Cloud Characterization

Clouds are a very important component of the climate system because of how they affect longwave and shortwave radiation, atmospheric heat, moisture, mass transport, precipitation, and atmospheric chemistry. Clouds and feedback mechanisms associated with them are widely acknowledged as one of the key uncertainties in understanding climate and future climate prediction. Clouds are obviously also important for weather prediction. Some parameters that are important in the study of cloud physics include the cloud droplet size distribution, liquid water content (LWC), and turbulence interaction with the cloud droplets. Artium offers the PDI Flight Probe, which packages the PDI instrument into a compact system for easy external mounting, for aircraft-based studies of clouds. The probe is sufficiently heated to keep it ice-free under the most demanding conditions. A dual range PDI flight probe that essentially incorporates two PDI instruments in a single package for extended size range measurements is also available. The dual-range PDI flight probe is also available in the classical canister package.

Current threats to aviation safety include icing and encounters with high altitude ice crystals. Recent concerns with engine icing due to high altitude ice crystals which cause engine damage, and in some case flameouts, are driving the interest in measurement methods specifically suited for mixed phase conditions. Advancing the state-of-the-art in icing hazard mitigation requires a greater understanding of the fluid mechanics, thermodynamics, and materials processes involved. Specifically, there is a need for measuring liquid water content (LWC), ice water content (IWC), supercooled large drops (SLD), ice and droplet size spectrum, and ice crystal habits. Artium offers the High Speed Imaging Probe (HSI) for measuring the size, shape, and velocity of irregular particles in harsh icing environments. This probe is suitable for studying non-spherical particles such as ice crystals and mixed phase clouds that cannot be properly measured with a PDI probe alone. Besides aircraft-based study of cloud physics, the PDI Probe and the HSI Probe are also useful for wind-tunnel based icing qualification of aircrafts and engines.