(1) Tube solar systems use solar thermal collectors to convert sunlight into renewable energy for water heating and have been used worldwide for this purpose since the 19th century. (2) A common heat storing material used is paraffin compound, which takes heat from sunlight and passes it to water. (3) Based on factors like heat content, thermal diffusivity, and cost per unit volume, paraffin was determined to be the most suitable heat storing material for tube solar systems in Jordan.

1. Tubes Solar
Selection of Heat Storing Materials

2. Over View
• Tube solar is the conversions of sunlight into
renewable energy for water heating , using a
solar thermal collector solar water heating
(SWH) comprise technologies that are used
world wide increasingly

4. Solar water heating system
(SWH)
• SWH systems were discovered in 19th century
• Greece, Cyprus and Spain the leaders in the use of
SWH systems, with 30-40% of homes using them
• Here, in Jordan the cost of SWH system is about 900

5. Heat storing materials take heat from
Sun light and pass it to water

6. Selection of materials

7. Selection of heat storing material
• Function: heat storing medium
• Objective: maximum heat storing per unit cost
• Constraints: heating time ~ 10 hours
maximum temperature ~ 65 ̊
• Free variables: material choice

8. Material index calculation
• Heat content Ԛ= wˑρ Cp ΔT
Where w: thickness of layer
Cp: heat capacity
• Thermal diffusivity a= (w^2) / 2t
where t: time
• Ԛ= (2t)^2 ΔT (λ / a^0.5)
• Only λ and a are variables, then the material index (MI) =
(λ / a^0.5)

10. commentCOST/m^3MI’SMATERIALS
Expansive, it may be
used as constituent
1900 JD387.3PMMA
Suitable, available
and efficient
900JD395.3Paraffin
Not suitable, used
in construction of
heat storage walls
980 JD1000Brick
Final material choice

11. Design of tubes solar

12. paraffin compound CnH2n+2
• Paraffin hydrocarbon, also called alkane, any of the
saturated hydrocarbons having the general formula
CnH2n+2, C being a carbon atom, H a hydrogen atom,
and n an integer.
• The paraffin's are major constituents of natural gas
and petroleum.

13. Heat storage material
• A heat storage material may prepared from expanded
vermiculite (EVM) and paraffin by vacuum impregnation.
• The latent heat approximately 135.5 J/g at the melting
temperature of 48.0°C, when the paraffin content was 67%.
• The composite exhibited excellent thermal stability and has
potential application in solar thermal energy storage and solar
heating.

14. References
1- Material selection in mechanical design, Michael F.
Ashpy.
2- Review on thermal energy storage with phase
change materials and applications, Atul Sharma.
3- Internet network, Wikipedia and other sources

15. MATERIALS ENGINEERING DEPARTEMENT
MATERIALS SELECTION AND DESIGN
Name of Students:
Mohammad A. Al- Ajaramah
Suhaib A. Ibrahim Mohammad
Instructor:
Dr. Sami Massadah