The pressure and temperature at the beginning of compression of a cold air-standard diesel cycle are 100 kpa and 300 k, respectively. at the end of the heat addition, the pressure is 7.2 mpa and the temperature is 2150 k. assume constant specific heats evaluated at 300 k. determine: (a) the compression ratio. (b) the cutoff ratio. (c) the percent thermal efficiency of the cycle. (d) the mean effective pressure, in kpa.

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