EXPERIMENTAL INVESTIGATION TO REDUCE HEAT INFILTRATION THROUGH ROOF STRUCTURE

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1. EXPERIMENTAL INVESTIGATION TO REDUCE HEAT INFILTRATION THROUGH ROOF STRUCTURE AND MODEL DEVELOPMENT FOR SIMULATION Presented by R. JJIJO Reg. No.: 962215407002 II year, M.E. Energy Engineering St. Xavier’s Catholic College of Engg . Project Guide Dr. R. EDWIN RAJ, M.E., Ph.D., Professor Dept. of mechanical Engineering St. Xavier’s Catholic College of Engg.

2. ENEGY SCENARIO Energy is one of the major inputs for the economic development of any country. India is 4th largest energy consuming nation in the world. Energy is an essential input in all production and many consumption activities. Energy Consumption pattern in India (%) INTRODUCTION   Domestic 22 % Industrial 45 % Commercial 8 % Agriculture 18 % Other 7 %

3. Electric energy plays a vital role in our day-to-day life activity because it is needed in almost all type of human activities. In India, growing human population, large scale industries, continuing pressure for better living standards and higher economic growth rate require more electric energy. In parallel, the consumption of electricity has also been increasing . ENERGY CONSUMPTION IN BUILDING SECTOR

4. Passive cooling Passive cooling systems use simple, low-cost techniques to provide comfort in warm climates for people and animals in buildings. Passive cooling methods use simple mechanisms and require no input of electrical energy or conventional fuels. The various methods of passive cooling can be used separately or combined, depending on site, climate, available materials and skills, and economic considerations. METHODS TO REDUCE ENERGY CONSUMPTION IN BUILDINGS

5. Reflection of Solar Heat Insulation Water Cooling Ground Cooling Evaporative Cooling PASSIVE COOLING METHODS

6. Building insulation is any object in a building used as insulation for any purpose. While the majority of insulation in buildings for thermal purposes. The term also applies to fire insulation, impact insulation, etc., Thermal insulation in buildings is an important factor to achieving thermal comfort for its occupants. Insulation reduces unwanted heat loss or gain and can decrease the energy demands of heating and cooling systems. Building insulations are two type. They are roof insulation and wall insulation. BUILDING INSULATION TECHNIQUES

7. The heat infiltration through the roof structure of the top floor in any building is about 50-70% of the total heat infiltration. which causes major discomfort to non-air conditioned buildings. So four prototype houses were built to study the heat infiltration pattern of various insulative materials. And to find an optimum methodology to mitigate heat infiltration by using low cost material. ROOF INSULATION

8. The prototype building structures for study

9. Thermocouple Data Logger Computer INSTRUMENTATION USED Photos of data logger and thermocouples

10.   Layer Layer material Dimension (mm) Density (kg/m 3 ) Specific heat (J/kg K) Thermal conductivity (W/mK) R1 Top RCC 150 2300 1130 1.63 Middle - - - - - Bottom - - - - - R2 Top White tile 25 1500 700 0.25 Middle Weathering course 150 1300 800 0.75 Bottom RCC 150 2300 1130 1.63 R3 Top White tile 25 1500 700 0.25 Middle Puf (XPS) 150 32 820 0.026 Bottom RCC 150 2300 1130 1.63 R4 Top Clay tile 25 1500 700 0.45 Middle BCS 150 1100 900 0.95 Bottom RCC 150 2300 1130 1.63 Layer configuration of each roof and its thermo-physical properties

11. Models are divided into three boundary like outside node (atmosphere side), interior nodes ,Inside node ( room side ) Apply fundamental one dimensional transient heat transfer equation for each boundary H o A(T sol p+1 -T 1 p+1 )- kA[(T 1 p+1 -T 2 p+1 )/ δx] = ρ A (δx /2)c p [ (T 1 p+1 -T 1 p ) / δx] a( i,i ) = 1+(2×bio×foo)+(2×foo); a(i,i+1) = - 2×foo; a(i,m+1 )= wt ( i )+(2×bio×foo)×T sol (n, l); Obtained Tri-diagonal matrix is solved by Numerical method using MAT LAB Result Obtained and Analyzed MODEL DEVELOPMENT FOR SIMULATION

12. Heat in =Heat out + Heat stored Outside Node with Concrete (atmosphere side)( i = 1 ) + = [ ] + Interior Nodes of Concrete ( i >1 or i <m ) Inside Node (room side) ( i =m ) + =   PROBLEM FORMULATION

13. All the above equations can be arranged in the form of tri-diagonal matrix as given below . a( i,i ) = 1+(2×bio×foo)+(2×foo); a(i,i+1 ) = - 2×foo; a(i,m+1 )= wt (i)+(2×bio×foo)×T sol (n, l ); Tri-diagonal matrix is solved by Numerical method using MAT LAB

14. Variation of roof bottom surface temperature on four day average. RESULT AND DISCUSSION

15. Heat flux of various roofs

16. Roof 1 Comparison SIMULATED AND EXPERIMENTAL VALUES COMPARISION

17. Roof 2 Comparison

18. Roof 3 Comparison

19. Roof 4 Comparison

20. Heat reduction analysis through thermal insulation is carried out for improving the thermal comfort for building without air conditioning. Similarly for air conditioned building, power consumption can be reduced, thereby the expenditure towards electricity. The following are the major findings of the investigation . This new insulation will reduce the roof bottom surface temperature by 9ºC in comparison with RCC roof without insulation. The findings shows the possibility to significantly reduce the amount of energy, thereby the cost of energy in an air-conditioned building with this type of roof insulation on the residential and commercial buildings. By adopting this new innovative thermal insulation, average heat flux entering into the room is reduced by 56 % compared to conventional RCC roof without insulation during office hours. CONCLUSION

21. THANK TOU