Solar Collectors Assignment -

Q1. a) For solar radiation with air mass of 1.5 calculate the total transmission (using short and long wavelengths) through:

i) 1 mm, Borofloat glass

ii) Tedlar PVF film (1 mil TTR10BG3, UV transparent)

b) For a black body at 80^oC calculate the total transmission through:

iii) 1 mm, Borofloat glass

iv) Tedlar PVF film (1 mil TTR10BG3, UV transparent)

c) Which material would you recommend for use as a domestic solar water collector cover and why?

Q2. You have been asked to calculate some performance characteristics of a new solar collector on the market. You have some of the details for it as shown below.

a) Compute the effective transmittance absorptance product (τα_eff) for normal and for 50^o incident radiation for a flat plate collector with the following characteristics

Cover: low iron glass 0.0075 m thick, extinction coefficient (K) = 3.5 m^-1.

Note: You need to estimate the diffuse reflectance.

Absorber Plate: short wavelength absorptance = 0.95 (no angular dependence).

b) Given the overall heat loss coefficient has been calculated to be 5.5W/m²K, graph the efficiency curves (η vs ?T/G) for the two angles of incidence.

c) What is the stagnation temperature for both cases with irradiance of 1100W/m² when the ambient temperature is 40^oC.

d) What type of solar cooling method would you use with this collector and why?

e) Assuming a mixed 2m high, 1m diameter thermal storage tank initially at 90^oC, with no load and no input, how long would it take to cool down to 30^oC given it is insulated with 50mm of k = 0.03W/m.K insulation and the ambient temperature is 15^oC.

Attachment:- Assignment File.rar