An acoustic water tank disdrometer

Winder, Philip Newton

Abstract

Microwave engineers and geomorphologists require rainfall data with a much greater temporal resolution and a better representation of the numbers of large raindrops than is available from current commercial instruments. This thesis describes the development of an acoustic instrument that determines rain parameters from the sound of raindrops falling into a tank of water. It is known as the acoustic water tank disdrometer (AWTD).There is a direct relationship between the kinetic energy of a raindrop and the acoustic energy generated upon impact. Rain kinetic energy flux density (KE) is estimated from measurements of the sound field in the tank and these have been compared to measurements from a co-sited commercial disdrometer.Furthermore, using an array of hydrophones it is possible to determine the drop size and impact position of each raindrop falling into the tank. Accumulating the information from many impacts allows a drop size distribution (DSD) to be calculated.Eight months of data have been collected in the eastern UK. The two methods of parameter estimation are developed and analysed to show that the acoustic instrument can produce rain KE measurements with a one-second integration times and DSDs with accurate large drop-size tails.

Citation

Winder, P. N. An acoustic water tank disdrometer. (Thesis). University of Hull. https://hull-repository.worktribe.com/output/4209840

• Thesis Type: Thesis
• Deposit Date: Aug 15, 2011
• Publicly Available Date: Feb 22, 2023
• Keywords: Engineering
• Public URL: https://hull-repository.worktribe.com/output/4209840
• Additional Information: Department of Engineering, The University of Hull
• Award Date: Aug 1, 2010