CE401 Water Resources Engineering Assignment 2 PDF

CE401 - Water Resources Engineering Assignment Number -2 Abstractions 1. Infiltration capacity data obtained in the flooding type infiltration test is given below: Time since start (min) 5 10 15 25...

CE401 - Water Resources Engineering Assignment Number -2 Abstractions 1. Infiltration capacity data obtained in the flooding type infiltration test is given below: Time since start (min) 5 10 15 25 45 60 75 90 115 140 Cum. Infilt. depth (cm) 1.25 2.5 3.65 5.65 7.34 8.45 9.55 10.65 12.05 13 (a) For this data plot the curve of infiltration capacity vs time. (b) Obtain the best values of the parameters in Horton’s infiltration capacity equation to represent this data. 2. The infiltration capacity in a basin is represented by Horton’s equation as f =4.5+ e-3t , where f is in cm/hr and t is in hr assuming the infiltration to take place at capacity rates in a storm of 90minutes duration, estimating the depth of infiltration in (i) the first 45minutes and (ii) second 45 minutes of storm. 3. A storm with 10cm of precipitation produced a direct runoff of 5.8cm. The duration of the rainfall was 16 hours and time distribution is given below. Estimate the φ-index of the storm. Time from start (hr) 0 2 4 6 8 10 12 14 16 Cumulative rainfall (cm) 0 0.4 1.3 2.8 5.1 6.9 8.5 9.5 10.0 4. Compute the monthly reference crop evapotranspiration using FAO modified Blaney-Criddle method? Month: July, Latitude: 300 N, Max. Temperature = 350 C, Min. Temperature = 220 C, Min. Relative Humidity = 35%, Sunshine Hours = 11.8 hrs, Wind speed = 12.6 km/hr 5. For experimental data given in following Table, fit the following infiltration models: (a) Kostiakov model, (b) Horton model. Show graphically the model fit to experimental Data. Also plot the relative erorr in model fit against time. Relative error = (observed value - computed value)/observed value Time from start Of 3 5 10 15 20 25 30 35 40 rain (min) Accumulated 0.336 0.440 0.696 0.960 1.207 1.430 1.645 1.862 2.071 infiltration (in) Time from start Of 45 50 55 60 65 70 75 80 85 rain (min) Accumulated 2.282 2.496 2.690 2.879 3.077 3.267 3.460 3.650 3.852 infiltration (in) Time from start Of 90 95 100 105 110 115 120 125 130 rain (min) Accumulated 4.040 4.212 4.408 4.593 4.787 4.967 5.153 5.352 5.521 infiltration (in) Time from start Of 135 140 rain (min) Accumulated 5.700 5.899 infiltration (in) 6. A storm with 10cm of precipitation produced a direct runoff of 5.8cm the duration of the rainfall was 16 hours and time distribution is given below. Estimate the φ-index of the storm. Time from start (hr) 0 2 4 6 8 10 12 14 16 Cumulative rainfall (cm) 0 0.4 1.3 2.8 5.1 6.9 8.5 9.5 10.0 ---ooo0ooo---