Question

7. (25 Pts) A small business office of modern design is to be cooled by air conditioning units rated at 1.5 kW of cooling capacity. The office is designed to be occupied by a maximum of 25 individuals, and we can assume that a person would dissipate heat at a rate of 350 kJ/hr. The building is constructed with a lot of exposed glass and, as a result, heat transfer to the office on sunny days is estimated to occur at a rate of 8000 kJ/hr. If the room in the air is to be maintained at a constant temperature, determine the number of AC units that would be necessary (round up the answer to whole AC units).

Answer 1

*3600 Total heat KJ. 7. Let the number of units required = on. 1.5kW rated capacity means it would absorb the heal at res KIt haswr o 1.5*3600 kJ/hor. 30, total amount of heat absorbed per hour : =1.5 XNks generates persons : 25*960 8 750 kJ. Total heat transfer th through .: 1.5* N * 3600 = 8750 + 8000 28 N- 8750 + 8000 3600*1.5 3.102 ñ 4. so, 4 Do AC needs to be there. A from all persons the glass € 8000 kJ/her.