To cool a summer home without using a vapor compression refrigeration cycle, air is routed through a plastic pipe (k=0.15 w/m*k, d_inner=0.15m, d_outer=0.17m) that is submerged in an adjoining body of water. the water temperature is nominally at t_infinity=17 degrees celsius and has a convection coefficient of h=1500w/m^2*k is maintained at the outer surface of the pipe. if air from the home enters at t_m, i=29 degrees celsius and a volumetric flow rate of v_i=0.025 m^3/s, what pipe length, l, is needed to provide a discharge temperature of t_m, o=21 degrees celsius?

Determine the time of the day and month of the year at which the peak sensible cooling load occurs for a top floor, north-eastern corner room of an office building in durban for the following conditions: floor area: 8 x 8 x 3 m east and north walls: 115 mm face brick (outside), 20 mm air space, 115 mm ordinary brick (inside) with 15 mm plaster roof construction: suspended plasterboard ceiling, 450 mm air space, 150 mm concrete, 75mm screed, waterproofing no heat transfer across other surfaces window area 3x 1,5 m high in north wall only. ordinary glass with venetian blinds. lights and occupants : from 07: 00 to 18: 00 average light density: 25 w/m2 number of occupants : 5 seated, light office work room temperature 24°c