Question

Consider a 30 m long pipe with a diameter of 1 cm and with a smooth interior wall surface. The pipe wall temperature is kept constant at 60 C. (a) Some liquid enters the pipe with a tempera- ture of 20° C and exits the pipe with a mix- ing cup (bulk) temperature of 57°C. Know- ing that the mass flow rate of the liquid is of 0.015 kg/s, that the liquid density is of 1000 kg/m 3, that the friction force exerted on the pipe due to the motion of fluid is equal to 0.144 N, determine the viscosity and the Prandtl number of the liquid. (b) Using the Prandtl number and viscosity found in part (a), estimate the bulk tem perature at the exit of the pipe for the same inflow temperature as in (a) but with the mass flow rate increased to 0.15 kg/s. Hint: When the flow in a pipe is fully-devel oped, the friction factor is equal to: (-dP/da) D puR/2 0.001 kg/ms, 8.88, 60°C Please show assumptions and diagram

Answer 1

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usselt Humaubon empenatanu of ppe Surke Constant h D Klu K 3. CCXJO O - 366 24.25 366 K K 887 S.S

Bipe fou unden aminea cauda dP dt 0IS2 Nustončin Lusda p uden lancanleu Canution. d P dL 32 Hu D2 3 2 x H x OJ L0-2 L03287 5.S. SE8.3