الفهرس 
صفحة العنوانOnly 14 pages are availabe for public view
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Abstract
In the present study, the performance of the evacuated tube heat pipe solar collector are investigated experimentally and simulation according to Cairo-Egypt climate conditions. The experimental work conducted by using an evacuated tube heat pipe solar collector with nanofluid in indirect building heating. Simulation work is carried out by means of TRNSYS program to investigate more parameters. Different type’s water nanofluid of AL2O3/water, CeO2/water and WO3/water are performed by TRNSYS simulation at flow rate of 90 kg/h and 0.2% volume concentrations. The investigation parameters are tilt angle, AL2O3 nano-particles concentrations, mass flow rates, and water temperature difference. Validation of the simulation results with the experimental results are carried out. The experimental results show that the tilt angle 45o gives best performance characteristics of the collector which in a good agreement with TRNSYS results. At tilt angle of 45o, 90 kg/h mass flow rate, 0.2% of nanofluid concentration and 1:00 PM the working fluid temperature difference increases by 19% more than the reference fluid. The collector thermal efficiency increases with the increase of nanofluid concentrations up to 49%, 45.9%, and 43.9% a nanofluid concentration of 0.2%, 0.15%, and 0.1% respectively. At a high mass flow rate of collector working fluid of 150kg/h, the air temperature difference of heating coil increases by 6.7oC at 0.2% of nanofluid concentration. The thermal efficiency reach up to 48.6%, 46%, and 43.9% at a nanofluid concentration of 0.2%, 0.15%, and 0.1% respectively at a condition of 1:00 PM and 90kg/h. CeO2/water gives a higher performance characteristics compared to AL2O3/water, WO3/water and base water.
The study also showed the effectiveness of an integrated educational module which designed and applied to the students of fourth year grade of refrigeration and air conditioning technology at the faculty of technology and education. The results showed that there are significant differences at the level of 0.01 between the student statistical average grades in pre-application and re-application of testing and noting card for re-application by using the designed educational module. Also, there are significant difference at the level of 0.01 between the student’s statistical average grades by using educational modules in pre-application and re-application of testing for re-application.