TERMA

Denmark's largest defense company has, with assistance from Kirkholm, developed a new and advanced radar antenna. Kirkholm has been involved in the entire process from start to finish and has performed the Computational Fluid Dynamic analyzes, which have been fundamentally dimensioning for the design.

With a focus on function and design, Terma has wanted to develop a new "Dual Beam High Gain  " antenna system (DBHG), which is part of systems for monitoring air traffic at airports, used in ships at sea and used to spot oil leaks from eg drilling platforms.

SUSTAINABLE AND STRATEGIC DESIGN

In many cases, radar systems have to operate in extreme weather conditions. The antenna design is inspired by advanced aircraft technology, and the system can survive wind speeds of up to 250 km / h. In comparison, it is a hurricane when the wind speed hits just 117 km/h.

Together with TERMA, Kirkholm's task in the initial phase consisted of selecting and optimizing the design to minimize the air resistance of the antenna. Including the secondary radar antenna, the purpose of which is to identify individual aircraft. The antenna system is designed in a so-called "stealth" design, which embraces a number of techniques used to make planes and ships less visible to an enemy. With its special design, the Terma antenna ensures a minimum of visibility combined with avoiding interference with the radar image.

Kirkholm engineer Jacob Fogh Knudsen, who has assisted Terma, is satisfied with the result:

"We have assisted Terma in developing a radar system that is optimized and calculated down to the smallest detail before it is sent to market. Strict requirements are set for Terma's radar systems, which must operate for at least 15-20 years in all conceivable weather conditions with a minimum of maintenance".

ADVANCED CFD SIMULATION AND ANALYSIS

In the development of the radar antenna, Kirkholm has performed the CFD simulations and analyzes (fluid mechanics), which have been crucial for the design and the subsequent strength calculations on the antenna.

"The advantage of preparing CFD analyzes early in the process is, among other things, that we can present design proposals without building expensive prototypes and conducting extensive experiments. With the analyzes, we can predict different consequences of design changes in the initial phases", says Jacob Fogh Knudsen.

After approval of the final design, Kirkholm has performed the detailed CFD analyzes of the flow around the antenna. The analyzes have subsequently been verified in wind tunnel tests on a scale of 1:2 in the USA. In addition, Kirkholm has assisted with the construction of test models, requirements specification for wind tunnel testing, construction of fixtures for the production of the antenna and preparation of drawings and documentation.