I am working on HEC-HMS(Hydrologic Engineering Center-Hydrologic Modeling System), HERE I HAVE DEVELOPE RAINFALL-RUNOFF MODEL FOR CERTAIN WATERSHED USING DEM AND LULC GRID MAP, AND USING BASIN MODEL, CONTROL SPECIFICATION, METEOROLOGICAL MODEL, TIME SERIES DATA,

HERE VARIABLES ARE CURVE NUMBER, LAG TIME, INITIAL ABSTRACTION, X AND Y IN THE MUSKINGUM ROUTING METHOD.

WHEN I AM VARYING THE PARAMETERS BUT NOT GETTING THE SIMULATION UP TO A SATISFACTORY LEVEL,

WHAT MAY BE THE SOLUTION?

ANY OTHER MATTER BY WHICH WE CAN GET A GOOD PERFORMANCE INDEX OF MODEL SIMULATION?