Sökning: "Secondary ice"

Visar resultat 1 - 5 av 21 avhandlingar innehållade orden Secondary ice.

1. 1. Secondary ice production : An empirical formulation and organization of mechanisms among simulated cloud-types

   Författare :Akash Deshmukh; MERGE: ModElling the Regional and Global Earth system; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ice; collision; ice production; ice enhancement; secondary ice; sublimation; fragmentation;

   Sammanfattning : Clouds are essential elements within Earth's atmosphere, posing a challenge for cloud-resolving models in understanding the creation of new cloud ice particles from existing ice and liquid phases. Such ice initiation determines cloud microphysical and radiative properties, influencing cloud phase, precipitation and cloud extent/properties. LÄS MER

3. 2. Mechanisms for the Influence from Ice Nucleus Aerosols on Clouds and their Indirect Effects: Cloud Modelling

   Författare :Deepak Waman; MERGE: ModElling the Regional and Global Earth system; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; clouds; Radiation; Ice Nuclei; Primary Biological Aerosol Particles; Ice particles; Secondary ice; primary ice; Aerosol particles; thunderstorm;

   Sammanfattning : The role of multiple groups of primary biological aerosol particles (PBAPs) as ice nucleating particles (INPs), and of ice formation processes such as time-dependent freezing of various INPs, and various secondary ice production(SIP) mechanisms in overall ice concentration has been evaluated in a range of cloud systems by simulating them numerically with the state-of-the-art ‘Aerosol-Cloud’ (AC) model in a 3D mesoscale domain. Also, the mechanismsof aerosol indirect effects (AIEs) arising from anthropogenic INPs, and the responses to these AIEs from time-dependent INP freezing and SIP processes are investigated in the simulated clouds. LÄS MER

4. 3. Thermophysical Properties of Aqueous Solutions Used as Secondary Working Fluids

   Författare :Åke Melinder; Björn Palm; Antero Aittomäki; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Secondary working fluids; secondary refrigerants; indirect systems; aqueous solutions; ice slurry; thermophysical properties; freezing point; density; viscosity; specific heat; thermal conductivity; Mechanical and thermal engineering; Mekanisk och termisk energiteknik;

   Sammanfattning : Secondary working fluids (secondary refrigerants, heat transfer fluids, antifreezes, brines) have long been used in various indirect re-frigeration and heat pump systems. Aqueous solutions (water solu-tions) have long been used as single phase (liquid only) secondary working fluids for cooling in supermarkets, ice rinks, heat recovery systems, heat pumps and other applications. LÄS MER

5. 4. Ice Slurry as Secondary Fluid in Refrigeration Systems : Fundamentals and Applications in Supermarkets

   Författare :Cecilia Hägg; Per Lundqvist; Mats Strömblad; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ice slurry; refrigeration; supermarket; Thermal energy engineering; Termisk energiteknik;

   Sammanfattning : This thesis summarises the work performed within the project known as ICE-COOL at the Royal Institute of Technology (KTH) on low tem-perature applications of ice slurry. The ICE-COOL project is a Euro-pean Community funded project within the 5th Framework Program. LÄS MER

7. 5. Improved Cloud Parameterization in Global Climate Model : Aerosol effects and secondary ice production mechanisms

   Författare :Arti Jadav; MERGE: ModElling the Regional and Global Earth system; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Cloud; Coud parameterization; Primary ice mechanisms; Secondary ice production; Global climate model;

   Sammanfattning : The response of clouds to the changes in climate is uncertain, and the representation of the cloud-climate feedback is a key challenge in the global circulation models (GCM) for future climate projections. Factors contributing to this uncertainty include processes that involve particles of various sizes and phases, as well as the interactions between these particles and the surrounding atmosphere. LÄS MER