A feedwater heater that supplies a boiler consists of a shell-and-tube heat exchanger with one shell pass and two tube passes. One hundred thin-walled tubes each have a diameter of 20 mm and a length (per pass) of 2 m. Under normal operating conditions water enters the tubes at 10 kg/s and 290 K and is heated by condensing saturated steam at 1 atm on the outer surface of the tubes. The convection coefficient of the saturated steam is 10,000 W/m2 K. (a) Determine the water outlet temperature. (b) With all other conditions remaining the same, but accounting for changes in the overall heat transfer coefficient, plot the water outlet temperature as a function of the water flow rate for 5 c 20 kg/s. (c) On the plot of part (b), generate two additional curves for the water outlet temperature as a function of flow rate for fouling factors of and 0.0005 m2 K/W
IT 100 (10/410/6) A. Storage & Databases a. Primary Storage (temporary storage)loses content when computer loses power. i. Volatile Storage ii. Temporary iii. Refers to random access memory (RAM) b. Secondary Storage (permanent storage) permanently saves info for future use. i. Nonvolatile storage stores programs & data as opposed to temporary RAM. ii. Characteristics 1. Media or medium what holds data 2. Capacity amount of storage held 3. Storage devices hardware that reads data 4. Access speed measures amount