摘要
In this paper, a spreadsheet modeling is introduced as a tool for studying fully distributed real-world engineering problems. The merits of using the spreadsheet are the following: its simplicity, the spreadsheet is very well known to many researchers and engineers; it performs fast calculations; it has a user-friendly graphic interface; and it can also provide animated graphs. These merits provide engineers and scientists with a flexible tool to tackle environmental problems and quickly performing solution scenarios to their problems. A real-world case study has been presented to illustrate the application of such spreadsheet models. The groundwater level rise in Jeddah city is one of the problems that Jeddah city are facing. The reasons of groundwater level rise in Jeddah are the following: the leakage from septic tanks, leakage from freshwater pipe networks, landscape irrigation, annual rainfall, flash floods from eastern wadis, etc. These sources have been complied with a regional groundwater flow model (the general form of the partial differential equation for steady groundwater flow in a heterogeneous, unconfined aquifer with a fully distributed recharge, evaporation and pumping rates, and with a variable aquifer bottom elevation), discritized with a finite difference method, then formulated on a spreadsheet, and solved with the built-in macro-solver on the Excel software. The spreadsheet model has been tested and compared with analytical solution. The model has also been calibrated with observations, and the correlation coefficient was 0.96 for the hydraulic head data. The results have been displayed graphically in one, two, and three dimensions. Various scenarios have been investigated to show solutions of the problem. The results have shown that the spreadsheet modeling is a powerful, flexible, and a user-friendly tool in modeling fully distributed real-world engineering problems. Results can be transferred from spreadsheet to GIS software to present results over satellite images or base maps. Analysis of various solution scenarios can be done efficiently, and one can get quick answers to the decision makers at a preliminary stage of a project before going to a sophisticated modeling approach with specialized software.