The Introduction and Usage of Hydra Model in Investigation of Storm Drain Systems Function

摘要

During the recent decades,by development of cities,destroying natural resources and reduce of plant coverage in watersheds,the amount of flood and its dangerous have a gross increase.Thus storm drain systems as a flood discharge system in rural and natural watersheds have considerable importance.According to the disastrous and sudden floods in most of our country's watersheds,necessity of study,design and investigation of system's function seem to be vital and essential.Meanwhile,the HYDRA model which was developed by FHWA in 1975 has significant importance as a simulator model of storm drain systems' function.HYDRA model is one of the sub models of the new practical software WMS which is being used to the analysis of storm drain systems' function and has high capability in simulating storm drain systems' function and also designing and optimization storm drain systems in rural or natural watersheds.The purpose of this study is to introduce this model and also the quality of simulating via HYDRA model by giving a practical and applied example,its function is also offered to engineering,researches and storm drain designers as a useful and practical model.