The paper discusses the various types of wind tunnel tests that can be performed in the investigation of the general atmospheric conditions that exist around platforms at sea.

Emphasis is placed on an overall consideration of the purpose and expectation of model experiments in the areas of flow patterns, velocity and pressure fluctuations, and measurement of the temperature field due to hot exhaust gas plume.

An important aspect of offshore operations is the use of helicopters to transport personnel and equipment to the platforms. As an offshore platform is far from ideal for a helicopter landing site, extreme care must be taken in determining the pad’s location. Wind tunnel experiments are often necessary to aid this positioning and to demonstrate to regulatory authorities that satisfactory conditions prevail. Much can be done through the medium of flow visualisation, though attention is drawn to general guidelines that can be deduced from a consideration of the basic nature of the flow field around bluff obstructions.

For more precise information, a much more detailed representation of the platform’s geometry and the undisturbed wind structure must be employed. Evidence on the influence of such details on quantitative assessments of velocity and pressure is presented.

It is stressed that temperature measurement is another area where detailed modelling laws have to be considered, so that good representation of the plume’s position and diffusion can be achieved. It is, also, clearly necessary to predetermine the type of measure that is required. It is relevant depending on whether the experiment is concerned with surface heating, the general environment, ventilation or helicopter engine performance.