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This paper presents a review of the previous studies and papers about various thermodynamic cycles working for high temperature power generation procedures, in these cycles the highest temperature is not lower than 700 K. Thermodynamic cycles that working for power generation are divided into two broad categories, thermodynamic cycle model study and working fluid analysis. Thermodynamic cycle contains the simple cycle model and the complex cycle model, emphasis has been given on the complex thermodynamic cycles due to their high thermal efficiencies. Working fluids used for high temperature thermodynamic cycles is a dense gas rather than a liquid. A suitable thermodynamic cycle is crucial for effectively power generation especially under the condition of high temperature. The main purpose is to find out the characteristics of various thermodynamic cycles when they are working in the high temperature region for power generation. As this study shows, combined cycles with both renewable and nonrenewable energies as the heat source can show good performance. [ABSTRACT FROM AUTHOR]

The theoretical study of the counter-flow dew point evaporative cooler is currently limited to the influence of different operating conditions and geometric parameters. Therefore, this paper presents an in-depth investigation on the governing factors of the dew point evaporative cooling process. A 2-D mathematical model has been developed based on the momentum, continuity, energy and species balance equations. The model was able to achieve good agreement with a maximum discrepancy of ±8.0% in predicting the transient and steady-state performance of the counter-flow dew point evaporative cooler. A new dimensionless model was produced from the general model via scaling analysis. The relevant dimensionless groups controlling the operating conditions, geometric parameters and supply air conditions were derived. We further discussed the relative importance of the physical mechanisms involved in the heat and mass transfer process. In addition, a dimensional analysis was carried out to investigate the quantitative expressions of the dimensionless time constant and product air temperature. The key findings that emerged from this study are: (1) the dominant dimensionless groups for the evaporative cooling process are Re , r , H L , δ H , T 0 ∗ and π ; and (2) the correlations for the dimensionless time constant and product air temperature have been developed and validated with data to demonstrate good accuracy. [ABSTRACT FROM AUTHOR]

Energy conversion devices undergo thermal loading during their operation as a result of inefficiencies in the energy conversion process. This will eventually lead to degradation and possible failure of the device if the heat generated is not properly managed. The ability to accurately predict the thermal behavior of such a device during the initial developmental stage is an important requirement. However, accurate predictions of critical temperature is challenging due to the variation of heat transfer parameters from one device to another. The ability to determine the model parameters is key to accurately representing the heat transfer in such a device. This paper presents the use of an inverse identification technique to estimate the model parameters of an energy conversion device designed for vehicular applications. To simulate the imperfect contact and the presence of insulating materials in the permanent magnet electric machine, thin material are introduced at the component interface of the numerical model. The proposed inverse identification method is used to estimate the equivalent thermal conductance of the thin material. In addition, the electromagnetic losses generated in the permanent magnet is also derived indirectly from the temperature measurement using the same method. With the thermal properties and input parameters of the numerical model obtained from the inverse identification method, the critical temperature of the device can be predicted more accurately. The deviation between the maximum measured and predicted winding temperature is less than 2.4%. [ABSTRACT FROM AUTHOR]

• Multi-scale and multi-domain battery modelling framework is presented. • It enables more consistent virtual representation of the electrode topology. • Coupled treatment of main and side reactions as well as heat generation phenomena. • Main and side reaction driven heat transfer cross-talk between anode and cathode. • Modelling the entire chain of mechanisms leading to outbreak of the thermal runaway. Multi-scale and multi-domain mathematical models capable of modelling main electrochemical reactions, side reactions and heat generation can reduce the time and cost of lithium-ion battery development and deployment, since these processes decisively influence performance, durability and safety of batteries. Experimental evidences clearly indicate the importance of the interplay between electric and thermal boundary conditions, cell design and applied materials, side reactions as well as safety implications of batteries, which are not yet captured to a sufficient level by simulations models. As an answer to this challenge, the paper presents an advanced multi-scale battery modelling framework that can be seamlessly integrated into multi-domain models. The key hypothesis is that nanoscopic transport phenomena and resulting heat generation decisively influence the entire chain of mechanisms that can lead to the outbreak of the thermal runaway. This is confirmed by developing a multi-scale battery modelling framework that is based on the continuous modelling approach featuring more consistent virtual representation of the electrode topology and incorporating the coupled chain of models for heat generations and side reactions. As a result, the battery modelling framework intuitively yet insightfully elucidates the entire chain of phenomena from electric and thermal boundary conditions, over cell design and properties of applied materials to solid electrolyte interphase growth, its decomposition and subsequent side reactions at the anode, cathode and the electrolyte that lead to the thermal runaway. One of key results comprises multi-level main and side reaction driven heat transfer cross-talk between the anode and the cathode. Therefore, the presented advanced multi-scale battery modelling framework represents a contribution to the advanced virtual development of batteries thereby contributing to tailoring battery design to a specific application. [ABSTRACT FROM AUTHOR]