2.38 2.22 2.08 1.96 1.85 1.75 1.58 1.44 1.33 1.24 1.16 1.09 1.03 0.983 0.947 0.910 0.865 0.836 0.832 0.854 0.902 1.00 1.23 2.06 1.00 ⫺0.068 ⫻ 10⫺3 1.00 0.015 ⫻ 10⫺3 1.00 0.733 ⫻ 10⫺3 1.00 0.138 ⫻ 10⫺3 1.00 0.195 ⫻ 10⫺3 1.00 0.247 ⫻ 10⫺3 1.00 0.294 ⫻ 10⫺3 1.00 0.337 ⫻ 10⫺3 1.00 0.377 ⫻ 10⫺3 1.00 0.415 ⫻ 10⫺3 1.00 0.451 ⫻ 10⫺3 1.00 0.484 ⫻ 10⫺3 1.00 0.517 ⫻ 10⫺3 1.00 0.548 ⫻ 10⫺3 1.00 0.578 ⫻ 10⫺3 1.00 0.607 ⫻ 10⫺3 1.00 0.653 ⫻ 10⫺3 1.00 0.670 ⫻ 10⫺3 1.00 0.702 ⫻ 10⫺3 1.00 0.716 ⫻ 10⫺3 1.00 0.750 ⫻ 10⫺3 1.00 0.798 ⫻ 10⫺3 1.00 0.858 ⫻ 10⫺3 1.01 0.913 ⫻ 10⫺3 1.02 0.970 ⫻ 10⫺3 1.02 1.025 ⫻ 10⫺3 1.05 1.145 ⫻ 10⫺3 1.05 1.178 ⫻ 10⫺3 1.07 1.210 ⫻ 10⫺3 1.09 1.280 ⫻ 10⫺3 1.11 1.350 ⫻ 10⫺3 1.15 1.520 ⫻ 10⫺3 1.24 1.720 ⫻ 10⫺3 1.35 2.000 ⫻ 10⫺3 1.49 2.380 ⫻ 10⫺3 1.69 2.950 ⫻ 10⫺3 1.97 2.43 3.73 Liquid Note 1: Kinematic viscosity n and thermal diffusivity a can be calculated from their definitions, n ⫽ m/r and a ⫽ k/rcp ⫽ n/Pr. The temperatures 0.01⬚C, 100⬚C, and 374.14⬚C are the triple-, boiling-, and critical-point temperatures of water, respectively. The properties listed above (except the vapor density) can be used at any pressure with negligible error except at temperatures near the critical-point value. Note 2: The unit kJ/kg·⬚C for specific heat is equivalent to kJ/kg·K, and the unit W/m·⬚C for thermal conductivity is equivalent to W/m·K. Source: Viscosity and thermal conductivity data are from J. V. Sengers and J. T. R. Watson, Journal of Physical and Chemical Reference Data 15 (1986), pp. 1291–1322. Other data are obtained from various sources or calculated. cen98128_App-A_p865-892.qxd 1/8/10 3:29 PM Page 884 884 APPENDIX 1 TABLE A–15 Properties of air at 1 atm pressure Temp. T, ⬚C Density r, kg/m3 Specific Heat cp, J/kg·K Thermal Conductivity k, W/m·K Thermal Diffusivity a, m2/s Dynamic Viscosity m, kg/m·s Kinematic Viscosity n, m2/s Prandtl Number Pr ⫺150 ⫺100 ⫺50 ⫺40 ⫺30 ⫺20 ⫺10 0 5 10 15 20 25 30 35 40 45 50 60 70 80 90 100 120 140 160 180 200 250 300 350 400 450 500 600 700 800 900 1000 1500 2000 2.866 2.038 1.582 1.514 1.451 1.394 1.341 1.292 1.269 1.246 1.225 1.204 1.184 1.164 1.145 1.127 1.109 1.092 1.059 1.028 0.9994 0.9718 0.9458 0.8977 0.8542 0.8148 0.7788 0.7459 0.6746 0.6158 0.5664 0.5243 0.4880 0.4565 0.4042 0.3627 0.3289 0.3008 0.2772 0.1990 0.1553 983 966 999 1002 1004 1005 1006 1006 1006 1006 1007 1007 1007 1007 1007 1007 1007 1007 1007 1007 1008 1008 1009 1011 1013 1016 1019 1023 1033 1044 1056 1069 1081 1093 1115 1135 1153 1169 1184 1234 1264 0.01171 0.01582 0.01979 0.02057 0.02134 0.02211 0.02288 0.02364 0.02401 0.02439 0.02476 0.02514 0.02551 0.02588 0.02625 0.02662 0.02699 0.02735 0.02808 0.02881 0.02953 0.03024 0.03095 0.03235 0.03374 0.03511 0.03646 0.03779 0.04104 0.04418 0.04721 0.05015 0.05298 0.05572 0.06093 0.06581 0.07037 0.07465 0.07868 0.09599 0.11113 4.158 ⫻ 10⫺6 8.036 ⫻ 10⫺6 1.252 ⫻ 10⫺5 1.356 ⫻ 10⫺5 1.465 ⫻ 10⫺5 1.578 ⫻ 10⫺5 1.696 ⫻ 10⫺5 1.818 ⫻ 10⫺5 1.880 ⫻ 10⫺5 1.944 ⫻ 10⫺5 2.009 ⫻ 10⫺5 2.074 ⫻ 10⫺5 2.141 ⫻ 10⫺5 2.208 ⫻ 10⫺5 2.277 ⫻ 10⫺5 2.346 ⫻ 10⫺5 2.416 ⫻ 10⫺5 2.487 ⫻ 10⫺5 2.632 ⫻ 10⫺5 2.780 ⫻ 10⫺5 2.931 ⫻ 10⫺5 3.086 ⫻ 10⫺5 3.243 ⫻ 10⫺5 3.565 ⫻ 10⫺5 3.898 ⫻ 10⫺5 4.241 ⫻ 10⫺5 4.593 ⫻ 10⫺5 4.954 ⫻ 10⫺5 5.890 ⫻ 10⫺5 6.871 ⫻ 10⫺5 7.892 ⫻ 10⫺5 8.951 ⫻ 10⫺5 1.004 ⫻ 10⫺4 1.117 ⫻ 10⫺4 1.352 ⫻ 10⫺4 1.598 ⫻ 10⫺4 1.855 ⫻ 10⫺4 2.122 ⫻ 10⫺4 2.398 ⫻ 10⫺4 3.908 ⫻ 10⫺4 5.664 ⫻ 10⫺4 8.636 ⫻ 10⫺6 1.189 ⫻ 10⫺5 1.474 ⫻ 10⫺5 1.527 ⫻ 10⫺5 1.579 ⫻ 10⫺5 1.630 ⫻ 10⫺5 1.680 ⫻ 10⫺5 1.729 ⫻ 10⫺5 1.754 ⫻ 10⫺5 1.778 ⫻ 10⫺5 1.802 ⫻ 10⫺5 1.825 ⫻ 10⫺5 1.849 ⫻ 10⫺5 1.872 ⫻ 10⫺5 1.895 ⫻ 10⫺5 1.918 ⫻ 10⫺5 1.941 ⫻ 10⫺5 1.963 ⫻ 10⫺5 2.008 ⫻ 10⫺5 2.052 ⫻ 10⫺5 2.096 ⫻ 10⫺5 2.139 ⫻ 10⫺5 2.181 ⫻ 10⫺5 2.264 ⫻ 10⫺5 2.345 ⫻ 10⫺5 2.420 ⫻ 10⫺5 2.504 ⫻ 10⫺5 2.577 ⫻ 10⫺5 2.760 ⫻ 10⫺5 2.934 ⫻ 10⫺5 3.101 ⫻ 10⫺5 3.261 ⫻ 10⫺5 3.415 ⫻ 10⫺5 3.563 ⫻ 10⫺5 3.846 ⫻ 10⫺5 4.111 ⫻ 10⫺5 4.362 ⫻ 10⫺5 4.600 ⫻ 10⫺5 4.826 ⫻ 10⫺5 5.817 ⫻ 10⫺5 6.630 ⫻ 10⫺5 3.013 ⫻ 10⫺6 5.837 ⫻ 10⫺6 9.319 ⫻ 10⫺6 1.008 ⫻ 10⫺5 1.087 ⫻ 10⫺5 1.169 ⫻ 10⫺5 1.252 ⫻ 10⫺5 1.338 ⫻ 10⫺5 1.382 ⫻ 10⫺5 1.426 ⫻ 10⫺5 1.470 ⫻ 10⫺5 1.516 ⫻ 10⫺5 1.562 ⫻ 10⫺5 1.608 ⫻ 10⫺5 1.655 ⫻ 10⫺5 1.702 ⫻ 10⫺5 1.750 ⫻ 10⫺5 1.798 ⫻ 10⫺5 1.896 ⫻ 10⫺5 1.995 ⫻ 10⫺5 2.097 ⫻ 10⫺5 2.201 ⫻ 10⫺5 2.306 ⫻ 10⫺5 2.522 ⫻ 10⫺5 2.745 ⫻ 10⫺5 2.975 ⫻ 10⫺5 3.212 ⫻ 10⫺5 3.455 ⫻ 10⫺5 4.091 ⫻ 10⫺5 4.765 ⫻ 10⫺5 5.475 ⫻ 10⫺5 6.219 ⫻ 10⫺5 6.997 ⫻ 10⫺5 7.806 ⫻ 10⫺5 9.515 ⫻ 10⫺5 1.133 ⫻ 10⫺4 1.326 ⫻ 10⫺4 1.529 ⫻ 10⫺4 1.741 ⫻ 10⫺4 2.922 ⫻ 10⫺4 4.270 ⫻ 10⫺4 0.7246 0.7263 0.7440 0.7436 0.7425 0.7408 0.7387 0.7362 0.7350 0.7336 0.7323 0.7309 0.7296 0.7282 0.7268 0.7255 0.7241 0.7228 0.7202 0.7177 0.7154 0.7132 0.7111 0.7073 0.7041 0.7014 0.6992 0.6974 0.6946 0.6935 0.6937 0.6948 0.6965 0.6986 0.7037 0.7092 0.7149 0.7206 0.7260 0.7478 0.7539 Note: For ideal gases, the properties cp, k, m, and Pr are independent of pressure. The properties r, n, and a at a pressure P (in atm) other than 1 atm are determined by multiplying the values of r at the given temperature by P and by dividing n and a by P. Source: Data generated from the EES software developed by S. A. Klein and F. L. Alvarado. Original sources: Keenan, Chao, Keyes, Gas Tables, Wiley, 1984; and Thermophysical Properties of Matter. Vol. 3: Thermal Conductivity, Y. S. Touloukian, P. E. Liley, S. C. Saxena, Vol. 11: Viscosity, Y. S. Touloukian, S. C. Saxena, and P. Hestermans, IFI/Plenun, NY, 1970, ISBN 0-306067020-8.