For design of various types of hydraulic structures as well as for taking different flood management measures flood frequency estimates are required. Regional flood frequency analysis is carried out ...employing L-moments and soft computing techniques viz. artificial neural network (ANN) and fuzzy inference system (FIS) for the lower Godavari subzone 3(f) of India. The study area covers an areal extent of 174,201 km
2
and annual maximum peak flood data of 17 catchments ranging in size from 35 to 824 km
2
are used. The data screening is carried out employing L-moments based Discordancy measure (D
i
) and regional homogeneity is examined based on the heterogeneity measure (H). On the basis of the L-moment ratio diagram and
Z
i
dist
–statistic criteria, Pearson Type III (PE3) distribution is chosen as the suitable frequency distribution for the region. For the region under study, a relationship is developed between mean annual maximum peak flood and area of the catchment using the Levenberg-Marquardt (LM) iteration and the same is coupled with the PE3 based regional flood frequency relationship developed for estimation of floods of various frequencies for the ungauged catchments of the region. The regional flood frequency relationships developed based on L-moments and soft computing techniques are compared.
Hydrology is the science that deals with the processes governing the depletion and replenishment of water resources of the earth's land areas. The purpose of this book is to put together recent ...developments on hydrology and water resources engineering. First section covers surface water modeling and second section deals with groundwater modeling. The aim of this book is to focus attention on the management of surface water and groundwater resources. Meeting the challenges and the impact of climate change on water resources is also discussed in the book. Most chapters give insights into the interpretation of field information, development of models, the use of computational models based on analytical and numerical techniques, assessment of model performance and the use of these models for predictive purposes. It is written for the practicing professionals and students, mathematical modelers, hydrogeologists and water resources specialists.
Forecasting the ground water level fluctuations is an important requirement for planning conjunctive use in any basin. This paper reports a research study that investigates the potential of ...artificial neural network technique in forecasting the groundwater level fluctuations in an unconfined coastal aquifer in India. The most appropriate set of input variables to the model are selected through a combination of domain knowledge and statistical analysis of the available data series. Several ANN models are developed that forecasts the water level of two observation wells. The results suggest that the model predictions are reasonably accurate as evaluated by various statistical indices. An input sensitivity analysis suggested that exclusion of antecedent values of the water level time series may not help the model to capture the recharge time for the aquifer and may result in poorer performance of the models. In general, the results suggest that the ANN models are able to forecast the water levels up to 4 months in advance reasonably well. Such forecasts may be useful in conjunctive use planning of groundwater and surface water in the coastal areas that help maintain the natural water table gradient to protect seawater intrusion or water logging condition.
Accurate flood forecasting is of utmost importance in mitigating flood disasters. Flood causes severe public and economic loss especially in large river basins. In this study, multi-objective ...evolutionary neural network (MOENN) model is developed for accurate and reliable hourly water level forecasting at Naraj gauging site in Mahanadi river basin, India. The performance of the developed model is compared with adaptive neuro-fuzzy inference system (ANFIS) and bootstrap-based neural network (BNN) models. The performance of the models is compared in terms of Nash–Sutcliffe efficiency, root mean square error, mean absolute error and percentage deviation in peak (D). The performance of the models in forecasting floods is also evaluated using existing performance evaluation criterion of Central Water Commission, India as well as a multiple linear regression model. A partitioning analysis in conjunction with threshold statistics is carried out to evaluate the performance of the developed models in forecasting floods for low, medium and high water levels. It is found that the performance of MOENN and BNN models is more stable and consistent compared to ANFIS model. For longer lead times, the performance of MOENN model is found to be the best, with its performance in forecasting higher water levels being significantly better compared to ANFIS and BNN models. Overall, it is found that MOENN model has great potential to be applied in flood forecasting.
The current study employs a hierarchical adaptive network-based fuzzy inference system for flood forecasting by developing a rainfall-runoff model for the Narmada basin in India. A hybrid learning ...algorithm, which combines the least-square method and a back propagation algorithm, is used to identify the parameters of the network. A subtractive clustering algorithm is used for input space partitioning in the fuzzy and neurofuzzy models. The model architectures are trained incrementally each time step and different models are developed to predict one-step and multi-step ahead forecasts. The number of input variables is determined using a standard statistical method. An artificial neural network (ANN) model which uses an Levenberg-Marquardt (LM) backpropagation training algorithm has been developed for the same basin. The results of this study indicate that the hierarchical neurofuzzy model performs better compared to an ANN and the standard fuzzy model in estimating hydrograph characteristics, especially at longer forecast time horizons.
Experimental results on the thermal characteristics of air-water spray impingement cooling of hot metallic surface are presented and discussed in this paper. The controlling input parameters ...investigated were the combined air and water pressures, plate thickness, water flow rate, nozzle height from the target surface and initial temperature of the hot surface. The effects of these input parameters on the important thermal characteristics such as heat transfer rate, heat transfer coefficient and wetting front movement were measured and examined. Hot flat plate samples of mild steel with dimension 120 mm in length, 120 mm breadth and thickness of 4 mm, 6 mm, and 8 mm respectively were tested. The air assisted water spray was found to be an effective cooling media and method to achieve very high heat transfer rate from the surface. Higher heat transfer rate and heat transfer coefficients were obtained for the lesser i.e, 4 mm thick plates. Increase in the nozzle height reduced the heat transfer efficiency of spray cooling. At an inlet water pressure of 4 bar and air pressure of 3 bar, maximum cooling rates 670℃/s and average cooling rate of 305.23℃/s were achieved for a temperature of 850℃ of the steel plate.
Continuous over-exploitation of groundwater resources has severely curtailed the resilience of their aquifers and their ability to stabilize farming livelihoods in the face of heightened ...hydro-climatic variability. Groundwater in Punjab region is pumped from great and increasing depths, causing decline in groundwater storage which affects crop production. In this study, an investigation is carried out to evaluate the impact of climate change on groundwater storage for Joga distributary of Sirhind command area which falls under Satluj basin in India. In this analysis, observed gridded data and Regional Climate Model simulated data for mid-century and end-century period have been used for climate study. Initially, a statistical analysis is implemented to detect the trend available in precipitation and evapotranspiration data. Seasonal variation of different climate parameters shows that rainfall may increase nearly 30% by the end of the century compared to the current climatological baseline during the monsoon period. The whole basin is projected to warm significantly, with minimum temperatures rising most pronouncedly. Water Evaluation and Planning (WEAP) model has been used to estimate the groundwater storage. Different scenarios are developed using the WEAP model; analysis shows that a shift to direct seeded rice, along with improvement in irrigation efficiencies, would improve the sustainability of groundwater use. Reducing the area planted with rice by 25% almost restores the system to sustainable groundwater use. Cost analysis indicated that the cost per hectare for groundwater irrigation with direct seeded rice and a reduced area would be about 2670 Rs/ha.
This paper presents the overall performance, emission and combustion characteristics of the engine, when fuelled with biodiesel blends of Calophyllum Inophyllum methyl ester as injected fuel and ...babul wood chip derived producer gas as inducted fuel at constant injection timing (230bTDC), injection pressure (230 bar) and speed (1500 rpm). To improve overall performance, combustion and reduced emission characteristics of the engine, the combustion chamber was varied with 5 different geometries. Experimental results revealed that Toroidal re-entrant combustion chamber had higher Exhaust Gas Temperature and Brake Thermal Efficiency by 20.75% and 6.37% than that of HCC, while Brake Specific Fuel Consumption was reduced by 4.49% at optimal loading condition. However, engine overall performance of TrCC was found to be comparable with Hemi-spherical chamber and other designed combustion chambers. Similarly, comparing exhaust emissions, Oxide of Nitrogen and Carbon dioxide were on its higher side by 19.90% and 27.20% than normal HCC. On the contrary, carbon monoxide, Hydrocarbon and Smoke opacity for TrCC were found to be 76.12%, 33.71% and 38.67% lower than HCC. From the above study, it is finally concluded that converted renewable fuels with TrCC might be utilized as an alternative fuel without any exhaust related problems.
•CIME 20 showed better oil characteristics.•BTE for CIME 20-producer gas with TrCC was 6.37% higher than diesel HCC.•NOx emission for HCC-diesel was 19.9% lower than TrCC CIME20 P. gas.•CIME 20-producer gas with TrCC emits 33.71% and 38.67% less HC and smoke.•Diesel fuel savings of 80.5% for diesel-producer gas at optimal load condition.
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