Calibration of automatic pluviometric equipment for correction of measured intensities

• Grant number: 17/09490-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: August 01, 2018
• End date: July 31, 2019
• Field of knowledge: Engineering - Civil Engineering - Hydraulic Engineering
• Principal Investigator: André Luiz de Lima Reda
• Grantee: Allan Alves Monteiro
• Host Institution: Escola de Engenharia (EE). Universidade Presbiteriana Mackenzie (UPM). Instituto Presbiteriano Mackenzie. São Paulo , SP, Brazil

Abstract

Automatic tilting type rain gauges are used increasingly in Brazil and worldwide. Your data is important for making decisions at times when heavy rain may be a risk factor; thus helping to predict floods, the need to close airports or contribute to other uses of rainfall data in the course of natural events. Due to the importance of various uses of such devices for society, it is essential that the data obtained be reliable. However, such devices are subject to errors that are not simple random uncertainties, but may be a direct function of the measured intensity itself. Therefore, knowing the relationship between the measurement error and the intensity is very important. In this study, this relation is denominated "calibration curve" of the apparatus, being inherent to each type of equipment. It may serve to correct the measurement before providing it to the user. With the objective of contributing to the increase of the state of knowledge in this area, the bench proposed here will have a dripping equipment that will simulate a desired rain intensity on the collecting entrance of the tested rain gauge. This bench will also have a test column with water up to a height (visually measurable) above the exit orifice, which may vary under control. The "calibration curve" of the column, which is the ratio of its internal water height (or "load") to the simulated intensity, will then be determined. Then the relationship between the simulated intensity by the instrument and the measurement error, which can be called the "correction curve" of the measured data or "calibration curve" (or "calibration") of the apparatus, will be determined. This will be adjusted by several experimental points (or coordinated pairs) "error x simulated intensity", obtained using the test column and the automatic rain gauge. It will be this curve that will allow the correction of each measured intensity in the field before it is supplied to the user. (AU)