Geometry: shape, size, aspect ratio and orientation Flow Type: forced, natural, laminar, turbulent, internal, external Boundary: isothermal (Tw = constant) or isoflux (q̇w = constant) Fluid Type: viscous oil, water, gases or liquid metals Properties: all properties determined at film temperature Tf = (Tw + T∞)/2 Note: ρ and ν ∝ 1/Patm ⇒ see Q12-40 density: ρ ((kg/m) specific heat: Cp (J/kg ·K) dynamic viscosity: μ, (N · s/m) kinematic viscosity: ν ≡ μ/ρ (m/s) thermal conductivity: k, (W/m ·K) thermal diffusivity: α, ≡ k/(ρ · Cp) (m/s) Prandtl number: Pr, ≡ ν/α (−−) volumetric compressibility: β, (1/K)

Convection Heat Transfer

Horizon 2020 Project “Design for Resource and Energy efficiency in CerAMic Kilns- DREAM Project (Grant No: 723641), Horizon 2020 Industrial THERMal energy recovery conversion and management (Grant No:680599) and ESPRC (Grant No: EP/P004636/1)

https://bura.brunel.ac.uk/bitstream/2438/16137/3/Fulltext.pdf

Waste Heat Recovery Technologies and Applications

The utilization of solar energy based technologies has attracted increased interest in recent times in order to satisfy the various energy demands of our society This paper presents a thorough review of the open literature on solar energy based heat and power plants In order to limit the scope of the review, only fully renewable plants with at least the production of electricity and heat/hot water for end use are considered These include solar photovoltaic and solar thermal based plants with both concentrating and non-concentrating collectors in both solar-only and solar-hybrid configurations The paper also presents a selection of case studies for the evaluation of solar energy based combined heat and power generation possibility in Denmark The considered technologies for the case studies are (1) solar photovoltaic modules, (2) solar flat plate collectors, (3) a ground source heat pump, (4) a biomass burner, and (5) an organic Rankine cycle The various cases are compared on the basis of economic profitability and environmental performance The results from the case studies indicate that it is economically and environmentally beneficial to invest in both small and large capacity solar-biomass hybrid plants for combined heat and power production in the Nordic climatic conditions The results also suggest that the configuration with an organic Rankine cycle with solar thermal collectors and a biomass burner is particularly attractive for large capacity plants

/pdf/a-review-of-solar-energy-based-heat-and-power-generation-19k9uugect.pdf

A review of solar energy based heat and power generation systems

Polygeneration as a future sustainable energy solution - A comprehensive review

A comprehensive review on coupling different types of electrolyzer to renewable energy sources

Performance Assessment of a Novel Solar and Ocean Thermal Energy Conversion Based Multigeneration System for Coastal Areas

Temperature-dependent viscosity effects in buoyancy driven flow in a porous-saturated enclosure is studied numerically, based on the general model of momentum transfer in a porous medium. The exponential form of the viscosity-temperature relation is applied. Both cases of viscosity increase and decrease versus temperature are considered. Application of the effective Rayleigh number concept and the reference temperature approach are investigated. Use of heatlines and the energy flux vectors are illustrated for a more comprehensive analysis of the problem.

/pdf/heatline-and-energy-flux-vector-visualization-of-natural-qqp4zhfnp7.pdf

Heatline and 'energy flux vector' visualization of natural convection in a porous cavity occupied by a fluid with temperature-dependent viscosity

This chapter introduces and discusses heat pump systems along with their various performance criteria in detail for various heating, ventilation, air conditioning, and refrigeration applications. Heat pump systems are classified based on heat source and heat source/sink configuration. For illustrative purposes, a basic heat pump system is analyzed both energetically and exergetically. Some common residential and industrial applications of heat pumps are discussed, and four heat pump systems are comparatively assessed through numerous case studies, including (i) air source heat pump with circulating air, (ii) air source heat pump with ventilation, (iii) submerged water source heat pump (direct expansion), and (iv) open-loop water source heat pump. Energetic and exergetic coefficient of performances of these systems are determined and compared for specific conditions.

Heat Pump Systems

The environmental effects of energy producing and consuming processes and devices are of importance to the health and living standards of people. With continuous progress in improving living standards, more energy is generally required. If produced from nonrenewable sources like fossil fuels, this leads to increasing harm to the environment. Two most common measures of performance of energy systems are energy and exergy efficiencies. Exergy efficiency provides a measure that is relative to the ideal efficiency. With exergy analysis, a better understanding of thermodynamic losses can be achieved. In this chapter, exergoenvironmental analysis, a method for analyzing energy systems and their components from a combined point of view that considers both exergy and the environment, is described and discussed. The chapter starts by describing the theory behind exergy-based environmental impact assessment of energy systems, which considers the exergy analysis, the relevant time scale and environmental parameters. This is followed by examples describing exergoenvironmental analyses of components, cycles and systems and finally with an integrated system.

1.9 Exergoenvironmental Analysis

This chapter introduces and discusses cogeneration, trigeneration, and multigeneration concepts through conceptual illustrations. It also presents various integrated and district energy systems where cogeneration, trigeneration, and multigeneration options are employed. The usefulness of exergy analysis in designing, analyzing, assessing, and improving such systems is emphasized through examples and case studies. Although energy and exergy values in general differ, exergy analysis provides more meaningful efficiencies than energy analysis and pinpoints the locations and causes of inefficiencies more accurately.

Ibrahim Dincer

Papers

Performance Assessment of a Novel Solar and Ocean Thermal Energy Conversion Based Multigeneration System for Coastal Areas

Heatline and 'energy flux vector' visualization of natural convection in a porous cavity occupied by a fluid with temperature-dependent viscosity

Heat Pump Systems

1.9 Exergoenvironmental Analysis

Cogeneration, Multigeneration, and Integrated Energy Systems