Hot exhaust gases are used in a shell-and-tube exchanger (1 shell and 20 tube passes) to heat 2.5 kg/s of water from 35 to 89oC. The gases, assumed to have the properties of air, enter at 200oC and leave at 93oC. The overall heat transfer coefficient is 177 W/m2K. Using the effectiveness–NTU method, calculate the area of the heat exchanger. cp = 4185 J/kgK

Aplate of dimensions 3 m x 3 m is placed 0.37 mm apart from a fixed plate. the plate requires a force of 2n to move at speed of 45 cm/s. evaluate the viscosity of the fluid in between the plates

The catalogue for a refrigerant 22, four-cylinder, hermetic compressor operating at 29 r/s. a condensing temperature of 40°c and an evaporating temperature of -4°c shows a refrigeration capacity of 115 kw. at this operating point, the motor (its efficiency is 90 percent) draws 34.5 kw. the bore of the cylinders is 87 mm and the piston stroke is 70 mm. the performance data are based on 8°c of sub-cooling of the liquid leaving the condenser. compute (a) the actual volumetric efficiency and (b) the compression efficiency.

At flow nozzle is to be installedin a 5-in type k copper tube carrying linseed oil at 77 f. a mercury manometer is to be used to measure the pressure difference across the nozzle when the expected range of the flow rate is from 700 galmin to 1000 gal/min. the manometer scale ranges from 0 to 8.0 in of mercury determine an appropriate diameter of the nozzle.