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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Journal of Computational Applied Mechanics
- نوع مقاله: Journal Article
- کلمات کلیدی: Resonant frequency,Vibration energy harvesting,Unimorph Piezoelectric vibrator,Trapezoidal V-shaped cantilever,Triangular beam
- چکیده:
- چکیده انگلیسی: The most promising method for micro scale energy scavenging is via vibration energy harvesting which converts mechanical energy to electrical energy. Using piezoelectric cantilevers is the most common method for vibration energy harvesting. Changing the shape of the cantilevers can lead to changing the generated output voltage and power. In this work vibration energy harvesting via piezoelectric resonant unimorph cantilevers is studied and new design for obtaining more efficient piezoelectric energy harvester is suggested. This study provides comprehensive analysis of the output voltage relationships and deducing a considerable precise rule of thumb for calculating resonance frequency in cantilever-type unimorph piezoelectric energy harvesters using Rayleigh method. The analytical formula, is then analyzed and verified by FEM simulation in ABAQUS. The analytical data was found to be very close to simulation data. A key finding is that among all the unimorph trapezoidal V-shaped cantilever beams with uniform thickness, the triangular tapered cantilever, can lead to highest resonance frequency and by increasing the ratio of the trapezoidal bases, the resonance frequency decreases. These new findings provide guidelines on system parameters that can be manipulated for more efficient performance in different ambient source conditions.
- انتشار مقاله: 22-07-1395
- نویسندگان: Rouhollah Hosseini,Maryam Nouri
- مشاهده
- جایگاه : پژوهشی
- مجله: Advances in Environmental Technology
- نوع مقاله: Journal Article
- کلمات کلیدی: Nitrate,Fertilizer,Phosphate,SWAT Model
- چکیده:
- چکیده انگلیسی: In the present study, the amount of nitrate and phosphate leaching from agricultural lands into the Zanjanrood River in Iran was simulated using the Soil & Water Assessment Tool (SWAT) model. The measured average monthly discharges at the Sarcham station were used to calibrate and validate the SWAT model, and the SWAT Calibration and Uncertainty Program (SWAT-CUP) model was applied to perform the uncertainty and sensitivity analyses. Three scenarios for the irrigation methods and five for the fertilizer rates were defined. The p-factor and r-factor were used for the uncertainty analysis, and two statistical indices of the coefficient of determination (R2) and Nash-Sutcliffe efficiency (NS) were utilized in the validation model. For the calibration of the monthly runoff at the basin’s outlet, the coefficients of r-factor, p-factor, R2, and NS were obtained as 0.27, 0.11, 0.83, and 0.53, respectively. The results showed that by increasing the pressurized irrigation areas, the nitrate and phosphate pollutions in the river basin were not significantly affected. With regard to fertilizer rates, by reducing the consumption of urea and phosphate fertilizers up to 50%, the amount of nitrate and phosphate leaching into the Zanjanrood River was reduced up to 16.7% and 19.2%, respectively. On the other hand, an increase of 50% in fertilizer application increased nitrate and phosphate leaching into the river by 17.2% and 17.7%, respectively. In addition, by reducing the fertilization rate and preventing unnecessary fertilization by farmers, the pollution of water resources can be largely prevented.
- انتشار مقاله: 23-04-1399
- نویسندگان: Farhad Misaghi,Mohsen Nasrabadi,Maryam Nouri
- مشاهده