=3.1349 MJ Where: e =total heat energy, kj m =mass flow rate of air, kg/hr. hf and hi = final and enthalpy of drying and ambient air respectively, kJ/kg dry air. td = drying time, hrs = 10 hrs. The enthaphalpy (h) of air in J/kg dry air temperature T(°C)can be approximated as (Brooker el al.,1992); H = 1006.9T + w [2512131.0 + 1552.4T] (7) ………………… hi =1006.9 x 25 + 0.0018[2512131.0 + 1552.4 x 25] dry air. hf =1006.9 x 55 + 0.0014[2512131.0 + 1552.4 x 55] =88.13 kJ/kg dry air. iv- Average drying rate average drying rate, mdr, was determined from the mass of moisture to be removed by solar heat and drying time by the following equation: mdr =mw/td ------------------------------------------------------ (8) =079/10 =0.79 kg of / hr. The mass OF AIR needed for drying was calculated using equation given by sodha et al. (1987) as follows:
=3.1349 MJ Where: e =total heat energy, kj m =mass flow rate of air, kg/hr. hf and hi = final and enthalpy of drying and ambient air respectively, kJ/kg dry air. td = drying time, hrs = 10 hrs. The enthaphalpy (h) of air in J/kg dry air temperature T(°C)can be approximated as (Brooker el al.,1992); H = 1006.9T + w [2512131.0 + 1552.4T] ………………… (7) hi =1006.9 x 25 + 0.0018[2512131.0 + 1552.4 x 25] dry air. hf =1006.9 x 55 + 0.0014[2512131.0 + 1552.4 x 55] =88.13 kJ/kg dry air. iv- Average drying rate average drying rate, mdr, was determined from the mass of moisture to be removed by solar heat and drying time by the following equation: mdr =mw/td ------------------------------------------------------ (8) =079/10 =0.79 kg of / hr. The mass OF AIR needed for drying was calculated using equation given by sodha et al. (1987) as follows: