Calculation of the Heat Energy Needed for Melting of the Ice Formed from Bounded Water in the Wood

An engineering approach for the calculation of the specific heat energy needed for melting of the ice, which is created from the freezing of hygroscopically bounded water in the wood, qbw, has been suggested. The approach, together with the equation that presents it, includes mathematical descriptions of the density of frozen wood in the hygroscopic diapason, Pw, and of the specific heat capacity of the ice formed from the bounded water in the wood, cbw for the calculation of Pw, cbw and qbw according to the suggested approach a software program has been prepared in the calculation environment of Visual Fortran. Using the program computations have been carried out for the determination ofpw, cbw and qbw, of oak, pine, beech and poplar frozen wood with initial temperature in the range from -20℃ to -2℃, at which the thawing of the ice from the bounded water is completed, and with moisture content in the hygroscopic range during wood defrosting. Based on the obtained results, a very simple and easy for use equation for the calculation of qbw depending only on the wood moisture content and on the content of non-frozen water in the wood at given initial wood temperature has been suggested.

Exploration and Application Practice of Energy Conservation Theory and Method in Steel Manufacturing Process System

This article briefly discusses the theoretical basis and overall goals of energy conservation in the steel manufacturing process system.It is proposed that in the process of implementing system energy conservation,it is necessary to fully recognize and utilize the characteristics and functional advantages of the steel manufacturing process,pay more attention to energy quality,firmly grasp the overall goal of system optimization,focus on the integrated optimization of gas,steam,and waste heat systems,and propose the idea of constructing a"steel chemi-cal gas electricity heating cooling multi generation system".Based on practice,the main principles,models,and effects of implementing systematic energy conservation in steel enterprises have been proposed.

Analyses of influence of residential buildings' space organization on heating energy consumption in Lhasa

The heating load simulation models of the residential buildings in Lhasa are established for enhancing the space organization’s adaptability to climate and radiation and improving its energy saving performance.The space organization items a e analyzed for both the existing buildings without insulation and new buildings with good insulation.The items include orientation design,south a d north balcony design,the north and south partition wall’s position design,storey height design and window-wall ratio design.Simulation results show that orientation is the key design element for energy saving design,and adverse orientation can obviouslyincrease heating energy consumption;south and north balconies can reduce winter heating energy consumption;partition walls move to the north,which means that the south room’s big depth design leads to less heating energy consumption,but the effect is not inconspicuous;smaier storey height results in less heating load.For the existing buildings,the window-wall ratio of south side has a balance point for energy saving design in the calculation condition.For the new buildings with good insulation,enlarging the south window-wal ratio can continuously reduce heating energy consumption,but the energy saving rate between models gets smaier.The heating energy consumption comparison study between the common model and optimal space design model demonstrates that the energy saving design can significantly reduce heating energy consumption

A novel method based on entransy theory for setting energy targets of heat exchanger network

A T-Q diagram based on entransy theory is applied to graphically and quantitatively describe the irreversibility of the heat transfer processes.The hot and cold composite curves can be obtained in the T-Q diagram.The entransy recovery and entransy dissipation that are affected by temperature differences can be obtained through the shaded area under the composite curves.The method for setting the energy target of the HENs in T-Q diagram based on entransy theory is proposed.A case study of the diesel oil hydrogenation unit is used to illustrate the application of the method.The results show that three different heat transfer temperature differences is 10 K,15 K and 20 K,and the entransy recovery is 5.498×10~7k W·K,5.377×10~7k W·K,5.257×10~7k W·K,respectively.And the entransy transfer efficiency is 92.29%,91.63%,90.99%.Thus,the energy-saving potential of the HENs is obtained by setting the energy target based on the entransy transfer efficiency.

Effects of sustained cold and heat stress on energy intake, growth and mitochondrial function of broiler chickens

To study the correlation of broiler chickens with energy intake, growth and mitochondrial function which exposed to sustained cold and heat stress and to find out the comfortable temperature, 288 broiler chickens（21-day with（748±26） g, 144 males and 144 females） were divided randomly into six temperature-controlled chambers. Each chamber contained six cages including eight AA broilers per cage, each cage as a repeat. After acclimation for one week（temperature, 21℃; relative humidity, 60%）, the temperature of each chamber was adjusted（finished within 1 h） respectively to 10, 14, 18, 22, 26, or 30℃（RH, 60%） for a 14-day experimental period. After treatment, gross energy intake（GEI）, metabolizable energy intake（MEI）, the ratio of MEI/BW, metabolizability, average daily gain（ADG）, the concentration of liver mitochondria protein and cytochrome c oxidase（CCO） were measured respectively. Our results confirmed that when the temperature over 26℃ for 14 days, GEI, MEI and CCO activities were decreased significantly（P〈0.05）, but the concentration of liver mitochondria protein was increased and metabolizability of broilers was not influenced（P〉0.05）. Compared with treatment for 14 days, the ratio of MEI/body weight（BW） were also decreased when the temperature over 26℃ after temperature stress for 7 days（P〈0.05）, meanwhile mitochondrial protein concentration was increased at 10℃ and CCO activity was not affected（P〉0.05）. Additionally at 22℃, the ADG reached the maximal value. When kept in uncomfortable temperatures for a long time, the ADG and CCO activities of broiler were reduced, which was accompanied by mitochondrial hyperplasia. In summary, our study focused on the performance of broilers during sustained cold and heat environmental temperatures ranging from 10 to 30℃. From the point of view of energy utilization, moreover, 22 to 26℃ is comfortable for 28–42 day s broilers. And these could provide the theoretical basis on the high efficient production.

Diffusion Mechanism of Energy Flow in Multi-heat-source Synthesis of SiC

Through the experiments and the numerical simulation of temperature field in multi-heatsource synthesis Si C furnace, in order to research the feature point in multi-heat-source synthesis furnace, the variation law of heat fl ux was studied and the multi-directional energy fl ow diffusion mechanism was revealed. The results show that, due to the shielding action between the heat-source and the superposition effect of thermal fields, the insulating effect is best in multi-heat-source synthesis furnace. The heat emission effect is good outside the common area between heat-sources, but the heat storage is poor. Compared with the synthesis furnace that heat source is parallelly arranged, the furnace of stereoscopic arrangement has a more obvious heat stacking effect and better heat preservation effect, but the air permeability of heat source connecting regions is worse. In the case with the same ingredients, the resistance to thermal diffusion and mass diffusion is higher in heat source connecting regions.

Evaluation of Energy Consumption for Heating of Industrial Building in-Situ

Because of the high energy demand required to heat a production hall, the aim of this project is to find out whether it is possible to verify the heating consuming process for heating with the standard simplified calculation method [1], especially for cold regions such as Kosice (Slovakia). The energy requirement for heating a case study industrial building was evaluated using measurements and calculations.During the winter period, energy consumption was measured in the selected industrial building according to a validation standard [2]. The building is comprised of two halls. The measurements were analyzed according to the criteria used for validating residential and public buildings, with several regression dependencies taken into account in the resulting evaluation of heating energy consumption. The mathematical dependencies of measured values in real conditions are shown in this paper. In addition, the building’s heating energy demand was calculated according to the Austrian standard [3], ?NORM EN ISO 13790, the simplified calculation method for non-residential buildings. It was investigated whether the measured values could be replicated using this calculation. It was found that the precise definition of the internal heat gains is very important.

The Effect of Spatial Structure Character of Heat Source on the Ray Path and the Evolution of Wave Energy of Meridional Wave Train

This paper studies correlations between the spatial structure character of thermal forcing and deformation and the amplitude of rays of meridional wave train. It is shown that if thermal forcing appears a meridional linear variation the rays of quasi-stationary planetary wave may propagate along oblique lines and if the meridional variability of heat source has second order term the rays show distinct deformation as a great circular route. Additionally, the inhomogeneous distribution may cause lower frequency oscillations in mid- and low-latitudes. The combination of zonal and meridional wave numbers and distributive character of heat source may form an inverse mechanism of variational trend of generized wave energy, reflecting in some degree the physical process of transition between meridional and zonal flow patterns.

The Mind-Brain Problem Bose-Einstein Statistics, Temperature, Heat, Entropy God and Other Elementary Particles

The purpose of this research is to apply the Einstein’s principle of relativity to solve the mind-brain problem and to generate all Standard Model Particle masses. Our approach is somewhat analogous to the dualistic idea of Descartes. Instead of a pineal gland, wherein the brain interacts with the mind, we propose during the developmental stages of the human fetus the tiny brain begins to communicate with the smallest structures of spacetime. This interaction occurs as the fetus brain begins to emit thermodynamic low heat energies, which are then absorbed into the smallest structures of spacetime saturating the interstices of the fetus brain. Think of these heat-energies like Morse code instructions. Since these kinds of interaction involve spacetime, with brain matter-energy, and that our main guiding principle is that of relativity, our research resulted in a general relativistic wave equation, wherein the n-valued heat-energies emitted by the brain-field-matrix Bμv, is identified as the energy momentum tensor of general relativity. The spacetime mind-matrix (Mμv) is likewise identified as the Riemannian curvature matrix. Together they form a general relativistic expression given by: Mμv +Pμv M=cBμv. Here c represents the combined general relativistic constants. By detaching the energy momentum tensor Bμv from the general relativistic wave equation, converting it to an operator, and then combining the time component with the Bose-Einstein equation, resulted in a brain temperature function capable of calculating precise heat-energies emitted by the brain during the formation of the fetus mind. As the fetus brain becomes more complex, it further organizes the mind. At some point self-aware consciousness is evoked within the spacetime mind. The same equation (relabeled to distinguish it from the mind-brain equation) can be applied to generate all Standard Model Particle masses.

Energy consumption for creep fracture of metallic materials

The energy conservation law is applied to formulate the ductile and brittle creep fracture criterion for metallic materials. The criterion contains a summary of heat and latent energies. Assuming that the heat energy is given out so it has no effect on the fracture process, the ductile creep fracture criterion is simplified. To take into account the evaluation of the damage state of materials the compressibility condition is introduced and the brittle creep fracture law is formulated.

Mathematical model of absorption and hybrid heat pump

Recovering waste heat from industrial processes is bene ficial in order to reduce the primary energy demands and heat pumps can be used to this purpose.Absorption heat pumps are energy-saving and environment-friendly because use working fluids that do not cause ozone depletion and can reduce the global warming emissions.The hybrid heat pump processes combine the conventional vapor-compression and the absorption heat pump cycles.Studies about the simulations and modeling of hybrid heat pumps are few in literature.In this research a mathematical model for single effect absorption and hybrid heat pump is carried out with Chem Cad? 6.0.1.LiBr–H_2O is used as working fluid while electrolytic NRTL and electrolytes latent heat are used as thermodynamic model due to the better results.Binary parameters of activity coef ficients are regressed from experimental vapor pressure data while default constants are used for the solubility expressions.A design of heat pumps is developed and a new modeling of generator is analyzed.The coef ficient of performance of absorption heat pump and hybrid heat pump is equal to 0.7 and 0.83 respectively.For absorption heat pump a sensitivity analysis is carried out to evaluate the effect of temperature and pressure generator,the concentration of Li–Br solution on coef ficient of performance,cooling capacity and working fluid temperature.For hybrid heat pump,the different coef ficients of performance,the primary energy ratio,the generator heat,and the compressor power are analyzed for different values of compressor proportion.Results show that comparing the two systems the hybrid pump allows to save more primary energy,costs and carbon dioxide emissions with respect to absorption heat pump with the increasing of compressor proportion parameter.Future researches should focus on the construction of this heat pumps integrated in chemical processes as a biogas plant or trigeneration systems.

Technical and Economic Aspects of Solar Space Heating in Palestine

A computer analysis of solar heating has been performed for Palestine. Results are presented for a prototype building using either fuel oil or gas under different heating loads in three climatic regions （Jordan valley, coastal, and hilly）. Cumulative cost flows are compared for the life-cycle present value technique. Optimum design magnitudes are determined for maximum life-cycle savings. The payback period for capital invested in a solar system, and total savings are found for the optimum conditions. Variations of system performance are estimated. The effects of collector slope, proportionate storage tank volume, heat-exchanger parameters, and the design load on system performance are studied. Finally the economics of solar heating in Palestine are discussed and recommendations are made for increased utilization of solar energy.

毛丝鼠体温调节发育的研究

毛丝鼠幼仔,六日龄已基本上达到恒温水平。吮乳期幼仔的静止代谢率较威体高;二日龄前,代谢率变化不符合体表面积定律;二日龄后,趋向成年恒温动物代谢类型,而符合体表面积定律。幼仔在25℃环境的热能消耗比20℃时少。

Amplified winter Arctic tropospheric warming and its link to atmospheric circulation changes

The physical cause of amplified deep Arctic tropospheric warming in winter in the Barents-Kara Seas （BKS） is examined. The authors propose that changes in the atmospheric circulation patterns are important for deep Arctic tropospheric warming in winter. It is found that the retrograde Urals blocking （UB） event concurrent with a negative North Atlantic Oscillation （NAO-） that arises from a prior negative Arctic Oscillation （AO-） is not favorable for tropospheric warming because of less water vapor over the BKS. Such UB events are related to more winter BKS sea ice associated with the negative sea surface temperature （SST） anomaly in the BKS. In contrast, a UB occurring together with a positive North Atlantic Oscillation （NAO~） shows less movement and can significantly enhance tropospheric warming over the BKS through increasing tropospheric sensible heat energy due to a persistent BKS water vapor increase. This type of quasi-stationary UB event is related to prior less BKS sea ice associated with a positive BKS SST anomaly that coexists with the North Atlantic SST tripole structure. In summary, because warm, wet and low sea-ice winters in the BKS are related to UB events with an NAO~, and depend on the winter prior sea-ice condition, the tropospheric warming is to some extent a manifestation of the sea-ice-blocking-moisture feedback in the BKS.

Performance analysis of a zeotropic mixture(R290/CO_2) for trans-critical power cycle

Low critical temperature limits the application of CO_2 trans-critical power cycle.The binary mixture of R290/CO_2has higher critical temperature.Using mixture fluid may solve the problem that subcritical CO_2 is hardly condensed by conventional cooling water.In this article,theoretical analysis is executed to study the performance of the zeotropic mixture for trans-critical power cycle using low-grade liquid heat source with temperature of200℃.The results indicated that the problem that CO_2 can't be condensed in power cycle by conventional cooling water can be solved by mixing R290 to CO_2.Variation trend of outlet temperature of thermal oil in supercritical heater with heating pressure is determined by the composition of the mixture fluid.Gliding temperature causes the maximum outlet temperature of cooling water with the increase of mass fraction of R290.There are the maximum values for cycle thermal efficiency and net power output with the increase of supercritical heating pressure.

Climate adaptive thermal characteristics of envelope of residential passive house in China

Passive house has been constructed in China on a large-scale over the past couple years for its great energy saving potential.However,research indicates that there is a significant discrepancy in energy performance for heating and cooling between passive houses in different climate zones.Therefore,this research develops a comparative analysis on the energy saving potential of passive houses with the conventional around China.A sensitivity analysis of thermal characteristics of building envelope(insulation of exterior walls and windows,and airtightness)on energy consumption is further carried out to improve the climate adaptability of passive house.Moreover,the variation of energy consumption under different heat gain intensity is also compared,to evaluate the effects of envelope thermal characteristics comprehensively.Results suggest that the decrease of exterior wall insulation leads to the greatest increase in energy consumption,especially in severe cold zone in China.However,the optimal insulation may change with the internal heat gain intensity,for instance,the decrease of insulation(from 0.4 to 1.0 W/(m^(2)·K))could reduce the energy consumption by 4.65 kW·h/(m^(2)·a)when the heat gain increases to 20 W/m^(2)for buildings in Hot Summer and Cold Winter zone in China.

Heating energy savings potential from retrofitting old apartments with an advanced double-skin façade system in cold climate

Apartments account for over 60%of total residential buildings and consume a significant portion of primary energy in South Korea.Various energy efficiency measures have been implemented for both new apartment constructions and existing apartment retrofits.Old apartment structures have poor thermal performances,resulting in a high energy consumption.The South Korean government initiated retrofitting projects to improve the energy efficiency in old apartments.Apartment owners typically replace old windows with high-performance windows;however,there is still a demand for better and more innovative retrofit methods for a highly improved energy efficiency.This paper proposes an advanced double-skin façade(DSF)system to replace existing balcony windows in old apartments.Considering the cold climate conditions of Seoul,South Korea,it mainly discusses heating energy savings.Three case models were developed:Base-Case with existing apartment,Case-1 with typical retrofitting,and Case-2 with the proposed DSF system.The EnergyPlus simulation program was used to develop simulation models for a floor radiant heating system.A typical gas boiler was selected for low-temperature radiant system modeling.The air flow network method was used to model the proposed DSF system.Five heating months,i.e.,November to March,and one representative day,i.e.,January 24,were selected for detailed analysis.The main heat loss areas consist of windows,walls,and infiltration.The results reveal that the apartment with the DSF retrofit saves 38.8%on the annual heating energy compared to the Base-Case and 35.2%compared to Case-1.

Impact of climate change on building heating energy consumption in Tianjin

This paper investigated the variation of build- ing heating energy consumption caused by global warming in Tianjin, China. Based on the hourly historical and monthly projected future （B1/A1B emissions scenarios） meteorological data, the variation of those relevant meteorological parameters was first analyzed. A TRNSYS simulation model for a reference building was introduced to investigate historical variation of office building energy consumption. The results showed that the 10-year-average heating energy consumption of 2001-2010 had reduced by 16.1% compared to that of 1961-1970. By conducting principal component analysis and regression analysis, future variation of building heating load was studied. For B1/A1B emissions scenarios, the multi-year-average heating load was found to decrease by 9.7% （18.1%）/ 10.2% （22.7%） compared to that of 1971-2010 by 2011- 2050 （2051-2100）.

对热处理炉热效率的探讨

本文分析了采用目前流行的热效率或单耗评价热处理炉能量效率的不足之处.提出了新的评估标准——真实热效率.讨论了用它评价炉子子能量效率的优点.指出真实热效率对于推动热处理节能的积极意义.

Theoretical Studies on the Structure and Detonation Properties of a Furazanbased Energetic Macrocycle Compound

Based on the full optimized molecular geometric structure at 6-311＋＋G＊＊ level,the density（ρ）,detonation velocity（D）,and detonation pressure（P） for a new furazan-based energetic macrocycle compound,hexakis[1,2,5]oxadi-azole[3,4-c：3＇,4＇-e;3＇＇,4＇＇-g：3＇＇＇,4＇＇＇-k：3＇＇＇＇,4＇＇＇＇-m：3＇＇＇＇＇,4＇＇＇＇＇-o][1,2,9,10]-tetraazacyclohexadecine,were investigated to verify its capacity as high energy density material（HEDM）. The infrared spectrum was also predicted. The heat of formation（HOF） was calculated using designed isodesmic reaction. The calculation on the bond dissociation energies（BDEs） was done and the pyrolysis mechanism of the compound was studied. The result shows that the N3–O1 bond in the ring may be the weakest one and the ring cleavage is possible to happen in thermal decomposition. The condensed phase HOF and the crystal density were also calculated for the title compound. The detonation data show that it can be considered as a potential HEDM. These results would provide basic information for the molecular design of novel high energy materials.