Simüle Edilmiş Yağış Desenlerinin Ölçüm Alt Alanlarında Değerlendirilmesi

Abstract

Yağış simülatörleri laboratuvar ortamlarında doğal yağışı simüle etmek için uzun yıllardır kullanılan cihazlardır. Bu laboratuvar ortamında üretilen doğal yağışın özellikle doğal değişkenliği ayrıntılı olarak incelenebildiği kontrollü laboratuvar ortamlarında, hidrolojik araştırmalar için önemli olmaktadır. Bu çalışma, bir kanallı yağış simülatörü içinde dokuz alt alana ayrılmış bir düzende yağışın temel parametreleri olan şiddet, düzgünlük ve damla çapının mekânsal değişkenliğini incelemektedir. Simülatörün 30-140 mmh-¹’lik çalışma aralığında, yağış şiddetine bağlı olarak dağılım desenlerinin nasıl değiştiğini görmek amacıyla dört farklı yoğunlukta (40, 70, 80 ve 100 mmh-¹) simülasyonlar gerçekleştirdik. Kanal alanı içerisinde I (yağış şiddeti) lokal olarak farklılıklar göstermiştir. Aynı şekilde Christiansen uniformluk katsayılarıda (CU) %69 ile %95 arasında değişmiştir. Fakat bazı alt bölgelerdeki lokal CU değerleri bu ortalamaların çok daha altında kalmıştır. D50 (medyan damla çapı), farklı yoğunluklar ve alt alanlarda 1,32 ile 1,77 mm arasında değişiklik göstermiştir. Genel olarak, yağış şiddeti arttıkça homojenlik iyileştiği fakat alan içinde hala önemli farklılıklar olduğu gözlemlenmiştir. Yağmur damlalarının boyutu düştükleri yere göre değişmektedir; genellikle alanın ortasında daha büyük damlalar gözlemlendi (A3, A4, A5). Bu sonuçlar, kanal alanı içinde aynı şiddette ve tekdüze bir yağış olduğu şeklindeki yaygın varsayımıyla çelişmekte ve simüle edilmiş yağış deneylerinin doğru şekilde yorumlanması için alt alan bazlı analizin gerekliliğini vurgulamaktadır.

Keywords

• Yağmur Simülatörü
• Christiansen Uniformluk Katsayısı
• Damla Boyut Dağılımı
• Mekânsal Değişkenlik
• Alt-Bölge Analizi

Evaluation of Simulated Rainfall Patterns in Control Plot Subsections

Abstract

Rainfall simulators have been used for many years in laboratory settings to simulate natural rainfall. This natural precipitation produced in a laboratory environment is particularly important for hydrological research in controlled laboratory environments where its natural variability can be examined in detail. This study examines the spatial variability of rainfall's fundamental parameters, intensity, uniformity, and drop diameter, in a nine-subarea arrangement within a single-channel rainfall simulator. To observe how the distribution patterns change depending on rainfall intensity within the simulator's operating range of 30-140 mmh⁻¹, we conducted simulations at four different intensities (40, 70, 80, and 100 mmh⁻¹). Within the channel area, I (rainfall intensity) showed local variations. Similarly, Christiansen's uniformity coefficients (CU) ranged from 69% to 95%. However, local CU values in some sub-regions were significantly lower than these averages. D50 (median drop diameter) varied between 1.32 and 1.77 mm for different densities and sub-areas. Generally, it was observed that homogeneity improved as rainfall intensity increased, but there were still significant differences within the area. The size of the raindrops varies depending on where they fall, with larger drops generally observed in the middle of the area (A3, A4, A5). These results contradict the common assumption of uniform rainfall intensity within the channel area and highlight the necessity of sub-area-based analysis for the accurate interpretation of simulated rainfall experiments.

Keywords

• Rainfall Simulator
• Christiansen Uniformity
• Drop-Size Distribution
• Spatial Variability
• Sub-Area Analysis

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