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Thermodynamic models and its application for open feedwater heaters under transient conditions Xiyan Guo1,a, Aiyuan Li1, Hui Xu2, Peng Fu1 1School of Energy Power and Mechanical Engineering, North China Electric Power University, China 2School of Control and Computer Engineering, North China Electric Power University, China ag_x_y@163.com Keywords: Thermodynamic models; energy distribution; surface heaters; transient conditions Abstract: The aim of this paper is to find the energy distribution principle of open feedwater heaters under transient conditions.
The major factor is the exergy stored in exothermic fluid.
Depending on the fluid properties of the heater, it consists of vapor-cooler section, vapor-condensate section and drain-cooler section.
We can see from table that the error caused by the exergy stored in fluid is the largest and the second is the exergy stored in metal.The primary factors of exergy stored in fluid are temperature, pressure and flow rate.
Refrigeration & Air-condition，2002, 3: 5-8 (in Chinese) [9] Jingyan Xing, Hai-qing Wang．Factors of affecting exergetic efficiency of heat exchanger and their functions in thermoeconomic analysis[J].

The size of HVOF particles is from 140 to 325mm and too small power will produce burning and flying upward so that it can affect the coating performance and the efficiency of coating. 3.1 The preparation technology of nano-particles There are three methods to prepare nano-particles.
And the other is mechanical grinding method.
The automatic control method is suitable for field operation in workshop and it is easy to noise elimination because the mechanical arm controlled by computer is used to spray.
However, automatic spraying system needs mechanical arms controlled by computers so that the equipment is complex and large.
In addition, the high price of nano-WC alloy powder is one of the main factor affect the application.

Introduction The grain boundary (GB) is the area where numerous phase transformations easily occur, leading to dramatic changes on the mechanical and physical properties of polycrystalline materials [1,2].
The presence of premelting significantly affects the strength and fracture properties of polycrystalline materials.
Heating rate is an important factor of the GB premelting.
Kuebler, The influence of the grain boundary phase on the mechanical properties of Si3N4-MoSi2 composites, Acta Mater. 55(2007) 2875-84
Baretzky,  Grain boundary phase transitions and their influence on properties of polycrystals, Interface Sci. 12(2004) 147-155

Mechanical Properties.
Mechanical Properties.
These points confirm that microcrystalline cellulose solution can reinforce located at outsides of cuboid shaped samples to make the strengthened samples bear higher compressive stress and perform stronger mechanical property.
Notably, microcrystalline cellulose concentration in the initial solution was an important factor which affects samples mechanical properties.
In conclusion, the skeleton strengthened of BCAs was achieved, which provided a simple and feasible way to obtain SBCAs with excellent mechanical properties for extensive applications.

The mechanical properties of the bar cast by these was continuous casting process was very fine.
In the present study, properties of the rheo-casting by UEDTRC to cast bar was investigated.
Flow rate of the melt affected the cooling of the melt.
The fall height of the melt affected the heat transfer between the melt and the cooling slope.
The falling height of the melt was important factor to cool the melt.

Composite manufacturing processes and their effects to the material properties are cited.
The achievement of this kind of model is difficult since damage factors could be adjusted for FE results to give a valid solution without experimental correlation.
First of all, through-thickness properties need to be obtained in order to constitute input data of the numerical models, in addition to standard in-plane properties.
Woven fabric plies properties are used.
Effect of cure cycle heat transfer rates on the physical and mechanical properties of an epoxy matrix composite.

Operation is easy to damage the digester wall, for large and medium-sized straw biogas refueling mechanical pressing of the R & D.
The role of research institutions, to attract users to actively participate in the farmers to mobilize all positive factors in the community to participate in this work, to speed up the process of using straw gas.
Straw unified gas engineering services Biogas plants for straw need professional centralized management, unified service, strengthen the straw gas service property management station construction, property management station to configure the transport machinery, mechanical access to materials, maintenance tools, and security detection equipment and other specialized equipment, training of professional staff and centralized gas users to conduct straw supply of raw materials, access to materials services, maintenance and safety checks, etc., so that straw biogas production process management standardization, to improve the effectiveness of straw gas use, quality and safety.
Local governments should address the development of local characteristics, to develop short-and long-term development plan, to avoid the excessive pursuit of short-term effects, resulting in unnecessary waste, affecting the gas industry's long-term development, to be targeted to increase investment, support and guide correctly, by administrative promotion, policy support, increase publicity and create an atmosphere to promote the comprehensive utilization of straw gas to carry out solid work.
Mechanical slurry residue discharge car security [J].Technology Innovation Review, 2011 (03): 49 [10] Lv Jianqiang, etc.

Results show that the varieties of chlorides have great impacts on the chloride binding ability, mechanical properties and microstructure of cement pastes at different temperatures.
Introduction Chloride attack is the most important factor affecting the durability of concrete structures in the marine environment[1,2].
Besides cement types, factors such as temperature and chloride types have great impact on the erosion and destruction process as well[8-12].
Study on the influence factors of chloride binding in sea sand concrete[J].

In this paper, we propose a nonlinear control technique which is based on Flatness system properties for the voltage loop and a nonlinear control based on sliding-mode for the current loop.
The emissions of gases from the combustion not only cause air pollution, but affects human and leads to global warming.
To control this converter, instead of using a linear multiple-loop feedback control technique [3], we propose nonlinear control technique, which is based on Flatness system properties [4,5] for the voltage loop and a nonlinear control based on sliding-mode [6,7] for the current loop.
Fig 1. 2-Phase interleaved boost converter CONVERTER MODEL VIA FLATNESS SYSTEM Since 1995, Flatness system has been introduced in by Fliess [4]; its properties have been contributed to many applications even in mechanical or electrical domains [4].
The main advantage of the system controlled using flatness system properties is that the desired trajectories of the flat outputs can be planned even in transient state.

In various heat loss, heat loss Q5 and ash physical heat loss Q6 amount is small, are related to the boiler equipment material quality,heat preservation,boiler load and fuel property,etc, respectively.has little to do with running adjustment [2].
So the temperature of furnace temperature is mainly affected by smoke loss Q2 and incomplete combustion loss Q3+Q4.
And smoke heat loss is the larger one, generally about 6% ~ 12%, exhaust temperature and exhaust smoke volume are the main influencing factors, the more excess air, the more exhaust smoke volume is, the greater the smoke losses is. solid incomplete combustion loss is mainly due to that the ash carbon content is higher. the coal inside the furnace stay a short time, Cause a red slag row away.
Excess air coefficient is large, the fuel in the oxygen-rich combustion, fuel can fully burn, mechanical incomplete combustion heat loss is decreased but increases the portion of the exhaust losses.
Excess air coefficient are the important factors to influence the boiler furnace temperature and boiler efficiency, air quantity so big, can make excess air absorb large amounts of heat from the chimney.