LACIS: description and transnational access
1. Introduction The Leipzig Aerosol Cloud Interaction Simulator (LACIS) is a unique facility to study aerosol cloud interactions. It was designed and built to achieve a better understanding of the mechanisms controlling aerosol and cloud interactions. With LACIS we offer a facility for the investigation of complex phase transition processes such as particle/droplet hygroscopic growth, activation, and ice nucleation. Thermodynamic parameters such as temperature, pressure, relative humidity, critical super-saturation, composition and concentrations of particles/droplets and of chemical composition of the carrier gas can be varied in ranges similar to the atmosphere. LACIS ispart of the Transnational Access of Euochamp-2.
2. Description of the research facility
LACIS consists of laminar flow tube with thermostated walls. The length of the flow tube can vary from 0.5 up to 10 m. Residence times up to 60 s and temperatures down to -40 °C are feasible. Using high precision instruments, the thermodynamic conditions in the LACIS flow tube are controlled with extremely high accuracy. LACIS can be used to investigate aerosol/cloud microphysical processes such as aerosol particle/droplet hygroscopic growth, activation, and heterogeneous ice nucleation To describe the fluid flow, heat/mass transfer and particle/droplet dynamics in LACIS, a detailed process model has been developed. It combines the computational fluid dynamics (CFD) code FLUENT with a microphysical particle/droplet dynamics model, the so-called Fine Particle Model (FPM). This model, together with the extensive expertise in the modelling of particle and droplet dynamics, is available at the facility for the interpretation of experimental results gained with LACIS. Please contact us for more information about the use of our chamber.
2.1. Technical data
The main part of LACIS is a thermostated stainless steel chamber. The high precision temperature control (accuracy in the order of 0.01 - 0.05 K) is realized by using several high precision cryostats.
A detailed list of publication can be found here.
2.4. Access to the chamber under Eurochamp TA
Access to LACIS is provided through Eurochamp-2 Transnational Access and other collaborations. LACIS offers access to various techniques and instruments for aerosol particle generation (e.g. soot, mineral dust, soluble organic and inorganic substances), physical and chemical modification (e.g. tempering, coating) and physical characterization (e.g. particle size distribution, optical properties, shape, morphology). Besides hosting instrumentation from partners for the investigation of aerosol microphysical processes in LACIS, there are also possibilities for instrument tests and intercalibration.
3. Institution in charge of the laboratory facility
The Leibniz Institute for Tropospheric Research (IfT) was founded in 1991 for the investigation of physical and chemical processes in the polluted troposphere. The institute comprises three different departments, i.e. Physics, Chemistry, and Modelling. The IfT is led by Prof. Dr. Andreas Macke.
The IfT physics department investigates meteorological und physical processes of tropospheric aerosols and clouds in the field and in the laboratory. The scientific results emerging from individual experimental studies are used to develop and validate tropospheric process models. The experimental methods include ground-based or airborne in-situ aerosol and cloud characterizations, radiation measurements, and remote sensing of meteorological data and microphysical aerosol and cloud parameters. LACIS is part of IfT's cloud group (group leader Dr. Frank Stratmann) which comprises field and laboratory investigations concerning cloud microphysical and turbulent processes.
3.1. Contact Information
Frank Stratmann, phone: +49 341 235 2862, fax: +49 341 235 2461
4. Additional Information