What is the skin-friction coefficient for a turbulent boundary layer on a flat plate, when M_e=2.5, \operatorname{Re}_x=6.142 \times 10^6, and T_w=3.0 T_e ?
For these calculations,
F_c=2.056(\text { see Table 8.4) }
and
F_{\mathrm{Re}}=0.1729(\text { see Table 8.5) }
Thus,
\mathrm{Re}_x F_{\mathrm{Re}}=1.062 \times 10^6
Using Table 8.6, we obtain
F_c C_f=0.0035
so that
C_f=1.70 \times 10^{-3}
M_e | |||||||
\frac{T_w}{T_{\mathrm{e}}} | 0.0 | 1.0 | 2.0 | 3.0 | 4.0 | 5.0 | 6.0 |
0.05 | 0.3743 | 0.4036 | 0.4884 | 0.6222 | 0.7999 | 1.0184 | 1.2759 |
0.10 | 0.4331 | 0.4625 | 0.5477 | 0.6829 | 0.8628 | 1.0842 | 1.3451 |
0.20 | 0.5236 | 0.5530 | 0.6388 | 0.7756 | 0.9584 | 1.1836 | 1.4491 |
0.30 | 0.5989 | 0.6283 | 0.7145 | 0.8523 | 1.0370 | 1.2649 | 1.5337 |
0.40 | 0.6662 | 0.6957 | 0.7821 | 0.9208 | 1.1069 | 1.3370 | 1.6083 |
0.50 | 0.7286 | 0.7580 | 0.8446 | 0.9839 | 1.1713 | 1.4031 | 1.6767 |
0.60 | 0.7873 | 0.8168 | 0.9036 | 1.0434 | 1.2318 | 1.4651 | 1.7405 |
0.80 | 0.8972 | 0.9267 | 1.0137 | 1.1544 | 1.3445 | 1.5802 | 1.8589 |
1.00 | 1.0000 | 1.0295 | 1.1167 | 1.2581 | 1.4494 | 1.6871 | 1.9684 |
2.00 | 1.4571 | 1.4867 | 1.5744 | 1.7176 | 1.9130 | 2.1572 | 2.4472 |
3.00 | 1.8660 | 1.8956 | 1.9836 | 2.1278 | 2.3254 | 2.5733 | 2.8687 |
4.00 | 2.2500 | 2.2796 | 2.3678 | 2.5126 | 2.7117 | 2.9621 | 3.2611 |
5.00 | 2.6180 | 2.6477 | 2.7359 | 2.8812 | 3.0813 | 3.3336 | 3.6355 |
6.00 | 2.9747 | 3.0044 | 3.0927 | 3.2384 | 3.4393 | 3.6930 | 3.9971 |
8.00 | 3.6642 | 3.6938 | 3.7823 | 3.9284 | 4.1305 | 4.3863 | 4.6937 |
10.00 | 4.3311 | 4.3608 | 4.4493 | 4.5958 | 4.7986 | 5.0559 | 5.3657 |
Source: Spalding and Chi (1964).
\text { TABLE 8.5 Values of } F_{\mathrm{Re}} \text { as a Function of } M_{\mathrm{e}} \text { and } T_w / T_{\mathrm{e}}M_e | |||||||
\frac{T_w}{T_{\mathrm{e}}} | 0.0 | 1.0 | 2.0 | 3.0 | 4.0 | 5.0 | 6.0 |
0.05 | 221.0540 | 232.6437 | 256.5708 | 278.2309 | 292.7413 | 300.8139 | 304.3061 |
0.10 | 68.9263 | 73.0824 | 82.3611 | 91.2557 | 97.6992 | 101.7158 | 103.9093 |
0.20 | 20.4777 | 22.0029 | 25.4203 | 28.9242 | 31.6618 | 33.5409 | 34.7210 |
0.30 | 9.8486 | 10.6532 | 12.5022 | 14.4793 | 16.0970 | 17.2649 | 18.0465 |
0.40 | 5.7938 | 6.2960 | 7.4742 | 8.7703 | 9.8686 | 10.6889 | 11.2618 |
0.50 | 3.8127 | 4.1588 | 4.9812 | 5.9072 | 6.7120 | 7.3304 | 7.7745 |
0.60 | 2.6969 | 2.9499 | 3.5588 | 4.2576 | 4.8783 | 5.3658 | 5.7246 |
0.80 | 1.5487 | 1.7015 | 2.0759 | 2.5183 | 2.9247 | 3.2556 | 3.5076 |
1.00 | 1.0000 | 1.1023 | 1.3562 | 1.6631 | 1.9526 | 2.1946 | 2.3840 |
2.00 | 0.2471 | 0.2748 | 0.3463 | 0.4385 | 0.5326 | 0.6178 | 0.6903 |
3.00 | 0.1061 | 0.1185 | 0.1512 | 0.1947 | 0.2410 | 0.2849 | 0.3239 |
4.00 | 0.0576 | 0.0645 | 0.0829 | 0.1079 | 0.1352 | 0.1620 | 0.1865 |
5.00 | 0.0356 | 0.0400 | 0.0516 | 0.0677 | 0.0856 | 0.1036 | 0.1204 |
6.00 | 0.0240 | 0.0269 | 0.0349 | 0.0460 | 0.0586 | 0.0715 | 0.0834 |
8.00 | 0.0127 | 0.0143 | 0.0187 | 0.0248 | 0.0320 | 0.0394 | 0.0466 |
10.00 | 0.0078 | 0.0087 | 0.0114 | 0.0153 | 0.0198 | 0.0246 | 0.0294 |
F_c C_f | F_{\mathrm{Re}} \mathrm{Re}_{\mathrm{x}} | F_c C_f | F_{\mathrm{Re}} \mathrm{Re}_{\mathrm{x}} |
0.0010 | 5.758 \times 10^{10} | 0.0055 | 8.697 \times 10^4 |
0.0015 | 4.610 \times 10^8 | 0.0060 | 5.679 \times 10^4 |
0.0020 | 4.651 \times 10^7 | 0.0065 | 3.901 \times 10^4 |
0.0025 | 9.340 \times 10^6 | 0.0070 | 2.796 \times 10^4 |
0.0030 | 2.778 \times 10^6 | 0.0075 | 2.078 \times 10^4 |
0.0035 | 1.062 \times 10^6 | 0.0080 | 1.592 \times 10^4 |
0.0040 | 4.828 \times 10^5 | 0.0085 | 1.251 \times 10^4 |
0.0045 | 2.492 \times 10^5 | 0.0090 | 1.006 \times 10^4 |
0.0050 | 1.417 \times 10^5 |
Source: Spalding and Chi (1964).