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Tham khảo tài liệu 'a heat transfer textbook - third edition episode 3 part 2', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 514 Chapter 9 Heat transfer in boiling and other phase-change configurations 9.9 Water at 100 atm boils on a nickel heater whose temperature is 6 C above Tsat. Find h and q. 9.10 Water boils on a large flat plate at 1 atm. Calculate qmax if the plate is operated on the surface of the moon at 6 of dearth-normal . What would qmax be in a space vehicle experiencing 10 4 of dearth-normal 9.11 Water boils on a 0.002 m diameter horizontal copper wire. Plot to scale as much of the boiling curve on log q vs. log AT coordinates as you can. The system is at 1 atm. 9.12 Redo Problem 9.11 for a 0.03 m diameter sphere in water at 10 atm. 9.13 Verify eqn. 9.17 . 9.14 Make a sketch of the q vs. Tw - Tsat relation for a pool boiling process and invent a graphical method for locating the points where h is maximum and minimum. 9.15 A 2 mm diameter jet of methanol is directed normal to the center of a 1.5 cm diameter disk heater at 1 m s. How many watts can safely be supplied by the heater 9.16 Saturated water at 1 atm boils on a cm diameter platinum rod. Estimate the temperature of the rod at burnout. 9.17 Plot Tw - Tsat and the quality x as a function of position x for the conditions in Example 9.9. Set x 0 where x 0 and end the plot where the quality reaches 80 . 9.18 Plot Tw - Tsat and the quality x as a function of position in an 8 cm I.D. pipe if 0.3 kg s of water at 100 C passes through it and qw 200 000 W m2. 9.19 Use dimensional analysis to verify the form of eqn. 9.8 . 9.20 Compare the peak heat flux calculated from the data given in Problem 5.6 with the appropriate prediction. The prediction is within 11 . Problems 515 9.21 The Kandlikar correlation eqn. 9.50a can be adapted subcooled flow boiling with x 0 region B in Fig. 9.19 . Noting that qw hfb Tw - Tsat show that qw 1058 hloF Ghfg -07 Tw - Tsat 1 0 3 in subcooled flow boiling 9.47 . 9.22 Verify eqn. 9.53 by repeating the analysis following eqn. 8.47 but using the b.c. du dy y g Tg ụ. in place of du dy y g 0. Verify .