(4.10) 50,000 lb/h of a fluid having a density of 53 lbm/ft' and a viscosity of 1.5 cp will flow in the annulus of a double-pipe heat exchanger. The hairpins are 30 ft long with 3-in. schedule 40 outer pipe, 1.5-in. schedule 40 inner pipe, internal return bends
and 1.5-in. schedule 40 nozzles. A total of six hairpins will be used, and the maximum allowable pressure drop for the
stream is 12 psi. Determine which of the following configurations should be used in connecting the annuli of the hairpins:
• Six hairpins in series
. Two parallel banks of three hairpins each
• Three parallel banks of two hairpins each

Awall of 0.5m thickness is to be constructed from a material which has average thermal conductivity of 1.4 w/mk. the wall is to be insulated with a material having an average thermal conductivity of 0.35 w/mk so that heat loss per square meter shall not exceed 1450 w. assume inner wall surface temperature of 1200°c and outer surface temperature of the insulation to be 15°c. calculate the thickness of insulation required.

Asolid cylinder is concentric with a straight pipe. the cylinder is 0.5 m long and has an outside diameter of 8 cm. the pipe has an inside diameter of 8.5 cm. the annulus between the cylinder ad the pipe contains stationary oil. the oil has a specific gravity of 0.92 and a kinematic viscosity of 5.57 x 10-4 m2/s. most nearly, what is the force needed to move the cylinder along the pipe at a constant velocity of 1 m/s?

Agas contained within a piston-cylinder assembly e end nation about same energy states, 1 and 2, where pi 10 bar, v undergoes two processes, a and b, between the sam 0.1 m3, ui-400 kj and p2 1 bar, v2 1.0 m2, u2 200 kj: process a: process from 1 to 2 during which the pressure- volume relation is pv constant process b: constant-volume process from state 1 to a pressure of 2 bar, followed by a linear pressure-volume process to +20 0 state 2 kinetic and potential energy effects can be ignored. for each of the processes a and b, (a) sketch the process on p-v coordinates, (b) evaluate the work, in kj, and (c) evaluate process the heat transfer, in kj