A modelling assessment of hydrocarbons (HC) and oxides of nitrogen (NOx) from transport sectors over Delhi

Two models IT Line Source Model (IITLS) and H1WAY-2 model have been used to estimate the concentrations of the hydrocarbons (HC) and oxides of nitrogen (NOx) due to transportation sector. An elaborate source inventory for the extrapolation of the HC and NO. emissions by vehicular transport has been developed in IITLS model. The model's predicted concentrations have been compared with the observed values at three receptors namely, Mool Chand, Ashram and AIIMS in Delhi. A statistical error analysis of the model's results and observed values has been made for evaluating the model 's performance. In the present study, it has been observed that IITLS model performs better than HIWAY-2 model.

SIMULASI MODEL DISPERSI POLUTAN KARBON MONOKSIDA DI JALAN LAYANG ( Studi Kasus Line Source Di Jalan Layang Waru, Sidoarjo)

Abstrak Polusi udara adalah masalah yang sangat penting karena berkaitan dengan penyakit akibat emisi kendaraan bermotor, yang mengandung SO2, CO2, CO, NOx, dan gas – gas lainnya. Simulasi model dispersi udara adalah salah satu cara/metode untuk mempelajari kualitas udara yang sangat dibutuhkan dalam hal ini. Pada penelitian ini dibahas tentang model matematika dari dispersi emisi gas CO dari kendaraan bermotor roda empat yang melewati jalan layang Waru, Sidoarjo. Persamaan Gauss untuk line source disusun berdasarkan mekanisme transpor polutan secara dispersi, difusi dan adveksi. Dari persamaan tersebut dapat dihitung nilai konsentrasi gas CO untuk ketinggian tertentu secara downwind. Validasi model dilakukan dengan membandingkan konsentrasi gas CO hasil perhitungan model dengan hasil pengukuran konsentrasi gas CO di lapangan. Dengan menggunakan uji R2 diperoleh nilai R2 yang mendekati satu. Karena itu model Gaussian line source digunakan sebagai model dispersi polutan CO. Model ini selanjutnya diselesaikan dan disimulasikan dengan komputer menggunakan bahasa pemrograman Fortran dan divisualisasikan menggunakan perangkat lunak Surfer. Hasil pemodelan menunjukkan bahwa model Gaussian line source dapat digunakan untuk memodelkan pola dispersi gas CO di ketinggian tertentu secara downwind di jalan layang Waru, Sidoarjo. Hasil visualisasi bulan Juni menunjukkan bahwa pola dispersi gas CO dipengaruhi oleh arah dan kecepatan angin. Konsentrasi CO pada malam hari lebih tinggi daripada pada siang hari. Dari pola dispersi CO, diusulkan agar di sekitar jalan layang terdapat ruang udara terbuka yang cukup agar bahaya yang ditimbulkan dari polutan CO yang teremisi dari sumber emisinya dapat diminimalkan. Kata Kunci : model line source, layang Waru, CO Abstract Air pollutant is the most important problem because it conducted the illness about vehicle emissions that contained SO2, CO2, CO, NOx, and other gases. The simulation of air dispersion was one model that needed to learn about air quality. In this research, we are interested at fly over Waru, Sidoarjo. The Gaussian equation for line source model was contructed with pollutant transport mechanism by dispersion, diffusion, and advection. We can get the concentration of the CO at the specific height by downwind. The model validation by compared the result of using formula and investigation at various times. By using R2test, we got it value was closed to one. The model are finished and simulated by using Fortran language programme and visualized bu using Surfer. The result of model described that the Gaussian line source model can be used to modeled the dispersion of CO at the specific height by downwind at the fly over Waru, Sidoarjo. The visualization at April showed that the dispersion of CO influenced by direction and speed of the wind. The concentration of CO at night was greater than at mid-day. We suggest that there were enough space around the fly over, suppose to minimize the effect of the pollution. Keywords: content, formatting, article.