Question

In the final stages of production, a pharmaceutical is sterilized by heating it from 25 to 75C as it moves at 0.2 m/s through a straight thin-walled stainless steel tube of 12.7-mm diameter. A uniform heat flux is maintained by an electric resistance heater wrapped around the outer surface of the tube. If the tube is 10 m long, what is the required heat flux

Answer 1

The answer is "
`12682.267\ \ (W)/(m^2)`"

Step-by-step explanation:

Calculating the mass flow rate of fluid:

`m= \rho AV`

`= \rho (\pi)/(4) D^2\ V\\\\= 100 * (\pi)/(4) * (0.0127)^2* 0.2\\\\=0.0253 \ (kg)/(s)\\\\`

Calculating the amount of heat transfer.

`q =m*C_p(T_(m,0)-T_(m,i))`

`=0.0253 * 4000 (75-25)\\\\=0.0253 * 4000(50)\\\\=0.0253 * 200,000 \\\\= 5060 \ W`

Calculating the required value for heat flux:

`q`

`=(q)/(\pi DL)\\\\= (5060)/(\pi * 0.0127 * 10)\\\\= 12682.267 (W)/(m^2)\\`