Commercial building sector accounts for 8% of the total electricity consumption in India. Cooling activities (HVAC) in commercial buildings consume 55% of the total energy utilized. Consequently, CO<sub>2</su...Commercial building sector accounts for 8% of the total electricity consumption in India. Cooling activities (HVAC) in commercial buildings consume 55% of the total energy utilized. Consequently, CO<sub>2</sub> emissions from conventional buildings in India were estimated to be 98 metric tonnes of CO<sub>2</sub> per million ft<sup>2</sup> in 2014. Solar thermal air conditioning can be the solution to these demands and can contribute to about 15% to 20% of India’s total oil consumption thereby reducing the dependence on fossil fuels. Hence, the main objective of the work is to model and simulate a solar absorption cooling system for GERMI office building located in Gandhinagar, Gujarat, India, using the transient simulation software ‘TRNSYS’. Cooling load estimation and comfort conditions required for the building were determined based on ASHRAE standards. Evacuated tube collectors were selected because of its market availability, ease of manufacturing and proven technology. Single effect absorption chiller was used because of its commercial availability. The effects of storage tank volume, collector area and collector slope were also investigated for parametric optimization. The results of the simulation and parametric analysis are analyzed and presented in the paper.展开更多
Commercially available wind-turbines are optimized to operate at certain wind velocity, known as rated wind velocity. For other values of wind velocity, it has different output which is lower than the rated output of ...Commercially available wind-turbines are optimized to operate at certain wind velocity, known as rated wind velocity. For other values of wind velocity, it has different output which is lower than the rated output of the wind plant. Wind mill can be designed to provide maximum power output at different wind velocities through modification of swept area to match with the wind speed available at the moment. This can result in higher power output at all the velocities except that at rated wind speed because of limitation of generator. This results in increased utilization of generation capacity of wind mill compared to its commercially designed counterpart. A theoretical simulation has been done to prove a new concept about swept area of wind turbine blade which results in a significant increase in the power output through the year. Simulation results of power extracted through normal wind blade design and new concept are studied and compared. The findings of the study are presented in graphical and tabular form. Study establishes that there can be a significant gain in the power output with the new concept.展开更多
Organic photoconductor, pinacyanol chloride, has been studied with infrared spectroscopy because of its thermal activation energy (Ea) and band gap (Eg = 2Ea) lying in the infrared range. Particularly, pinacyanol chlo...Organic photoconductor, pinacyanol chloride, has been studied with infrared spectroscopy because of its thermal activation energy (Ea) and band gap (Eg = 2Ea) lying in the infrared range. Particularly, pinacyanol chloride and its charge transfer (CT) complexes with chloranil, DDQ, TCNQ and TCNE as organic acceptors are studied in details. The CT complexes are having neither two absorption edges like ternary complex having one donor and two acceptors nor binary type with Lorentzian or Gaussian envelopes. The forbidden gap is direct band gap except chloranil complex due to increase in molecular distance and CT interaction. There is imperfect nesting and partial screening determining the mid-IR envelope, which is qualitatively different from the envelopes in binary systems. There is inverted parabola in some range below this envelope. It is explained how infrared absorption is related with the applications of such organic photoconductors in optoelectronic devices.展开更多
文摘Commercial building sector accounts for 8% of the total electricity consumption in India. Cooling activities (HVAC) in commercial buildings consume 55% of the total energy utilized. Consequently, CO<sub>2</sub> emissions from conventional buildings in India were estimated to be 98 metric tonnes of CO<sub>2</sub> per million ft<sup>2</sup> in 2014. Solar thermal air conditioning can be the solution to these demands and can contribute to about 15% to 20% of India’s total oil consumption thereby reducing the dependence on fossil fuels. Hence, the main objective of the work is to model and simulate a solar absorption cooling system for GERMI office building located in Gandhinagar, Gujarat, India, using the transient simulation software ‘TRNSYS’. Cooling load estimation and comfort conditions required for the building were determined based on ASHRAE standards. Evacuated tube collectors were selected because of its market availability, ease of manufacturing and proven technology. Single effect absorption chiller was used because of its commercial availability. The effects of storage tank volume, collector area and collector slope were also investigated for parametric optimization. The results of the simulation and parametric analysis are analyzed and presented in the paper.
文摘Commercially available wind-turbines are optimized to operate at certain wind velocity, known as rated wind velocity. For other values of wind velocity, it has different output which is lower than the rated output of the wind plant. Wind mill can be designed to provide maximum power output at different wind velocities through modification of swept area to match with the wind speed available at the moment. This can result in higher power output at all the velocities except that at rated wind speed because of limitation of generator. This results in increased utilization of generation capacity of wind mill compared to its commercially designed counterpart. A theoretical simulation has been done to prove a new concept about swept area of wind turbine blade which results in a significant increase in the power output through the year. Simulation results of power extracted through normal wind blade design and new concept are studied and compared. The findings of the study are presented in graphical and tabular form. Study establishes that there can be a significant gain in the power output with the new concept.
文摘Organic photoconductor, pinacyanol chloride, has been studied with infrared spectroscopy because of its thermal activation energy (Ea) and band gap (Eg = 2Ea) lying in the infrared range. Particularly, pinacyanol chloride and its charge transfer (CT) complexes with chloranil, DDQ, TCNQ and TCNE as organic acceptors are studied in details. The CT complexes are having neither two absorption edges like ternary complex having one donor and two acceptors nor binary type with Lorentzian or Gaussian envelopes. The forbidden gap is direct band gap except chloranil complex due to increase in molecular distance and CT interaction. There is imperfect nesting and partial screening determining the mid-IR envelope, which is qualitatively different from the envelopes in binary systems. There is inverted parabola in some range below this envelope. It is explained how infrared absorption is related with the applications of such organic photoconductors in optoelectronic devices.