Windscreen acc. to Woelfle

Woelfle developed a shield similar to the Nipher in 1934 based on wind tunnel tests.

The windscreen to Woelfle is equipped with vertically arranged circular metal lamellae. The metal lamellae are not movable and are combined conically at the base of the rain gauge. The individual slats are connected by a ring.

The windscreen ring to Woelfle consists of:
· Standpipe for the rain gauge
· Frame
· Metal fins
· Small parts for assembly

1st measuring height

The windbreak after Tretjakov is for the measuring heights:
· 100 cm
· 150 cm and
· 200 cm
 offered.
For installation, the existing foundations and set screws are used on the measuring field.
The windbreak is made of V2A 1475. The lifetime of 10 years can be guaranteed for use under average meteorological conditions. For use on islands this guarantee can not be given.

2. Construction

2.1. The ring
The windbreak after Woelfle consists of 21, 35 cm long, circularly arranged metal fins. The metal strips are trapezoidal and have a U-shape. ,

The arrangement on the circle with a diameter of 1060 mm takes place at the same distance by means of slots.
As a result, an easy interchangeability of the metal fins is guaranteed.
The slats are arranged vertically fixed. As a result, blockages of the slats are prevented at high flow rates as a function of the direction of flow and the wind speed.

3. Modifications
The aerodynamic shaping of the upper ends of the metal blade takes place at an angle of almost 90 °.
4. Maintenance
To facilitate the maintenance of the rain gauge, an element of the ring is designed hinged. The element is attached with thumbscrews and can be loosened without tools.

 5. The frame
The supports are mounted offset at 120 ° angle and run conically towards the foundation base. The supports are fixed by means of the existing pins on the foundation.
The supports and all connection components are made of V2A. The whole is also adjustable in height on the supports. This allows the system to be leveled and adapted to the requirements of the measuring point.

 6. Other
      The windscreen can be retrofitted with a bracket for anemometer to correct precipitation.