Marine & Naval

Structural analysis of a two-axis marine radar system

Objective:

Battleships rely on radars to capture enemy and navigation data accurately. The radar system consists of two parts: the payload, which is the receiver and its sensitive electronics, and the mechanical system that carries the payload. Mechanisms are of different types: single-axis, dual-axis, rotating and swivel. They need to be extremely robust for the payload to capture accurate data. A dynamic analysis of a two-axis radar system was to be carried out to determine the dynamic response at payload locations.

Methodology:

All major structural members were modeled with solid brick elements. Spindles were idealized using 3D beam elements and other major components were modeled using 3D point mass elements. Static analysis was performed for self-weight along with the wind loads. The equipment was also studied for dynamic response under frequency response and bump test conditions. In order to keep the natural frequency above operating range, the structure was modified by adding vertical stiffeners at the cradle. It was found that stresses and deformations under frequency sweep and bump test conditions were within allowable limits.

Structural analysis of a single-axis stabilizing marine radar platform

Objective:

Battleships rely on radars to capture enemy and navigation data accurately. The radar system consists of two parts: the payload, which is the receiver along with its sensitive electronics, and the mechanical system that carries the payload. Mechanisms are of different types: single-axis, dual-axis, rotating and swivel. They need to be extremely robust for the payload to capture accurate data. A dynamic analysis of a single-axis stabilizing platform system was to be carried out to determine the dynamic response at payload locations.

Methodology:

All major structural members were modeled with solid brick elements. Ball screws were idealized using 3D beam elements and other major components were modeled using 3D point mass elements. Static analysis was performed for self-weight along with the wind loads. The equipment was also studied for dynamic response under frequency response and bump test conditions. In order to keep the natural frequency above operating range, the structure was modified by adding vertical stiffeners at the cradle. It was found that stresses and deformations under frequency sweep and bump test conditions were within allowable limits.

Structural analysis of a single-axis rotating type marine radar system

Objective:

Battleships rely on radars to capture enemy and navigation data accurately. The radar system consists of two parts: the payload, which is the receiver along with its sensitive electronics, and the mechanical system that carries the payload. Mechanisms are of different types: single-axis, dual-axis, rotating and swivel. They need to be extremely robust for the payload to capture accurate data. A dynamic analysis of a single-axis radar system was to be carried out to determine the dynamic response at payload locations.

Methodology:

All major structural members were modeled with solid brick elements. Spindles were idealized using 3D beam elements and other major components were modeled using 3D point mass elements. Static analysis was performed for self-weight along with the wind loads. The equipment was also studied for dynamic response under frequency response and bump test conditions. In order to keep the natural frequency above operating range, the structure was modified by adding vertical stiffeners at the cradle. It was found that stresses and deformations under frequency sweep and bump test conditions were within allowable limits.

Structural analysis of a marine battery tray

Objective:

Battery power plays an important role in ships and submarines. Batteries are constantly charged by generators coupled with engines to provide constant reliable power. Since the number of batteries is generally large they are placed in arrays in trays. The trays need to be designed to withstand the heavy weight of the batteries and any impact they might experience during operation. A manufacturer needed to perform a finite element static and dynamic analysis for a battery tray for various loading conditions.

Methodology:

The whole structure was idealized using shell, beam and mass elements. Static analysis has been performed for self-weight and mass of the battery. Transient dynamic analysis was carried out to analyze the battery tray for shock and impact. A frequency response analysis was carried out for constant amplitude and acceleration vs. frequency.

Static analysis results were within allowable limits. Stress and displacement values for shock and frequency analysis (for ground excitation and amplitude) were higher along transverse directions. The tray was qualified for maritime use.