The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The main challenge for analysing system time-dependent performance of Compressed Air Energy Storage (CAES) is the complexity of the system dynamic characteristics arisen from the thermal, mechanical, chemical and electrical sub-processes. Identification of time-variant interactions between these sub-processes is essential to understand, optimise and control transient behaviour of CAES systems in practice...
A numerical model of a thermoelectric generator (TEG) is developed using the finite element method, and the convective heat-transfer coefficient and back pressure are calculated. The effect of the back pressure on the engine power loss is analyzed at different rotating speeds using GT-POWER simulation software. The optimal thermoelectric performance is analyzed considering the maximum net power output...
Most solar water heating systems (SWHS) are forced circulation systems using AC pumps. Controlled by an ON/OFF differential temperature sensing controller, the heat transfer fluid in a SWHS flows at a constant rate, and the controller consumes electricity. The controller and the sensors lead to system malfunctions, and AC pumps cycle between ON and OFF frequently under low solar irradiance. Hence,...
This paper presents an advanced mathematical model of a thermoelectric generator that includes the effect of the temperature gradient in the flow direction. The parameters of the exhaust gas from an engine may fluctuate during engine operation; thus, the influence of this fluctuation in the exhaust gas parameters on the optimal thermoelectric performance was considered with the objective of maximizing...
Research on PV/T (photovoltaic/thermal) solar collectors has been conducted for years because the collector can provide electric power and thermal energy simultaneously. A tri-functional PV/T collector is presented and studied in this paper. The collector can work in PV/water-heating mode or PV/air-heating mode for different energy demands. For two working modes, steady-state model and dynamic model...
A novel RO seawater desalination plant powered by PV (Photovoltaic) and PRO (PVROPRO) is proposed and the feasibility of two stand-alone schemes, SSRO (salinity-solar powered RO) operation and SRO (salinity powered RO) operation, are investigated. First, the stand-alone feasibility of the plant is thermodynamically analysed. In doing so, on the basis of mathematical models describing RO, PRO and the...
A new kind of expanders, called as single screw expander, has been developed by our team and applied to refrigeration systems. The present paper is to determine experimentally the refrigeration performance of a compressed air refrigeration system which is based on a single screw expander with 175 mm diameter rotor. Results indicate that the single screw expander has good refrigeration performances...
We explore the applicability of exergy analysis as an evaluation and monitoring tool for the oil and gas processing on an offshore platform. A real production day on a particular North Sea platform is analysed. A process flowsheet is simulated using measured process data. We distinguish between temperature based exergy, pressure based exergy and the mixing part of the chemical exergy. It is shown...
Minto engine is a kind of liquid piston heat engine that operates on a small temperature gradient. But there is no power formula for it yet. And its thermal efficiency is low and formula sometimes is misused. In this paper, deriving the power formula and simplifying the thermal efficiency formula of Minto engine based on energy distribution analysis will be discussed. To improve the original Minto...
As a modified building-integrated solar thermal system, building-integrated dual-function solar collector here proposed is able to provide passive space heating in cold winter, and water heating in warm seasons. In this study, evaluations were made on this modified collector system for the warm period operation under the water heating mode with natural circulation of flow. A dynamic numerical model...
In the design of solar air heaters (SAHs), channel depth is a principal variable to be fixed. In this paper, the effect of the channel depth on the energy gain of type I and type III SAHs has been investigated by computational fluid dynamics (CFD) simulations. Laminar model and k–ω turbulence model of Wilcox are used for the prediction of flow and temperature field in SAHs. Our study shows that the...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.