K12AE3 Exam paper 2015-16 UPDATED V2.pdf Answer ALL parts of this.

K12AE3 Exam paper 2015-16 UPDATED V2.pdf Answer ALL parts of this.

K12AE3 Exam paper 2015-16 UPDATED V2.pdfAnswer ALL parts of this question.

 

The Shard is a glass-clad pyramidal tower with 72 floors located adjacent to the river Thames. The Shard’s peak sensible and latent cooling loads are 8MW, and 1618kW, respectively, which occur when the outside dry bulb air temperature is 35 C with 70% saturation. The fresh air requirement is 55,000l/s.

The building’s air conditioning system employs recirculation to save energy. It supplies air with a dry bulb temperature of 12 C and 90% saturation to maintain a dry bulb indoor air temperature of 24 C. Use a psychrometric chart and hand calculations to answer these questions:

1. (a)  Show that the volume flow rate of air supplied to the building at peak
   cooling load is 550m3/s and the proportion of fresh air is 10%.
2. (b)  Mark the outdoor, supply, room and mixing points on the psychrometric
   chart by using an O, R, and M, respectively, and connect them. Identify
   the moisture content, dry bulb temperature, wet bulb temperature, and
   specific enthalpy of the mixed air.

K12AE3 Exam paper 2015-16 UPDATED V2.pdf

1. (c)  If the change in specific enthalpy from the mixing to the supply points is 20kJ/kg, estimate the annual running costs and carbon emissions of the chiller to the nearest pound and tonne of CO₂e, respectively. Assume that the cooling plant has a C.O.P of 2.5 and runs for 470 hours per year, and electricity has a price of 10p/kWh and carbon emissions of 0.2kgCO₂e/kWh.

K12AE3 Exam paper 2015-16 UPDATED V2.pdf

(d) Discuss methods of reducing peak heating and cooling loads in buildings that contain a lot of glass in their vertical facades. Consider technological, material, and architectural measures.

K12AE3 Exam paper 2015-16 UPDATED V2.pdf