Sabereh DARBANDİ, Ahmad Fakheri FARD, Ali Hosseinzadeh DALIR, Seyeed Ali SADRADDİNİ, Davood Farsady ZADEH

Hydraulic simulation of rainfall-runoff process in kamanaj watershed using diffusive model

Bu çalışmada, İran’ın Doğu Azerbaycan Bölgesinde bulunan Ajichay nehrinin bir alt havzası olan Kamanaj havzasında, iki boyutlu SV eşitlikleri kullanılarak yağışların yüzey akışına dönüşmesi simüle edilmiştir. Zaman ve mekan analizleri için yağış-yüzey akışı infiltrasyon oranlarının dikkate alınmasıyla simüle edilmiştir. SV eşitlikleri, Kesin Fark Numerik metodu ile başlangıç ve sınır koşulları saptanarak çözülmüştür. Bu amaçla, havza alanı GIS araçları yardımı ile sayısal yükseklik haritaları elde etmek amacıyla 250x250 metrekararelere bölünmüştür. İnfiltrasyon verilerini ölçmek için, en iyi uyum gösteren model olan Kostiokov infiltrasyon sistemi seçilmiş ve SV eşitlikleri uygulanmıştır. Modeli doğrulamak amacıyla, üç hidrografik kullanılmıştır. Simüle edilen ve gözlenen hidrografikler, yağış-yüzeyakışı simülasyon modelinin etkinliğini doğrulamıştır. Sunulan bu model, anlık yağışlardan oluşan yüzey akışının belirlenmesinde, havzadaki infiltrasyonun zamansal ve mekansal değişimine dikkat edilerek kullanılabilir. Bu model aynı zamanda, havzadaki boşaltımın tepe noktasını ve boşaltımın en fazla olduğu zamanı tahmin etmede kullanılabilir.

Kamanaj havzasında yağışlara bağlı yüzey akışı oluşumunun dağılma modeli yardımıyla hidrolik simülasyonu

In this research the transformation of rainfall into runoff was simulated using two dimensional SV equations in the Kamanaj watershed, a subwatershed of Ajichay river, located in East Azarbaijan Province, Iran. Rainfall-runoff was simulated based on a diffusive model by considering momentary infiltration rate for temporal and spatial analysis. SV equations were solved using explicit method of finite difference numerical technique as the initial and boundary conditions were defined. For this purpose, the watershed area was divided into a grid size of 250m×250m by the tools of GIS leading to prepare digital elevation map. Kostiokov infiltration, as the best fitted model, was selected to measure infiltration data and applied in SV equations. Three hydrographs were used to verify the model. Comparison of the simulated and observed hydrographs verificated the capability of model in simulating the rainfall-runoff. The presented model can be used for determination of runoff from momentary rainfall with consideration of temporal and spatial variation of infiltration over the watersheds.This model can also be used to forcast the peak discharge and time to peak in watershed outlet.

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