A New Cloud Chamber for Studying Aerosol-Warm Cloud Interactions: Simulations and Initial Experiments

Studying aerosol-cloud interactions in a laboratory setting has traditionally been challenging without access to large-scale facilities. This work introduces an intermediate-scale cloud chamber (900L) designed for warm cloud research. Aerosol-cloud processes within the chamber are simulated using Particula, an open-source Python package for aerosol-cloud interactions. We will present the chamber design, initial experimental results, and aerosol-cloud simulations. Initial experiments were conducted to characterize the particle wall loss. In these dry experiments, different types of aerosols were used to quantify the rates of deposition to the walls using a particle size and time-dependent formula fitted with data from aerosol size measuring instruments. Sodium chloride, sucrose, dust, and smoke were all introduced separately to the chamber at low and high concentrations. These preliminary results are used to determine the wall loss rate. Additional experiments were performed at high humidity (~80-99% RH) and supersaturation. By integrating the experimental results with the Particula simulations we characterize the influence of particle properties including shape on coagulation and CCN activity.