scholarly journals The choice of the method for calculating heat supply from solar radiation to determine the load on the climate system of the cabin of a mobile machine

2020 ◽  
Vol 1001 ◽  
pp. 012020
Author(s):  
V V Maslensky ◽  
Yu I Bulygin ◽  
A R Temirkanov ◽  
E V Shchekina
Keyword(s):  
Solar Radiation ◽  
Heat Supply ◽  
Climate System ◽  
Mobile Machine

scholarly journals Entropy Production and Climate Efficiency

2015 ◽  
Vol 72 (8) ◽  
pp. 3268-3280 ◽  
Author(s):  
Peter R. Bannon
Keyword(s):  
Solar Radiation ◽  
Entropy Production ◽  
Equilibrium Model ◽  
Control Volume ◽  
Heat Engine ◽  
Climate System ◽  
Work Efficiency ◽  
External Work ◽  
Radiation Fields ◽  
Earth’S Climate

Abstract Earth’s climate system is a heat engine, absorbing solar radiation at a mean input temperature Tin and emitting terrestrial radiation at a lower, mean output temperature Tout < Tin. These mean temperatures, defined as the ratio of the energy to entropy input or output, determine the Carnot efficiency of the system. The climate system, however, does no external work, and hence its work efficiency is zero. The system does produce entropy and exports it to space. The efficiency associated with this entropy production is defined for two distinct representations of the climate system. The first defines the system as the sum of the various material subsystems, with the solar and terrestrial radiation fields constituting the surroundings. The second defines the system as a control volume that includes the material and radiation systems below the top of the atmosphere. These two complementary representations are contrasted using a radiative–convective equilibrium model of the climate system. The efficiency of Earth’s climate system based on its material entropy production is estimated using the two representations.

Cogenerative PV Thermal Modules of Different Design for Autonomous Heat and Electricity Supply

2018 ◽  
pp. 86-119 ◽  
Author(s):  
Valeriy Kharchenko ◽  
Vladimir Panchenko ◽  
Pavel V. Tikhonov ◽  
Pandian Vasant
Keyword(s):  
Solar Radiation ◽  
Solar Energy ◽  
Thermal Energy ◽  
Heat Supply ◽  
Electricity Production ◽  
Electricity Supply ◽  
Well Testing ◽  
Pilot Studies ◽  
Solar Water Heating ◽  
Advantages And Disadvantages

Solar energy is used for electricity production by means of photovoltaic modules and for heat supply by means of solar water-heating collectors. In recent years, combined cogeneration photovoltaic thermal modules which work out at the same time both electricity and thermal energy began to be applied actively. The chapter includes consideration of the main types of cogenerative photovoltaic thermal modules of different design such as planar liquid devices as well as devices with concentrator of solar radiation. The advantages and disadvantages of each type are presented. Main directions for improving the efficiency of converting solar energy into thermal and electricity are offered. The description of the offered construction of the module, and also results of theoretical and pilot studies of the module is provided in full-scale conditions. Installation for such tests is described as well. Testing photovoltaic thermal modules with planar and concentrator design are presented in the chapter.

Experience and Prospects of Using Solar Energy for Heating Supply in Russia

2018 ◽  
pp. 26-60
Author(s):  
Vitaliy A. Butuzov ◽  
Vitaly V. Butuzov ◽  
Elena Bryantceva ◽  
Ilya Gnatyuk
Keyword(s):  
Solar Radiation ◽  
Solar Collector ◽  
Heat Supply ◽  
Solar Collectors ◽  
Heating Systems ◽  
Solar Heat ◽  
Diffuse Solar Radiation ◽  
Weather Stations ◽  
Heat Supply Systems ◽  
Supply Systems

Approaches to the organization of solar heat supply in Russia have a number of differences in comparison with the global experience, in particular, in the field of processing solar radiation data, designing solar collector designs, design techniques, construction and testing of solar heating systems, and the practice of creating and using solar plants. Examples of implementation of projects for creating heat supply systems in different regions of Russia are presented, from the southern (Krasnodar Territory) to the northern (Yakutia). A methodology for converting data for direct and diffuse solar radiation of NASA by taking into account the results of measurements of weather stations, which provides the possibility of their practical use, is presented. Data on the number, types, annual volumes of supplies, and names of producers of solar collectors in Russia are presented. Methodical approaches to the development of solar collectors structures based on the results of comparing the energy consumption for their production with the amount of energy produced by them during their lifetime are considered. A comparative analysis of solar design methodology in Russia and in Europe has been performed. Prospects for the construction of solar heat installations in Russia up to 2030 are considered.

Solar radiation in the cloud-free atmosphere

2021 ◽  
Author(s):  
Martin Wild
Keyword(s):  
Solar Radiation ◽  
Climate Models ◽  
Climate Model ◽  
Temporal Changes ◽  
Climate System ◽  
Radiation Budget ◽  
Radiative Effects ◽  
Free Atmosphere ◽  
Surface Solar Radiation ◽  
Radiative Fluxes

<p>The quantification of Earth’s solar radiation budget and its temporal changes is essential for the understanding of the genesis and evolution of climate on our planet. While the solar radiative fluxes in and out of the climate system can be accurately tracked and quantified from space by satellite programs such as CERES or SORCE, the disposition of solar energy within in the climate system is afflicted with larger uncertainties. A better quantification of the solar radiative fluxes not only under cloudy, but also under cloud-free conditions can help to reduce these uncertainties and is essential for example for the determination of cloud radiative effects or for the understanding of  temporal changes in the solar radiative components of the climate system.</p> <p>We combined satellite observations of Top of Atmosphere fluxes with the information contained in surface flux observations and climate models to infer the absorption of solar radiation in the atmosphere, which we estimated at 73 Wm<sup>-2</sup> globally under cloud-free conditions (Wild et al. 2019 Clim Dyn). The latest generation of climate models participating in CMIP6 is now able to reproduce this magnitude surprisingly well, whereas in previous climate model  generations the cloud-free atmosphere was typically too transparent for solar radiation, which stated a long-standing modelling issue (Wild 2020 Clim Dyn, Wild et al. 1995 JClim).</p> <p>With respect to changes in solar fluxes, there is increasing evidence that the substantial long-term decadal variations in surface solar radiation known as dimming and brightening occur not only under all-sky, but similarly also under clear-sky conditions (Manara et al. 2016 ACP, Yang et al. 2019 JClim; Wild et al. 2021 GRL). This points to aerosol radiative effects as major factor for the explanation of this phenomenon.</p>

scholarly journals Selection of a method for calculating heat gain from solar radiation to determine the load on the climate system of the cabin of a mobile car

2021 ◽  
pp. 2-7
Author(s):  
Viktor V. Maslenskiy
Keyword(s):  
Solar Radiation ◽  
Time Of Day ◽  
Climate System ◽  
Ansys Fluent ◽  
Heat Gain ◽  
Model Calculations ◽  
Correct Determination ◽  
The Heat Balance ◽  
Selection Of

Introduction. The article analyzes and selects the most rational methods for calculating the heat gain from solar radiation. The correct calculation of this component of the heat balance allows you to correctly determine the power of the projected cabin climate system, which will ensure optimal working conditions at the workplace of mobile car operators. Problem Statement. The objective of this study is to analyze and select a rational method for calculating heat gain from solar radiation for the correct determination of the thermal load on the climate system of the cabin of a mobile car. Theoretical Part. To implement the task, the most common methods for calculating solar radiation were described and analyzed in detail and the most accurate ones were recommended. Conclusions. The more labor-intensive method of V.N. Bogoslovskiy (taking into account the time of day) can be recommended for automated calculations in Excel, and the method of P.Y. Gamburg (taking into account the sides of the horizon) — for comparative estimated engineering calculations. When conducting "in-depth" model calculations and accounting for solar radiation, the ASHRAE method is explicitly suitable, which has two important advantages: it takes into account the solar factor in relation to a specific type of glazing and is adapted for automated calculations in ANSYS FLUENT.

The Earth’s Climate System

2015 ◽  
Author(s):  
Joanna D. Haigh ◽  
Peter Cargill
Keyword(s):  
Solar Radiation ◽  
Infrared Radiation ◽  
Radiative Forcing ◽  
Climate System ◽  
Atmospheric Composition ◽  
Radiative Energy ◽  
Radiation Absorption ◽  
Complex Interactions ◽  
System P ◽  
Earth’S Climate

This chapter focuses on solar radiation and its interaction with the terrestrial atmosphere in the context of the Earth's radiation budget and radiative forcing of climate, as well as its direct impact on atmospheric composition and temperature. The composition, temperature, and motion of Earth's atmosphere are determined by internal chemical and physical processes as well as by complex interactions with other parts of the climate system—notably the oceans, cryosphere and biosphere. On a global and annual average the solar energy absorbed by the Earth is balanced by thermal infrared radiation emitted to space. However, solar radiation absorption has a strong latitudinal variation, while the outgoing infrared radiation has only a weak latitudinal dependence. Thus there is a net surplus of radiative energy at low latitudes and a deficit at high latitudes.

scholarly journals SOLAR SYSTEMS FOR RESIDENTIAL BUILDINGS IN ACCORDANCE WITH OPERATING CONDITIONS OF THE REPUBLIC OF BELARUS

2017 ◽  
Vol 16 (4) ◽  
pp. 324-334
Author(s):  
M. A. Rutkowski
Keyword(s):  
Solar System ◽  
Solar Radiation ◽  
Heat Supply ◽  
Residential Buildings ◽  
Development Program ◽  
Operating Conditions ◽  
Hot Water ◽  
Solar Systems ◽  
Solar Radiation Intensity ◽  
The Republic

Solar systems are actively applied for heat supply of buildings in Europe. Usage of solar energy for heat supply of residential buildings is considered as rather efficient for the Republic of Belarus because total amount of direct and scattered solar radiation entering horizontal surface is equivalent to an average European index for the climate of Belarus. The paper analyzes an existing dependence on determination of solar system efficiency and proposes an amended formula for calculations while designing solar consumption systems and its legitimacy has been experimentally proved. A scheme of an experimental unit with explanations and a brief description for execution of experiments and main results of the completed investigations have been presented in the paper. Experiments have been carried out for solar systems with natural and forced coolant circulation. Attention has been paid to obtaining maximum possible temperature potential of the coolant during operation of the solar system within periods of high and low solar radiation intensity. Recommendations on practical application of solar systems for multi-storey residential buildings houses and mansion-type houses have been given in the paper. The paper presents technological principles of constructing “passive” solar heating devices. A comparison of traditionally applied and proposed alternative solar systems has been made for operational conditions in Belarus. The paper proposes a solar system for hot water supply of multi-storey buildings. The proposed system has found its first realization in the Republic while designing and constructing an energy-efficient demonstration 10-storey residential building in Mogilev within the framework of the UN Development Program project and Global Environment Fund “Improvement of energy efficiency for residential buildings in the Republic of Belarus”

scholarly journals Tree-Ring Based Reconstructions of Paleo-Precipitation Regimes in the Eastern Yellowstone Region

2000 ◽  
Vol 24 ◽  
pp. 144-148
Author(s):  
S. Gray ◽  
S. Jackson ◽  
K. Taylor ◽  
C. Palmer ◽  
C. Fastie
Keyword(s):  
High Resolution ◽  
Solar Radiation ◽  
Tree Ring ◽  
General Circulation ◽  
Large Scale ◽  
General Circulation Models ◽  
Climate Variation ◽  
Climate System ◽  
Precipitation Regimes ◽  
Instrumental Records

There are few other regions where the influence of climate on basic ecosystem attributes has been as well documented as the Greater Yellowstone Ecosystem (GYE). Research has shown that elk, bison, and grizzly bear populations in the GYE are tightly linked to annual climate variation (Meagher 1976, Picton 1978). Authors have shown that the distribution of vegetation types in Grand Teton and Yellowstone National Parks is influenced by the seasonality of precipitation (Despain 1987, 1990). Natural disturbances, especially fires and insect outbreaks, are also known to coincide with specific climate scenarios in this region (Knight 1987, Balling et al. 1992). Therefore, understanding how climate can vary over time is essential for the proper management of these areas (Luckman 1996). Modem instrumental records have contributed greatly to our understanding of the current GYE climate system. In particular, work by Mock (1996) and Bartlein et al. (1997) has demonstrated how local manifestations of large-scale circulation patterns produce distinct climates within the GYE. In addition, studies using modem climate records and General Circulation Models by Balling et al. (1992) and Bartlein et al. (1997) have identified trends toward increasing aridity in the GYE and the potential for these trends to continue well into the future. Late Pleistocene and Holocene (18-1 kya) climate in the GYE is known mainly from lake­sediment cores. Work by Whitlock (1993), Whitlock and Bartlein (1993), and Thompson et al. (1993) indicates that after deglaciation, increased solar radiation during summer months led to a highly seasonal climate regime. As levels of solar radiation changed through the Holocene, GYE climate became increasingly more like today until the modem regime became established around 1500-1600 AD (Whitlock 1993, Elias 1997). While existing modem and paleoecological studies reveal important aspects of the GYE climate system, there is a distinct lack of high-resolution data for most of the last millennium. Lake sediments only record climate variation at a resolution of hundreds to thousands of years, and instrumental records do not exist before the 1890s. Dendroclimatology, the study of climate using patterns of tree-ring growth (Fritts 1976) is particularly well suited to fill this gap in our knowledge of GYE climate. Tree-rings have been used successfully for climate reconstructions worldwide, offer records spanning decades to millennia, and can provide annual resolution. Therefore, we are developing a network of tree-ring sites in the western Absaroka Mountains and eastern Bighorn Basin to fill important spatial (areas east of Yellowstone NP) and temporal (high resolution for the past 700-1,000+year) gaps in our knowledge of GYE climate.

scholarly journals The calculation of the thermal mode of a room with automatic regulation of climate systems

Vestnik MGSU ◽  
2020 ◽  
pp. 585-591
Author(s):  
Oleg D. Samarin
Keyword(s):  
Heat Flow ◽  
Heat Supply ◽  
Climate System ◽  
Automatic Regulation ◽  
Thermal Mode ◽  
Indoor Climate ◽  
Indoor Temperature ◽  
Ongoing Research ◽  
Analytical Expression ◽  
Climate Systems

Introduction. The ongoing research of the indoor temperature, regulated by automatically operating climate systems, remains relevant if focused on identification of dependencies which are sufficiently accurate with regard for the majority of essential factors and represented in the engineering format. The mission of the research is to identify a dependency between indoor temperature and time in case of irregular heat supply in the context of prorated heat flow regulation by indoor climate systems. The exponential nature of this dependency serves as the research hypothesis. Materials and methods. The author has employed and analyzed the principal equations connecting the most important constituents of a heat flow in a room that has automated climate systems in the context of discontinuous changes. The author has employed a computational model of a non-steady temperature environment of a ventilated room. The proposed model is based on the solution of a system of differential equations describing heat conductivity and transfer on indoor surfaces. The author has composed and analytically solved the general differential equation describing the indoor thermal balance with regard for the climate system’s feedback. Results. The author has developed an analytical expression describing the indoor space heating rate in case of prorated temperature regulation by the climate system and irregular heat supply. The analytical expression represents an exponential function of the square root of the time span starting from the moment of a heat supply spike. The author used a residential house in Moscow to analyze the nature of indoor temperature fluctuations with and without heat regulation. Conclusions. The author has proven that an indoor temperature rate is mainly driven by the relation between the transmission coefficient of a climate system and the thermal inertia of “massive” building envelopes in case of irregular thermal exposure. The author makes the point that a simplified analytical solution is proven true by the results of the analysis performed with the help of a numerical model. It’s been identified that the ultimate value of an indoor temperature increment is determined as the relation between the heat gain value and the parameter which is proportionate to the transfer coefficient.

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