Plenary Lecture

Natural Rain – Analysis, Modeling, Simulation

Prof. Marius Otesteanu
Politehnica University of Timisoara, Romania
Dean of the Faculty of Electronics and Telecommunications
Email: marius.otesteanu@etc.upt.ro

Abstract:
NATURAL RAIN. Sprinkle equipment is used to generate water drops for fire protection, for irrigation or for functional and reliability tests of different systems designed for outdoor use. Neither of this known equipment generates patterns of drops according to natural (real) rain.
But other applications need detailed tests in atmospheric conditions, with controlled parameters, among which natural rain is one of the most important.
For such applications, a rain simulator (generator) with natural parameters, in a controlled environment, has to be developed. To achieve such equipment, next steps must be fulfilled.
RAIN ANALYSIS. In order to classify different types of rain, rain parameters have to be understood, defined and measured. Meteorological definition, limited to rain intensity (water quantity / m2 / time), is not enough to correctly classify rain types. Technical definition uses a set of measurable parameters (number of drops / m2 / time, drops size, drops velocity, etc), which allows precise classification of rain types.
The rain analysis is based on measuring methods and equipment. The paper presents rain classification criteria and, based on large amount of collected data, answers the questions:
• Is rain intensity uniformly distributed in space ? and time?
• Is the rain drops diameter constant for each type of rain ?
• What relationships are between rain intensity, drops diameter and drops velocity ?
RAIN MODELING. Several sets of parameter recording where used to select appropriate rain models. The model must match the natural rain behavior, so real rain parameters distribution where compared with computed values.
The paper presents additional requirements, imposed to a rain simulator (as desired velocity of the rain drops).
RAIN SIMULATION. Different devices (nozzles, sprinklers) where tested and selected, to simulate (generate) each type of natural rain, according to the real set of parameters.
Based on defined parameters for each type of rain and on selected rain generation devices, the design and development of a rain simulator can be started.
RAIN SIMULATOR. The paper compares different rain simulators, according to their target application and presents solutions for generating fog, drizzle, light rain, heavy rain, etc.
A complex system, based on mechanical, hydrodynamic and intelligent electronic blocks, controlled by software, is proposed to create a controlled rainy environment, able to simulate natural rain, with all its measurable parameters.

Brief Biography of the Presenter:
Prof. Marius Otesteanu obtained the Diploma of engineer – with honors, in 1978, and the Ph.D., in 1983, both in electronics, at the Politehnica University in Timisoara, Romania. From 1978 to 1982 he was with AEM Timisoara company (Electronic Measuring Equipment) as R&D engineer. Starting with 1982 he is with Politehnica University in Timisoara.
Specialized at Texas Instruments in Freising, Germany (1993, 1994) as third party consultant in digital signal processors for T.I. Visiting professor at University of South-Carolina in Columbia, U,S,A (1995-1996), at University of Central Lancashire in Preston, England (1997), at Polytechnic Institute in Oulu, Finland (1998), at Institute of Technology in Nice, France (2001), at Technical University in Ostrava, Czech Republic (2007) and at Czech Technical University in Prague (2007). Invited professor at University of Technology in Bocholt, Germany (1999, 2000) and at University of Technology in Gelsenkirchen, Germany (2006).
His scientific interest is in real time systems and in image compression. He wrote 12 books, he published 73 articles, he has 9 patents and he was involved in 18 R&D contracts.
He was organizer and chairman of the Special Session Intelligent Systems and Adaptive Control, at the WSEAS International Conference on Dynamical Systems and Control (CONTROL ’05), Venice, Italy, 2005. He was chairman of the 7th International Symposium on Electronics and Telecommunications (ETc’06), Timisoara, Romania, 2006, co-chair of the 2nd WSEAS International Conference on Dynamical Systems and Control (CONTROL '06), Bucharest, Romania, 2006, and co-chair of the 8th WSEAS International Conference on Mathematical Methods and Computational Techniques in Electrical Engineering (MMACTEE '06), Bucharest, Romania, 2006. He has co-editor of Proceedings of WSEAS International Conferences CONTROL ’05, CONTROL '06, MMACTEE '06.