Powłoka absorbera kolektora słonecznego opis patentowy nr 202493 /

Zgłoszono 07 lutego 2007 r.Zgłoszenie ogłoszono 18 sierpnia 2008 r. BUP 17/08.O udzieleniu patentu ogłoszono 30 czerwca 2009 r. WUP 06/09.Nr zgłoszenia P 381721.Tyt. z ekranu tyt.Dostępny także w wersji drukowanej.Tryb dostępu: Internet

Novel solid – solid phase change material based on polyethylene glycol and cellulose used for temperature stabilisation

Thermal management is one of crucial issues in the development of modern electronic devices. In the recent years interest in phase change materials (PCMs) as alternative cooling possibility has increased significantly. Preliminary results concerning the research into possibility of the use of solid-solid phase change materials (S-S PCMs) for stabilisation temperature of electronic devices has been presented in the paper. Novel solid-solid phase change material based on polyethylene glycol and cellulose has been synthesized. Attempt to improve its thermal conductivity has been taken. Material has been synthesized for the purpose of stabilisation of temperature of electronic devices

Phase change materials in energy sector - applications and material requirements

Phase change materials (PCMs) have been applying in many areas. One of them is energy field. PCMs are interesting for the energy sector because their use enables thermal stabilization and storage of large amount of heat. It is major issue for safety of electronic devices, thermal control of buildings and vehicles, solar power and many others energy domains. This paper contains preliminary results of research on solid-solid phase change materials designed for thermal stabilisation of electronic devices

Reasonableness of phase change materials use for air conditioning – a short review

PCM-based systems for cooling of building spaces are a developing are a with great potential. Especially since cooling systems are becoming more popular resulting in increased demand for energy. The aim of this work is to analyse how application of phase change materials can support and improve cooling efficiency of air conditioning. Authors discuss and compare different types of PCM-based solutions

Heat transfer research on enhanced heating surfaces in pool boiling

The paper focuses on the analysis of the enhanced surfaces in such applications as boiling heat transfer. The testing measurement module with enhanced heating surfaces was used for pool boiling research. Pool boiling experiments were conducted with distilled water at atmospheric pressure in the vessel using an enhanced sample as the bottom heating surface. The samples are soldered to a copper heating block of the round cross-section .They were placed: in the fluid (saturation temperature measurement), under the sample for temperature determination. A vessel made of four flat glass panes was used for visualization. The heated surfaces in contact with the fluid differed in roughness were smooth or enhanced. This paper analyzes the effects of the microstructured heated surface on the heat transfer coefficient. The results are presented as relationships between the heat transfer coefficient and the heat flux and as boiling curves. The experimental data obtained for the two types of enhanced heated surfaces was compared with the results recorded for the smooth heated surface. The highest local values of the heat transfer coefficient were reported for the enhanced surfaces

Maximization of performance of a PCM – based thermal energy storage systems

Phase change materials (PCMs) are significant in terms of applicability for the thermal energy storage (TES). Thanks to the high thermal storage density and wide range of phase transition temperature they are promising storage mediums for a large number of applications. PCMs can be used to support efficient use of waste or excess heat. Selection of adequate material as well as design of optimal TES magazine are crucial. It is important to choose material which is characterized by suitable temperature range of phase transition, possibly high latent heat of transition, specific heat and thermal conductivity. Also important features are: ability to work properly after many operation cycles, minimum volume change and gas generation during the phase transition. It is also advantageous when PCM is non-toxic and non-corrosive, non-flammable, non-explosive, environment friendly and easy to recycle. Even the best designed PCMs would not be able to store heat efficiently if the whole magazine and its construction were not good enough. This is the reason why a lot of effort is taken to design effective TES system. The aim of this work is to analyse examples of different configurations of PCM – based thermal energy storage systems. Authors compare selected TES systems and discuss their characteristics

Transitional Phenomena on Phase Change Materials

One of the most significant problem with technology development is transferring of large heat fluxes, which requires constant heat transfer temperature (in the specified temperature range). This problem concern mainly the nuclear energetics, space technologies, military technologies and most of all electronics containing integrated circuits with very large scale of integrations. Intensive heat transfer and thermal energy storage are possible by the use of phase change materials (PCMs). In the paper there are presented preliminary results of research on the use of liquid-gas (L-G PCMs) and solid-solid phase change materials (S-S PCMs). For L-G PCMs the boiling characteristics were determined by increasing and decreasing the heat flux, which for certain sets of structural parameters of the heating surface and the physical properties of the liquid induce a variety of forms of transitional phenomena. Thermal energy storage is much more effective when using PCMs than sensible heat

Transitional Phenomena on Phase Change Materials

One of the most significant problem with technology development is transferring of large heat fluxes, which requires constant heat transfer temperature (in the specified temperature range). This problem concern mainly the nuclear energetics, space technologies, military technologies and most of all electronics containing integrated circuits with very large scale of integrations. Intensive heat transfer and thermal energy storage are possible by the use of phase change materials (PCMs). In the paper there are presented preliminary results of research on the use of liquid-gas (L-G PCMs) and solid-solid phase change materials (S-S PCMs). For L-G PCMs the boiling characteristics were determined by increasing and decreasing the heat flux, which for certain sets of structural parameters of the heating surface and the physical properties of the liquid induce a variety of forms of transitional phenomena. Thermal energy storage is much more effective when using PCMs than sensible heat