The ship rain gauge enables the measurement of precipitation on moving ships. The high-speed airflow on ships in the sea breeze causes precipitation to be almost horizontal. By measuring the amount of rainwater collected on a vertical surface, the wind speed effect can be corrected. Obviously, the local relative wind speed where the instrument is located should also be measured simultaneously. Collect precipitation through horizontal holes (arrows) and vertical collectors (shaded areas). There are five longitudinal T-shaped baffles around the vertical collector, which can prevent rainwater from flowing along the cylinder and flowing away from the leeward side.

Optional configuration:

Funnel and drainage heating device

Power supply with casing

Half universal joint

Universal joint

PC compatible counting board, including software

IMET 455

Data logger, including software

The implementation of this technology mainly involves adding a cylindrical vertical collection surface on the horizontal pipe mouth of a traditional rain gauge. Collect separately from two surfaces and measure rainfall by forming and calculating calibrated droplet sizes. The aerodynamic design of the instrument can effectively reduce the lower rain caused by the flow pattern distortion caused by the instrument itself.

The principle of measuring rainfall at a horizontal pipe mouth is the same as that of a conventional roadbed rain gauge. The surface of the vertical collector collects the liquid water content within the volume range defined by the cross-section of the rain gauge and the relative wind speed. The precipitation rate can be estimated from the atmospheric liquid water content by assuming a raindrop spectrum. It is feasible to perform empirical calibration of the instrument by collecting information from two surfaces and considering local wind speeds.

The measurement of liquid water content is independent of local airflow fluctuations. The collection amount of horizontal holes is affected by the rise and fall of air flow, depending on the distribution of raindrop spectra. This requires measuring instruments to be placed in the upper structure of the vessel, which can effectively reduce the impact of the vessel's own speed. In order to solve the problem of ship swaying at sea, the instrument is suspended and can freely sway around an axis parallel to the long axis of the ship. Ship rain gauges and optical raindrop gauges have been used several times for measuring rainwater during scientific research ship cruises, and the results have been compared. Since 1991, ship rain gauges have been operated by R. V. Meteor.

advantage:

Measuring precipitation on mobile vessels

Horizontal orifice and vertical collector

Applied to high wind speed sea surface

Can effectively prevent seawater

Standard configuration:

Funnel with horizontal collection surface

Cylindrical upper shell with vertical collection surface

Lower cylindrical shell

Internal funnel with raindrop counter

Rain gauge electronic system