车用新能源动力电池系统PACK开发设计

动力电池系统是新能源电动汽车动力的来源,作为电动汽车的关键零部件,其设计的合理性和安全性对电动汽车起着至关重要的作用。文章基于某车企需求研发设计一款28 kWh的动力电池系统,主要从电池系统整体结构的排布与设计、电池电气系统的设计、电池热管理系统的设计等三个方面对该动力电池系统进行详细设计和分析。该设计通过结构上尺寸链的分析校核是合理的,以及对其热管理系统进行仿真分析,从而来验证其性能的可行性。此次设计为后续进一步对该电池系统进行优化和试验验证提供了一定的理论基础,也为电池系统开发工作者提供一定的参考价值。

高热耗波导组件的系统级热设计

载荷分系统为航天器实现功能的重要组成部分,随型号设计难度的提高,载荷分系统一般通过提高行波管放大器输出功率来实现性能达标,由此必然导致多工器后级公共端波导热耗过高,对系统级热设计提出更高要求。首先对系统级波导组件热设计方法进行介绍,在此基础上对高热耗波导组件的热分析方法、散热设计及试验验证情况等进行描述。结果表明,在系统热设计无法保证波导使用温度时,需在波导组件上实施散热措施,使用的通用化散热翅片设计简单,安装灵活,利于产品化,经试验验证,最高可将波导温度降低25℃左右。

基于建筑信息模型的建筑热工系统与暖通空调系统设计应用分析

以建筑信息模型(building information model,BIM)为出发点,结合某高校综合实验室工程建设项目,研究了BIM技术在建筑设计中的应用。分析了基于BIM技术与权衡负荷判断法的建筑热工系统优化设计方法的可行性;讨论了基于BIM技术的建筑能耗模拟存在的问题及BIM技术在建筑热工系统与暖通空调系统设计中的应用;分析了现阶段我国BIM技术应用的发展趋势。

热采井口装置伴热系统的设计与应用

九6区位于八道湾组油藏,这里的油井普遍油稠(20℃时最高粘度达到650595.12mPa·s,特别是在冬季更为严重,油井停井伴热次数频繁,采油时率低,严重影响了作业区原油产量的完成。通过对井口装置伴热系统的重新设计,实现了伴热时蒸汽可以通过套管进入井底的不间断生产伴热,延长了油井的采油周期,提高了油井的采收率。

近零能耗居住建筑新风热回收系统设计的优化

文章阐述了国内新风热回收系统应用存在的主要问题,说明了国内新风热回收系统应用问题的解决措施,分析了新风热回收系统设计的优化要点,探究了新风热回收系统的智能化运行。

热泵系统设计分析

分析了热泵系统与常规空调系统不同之处,指出造成热泵系统故障的主要原因.针对这些原因给出了空气-空气热泵系统设计中应采取的一些措施,包括压缩机选择、制冷剂控制、气液分离器采用、高压控制、压缩机不间断运行和曲轴箱加热器等,为热泵系统可靠、安全、高效地运行奠定基础.

核电常规岛热控电源系统设计探讨及在秦山核电二期常规岛上的实现

本文借鉴大型火电厂热控电源设计经验，以秦山核电站二期工程常规岛热控电源设计为例，对核电站常规岛热控电源设计进行分析和研究。

火电厂热工自动化系统设计中节能减排技术的应用

在火电厂热工自动化设计中,节能减排技术的应用,可以将火电厂企业的能源消耗降低,并且使得火电厂运行成本减少,因此,在热工自动化设计当中,就需要加强对节能减排技术应用的重视,除了能够对于火电厂热工自动化设计需求可以满足,也可以对于设计成本实现合理控制,对于火电厂自身经济效益的提升有着很重要的作用。基于此,本文就对火电厂热工自动化系统设计中节能减排技术的应用进行探讨和分析。

重庆地区地表水水源热泵系统经济性评价方法

建立了重庆地区地表水水源热泵系统经济性评价模型,确定了重庆地区地表水水源热泵系统能耗设计指标限值E2限值,并给出热泵系统能耗设计指标的简化计算方法,若热泵系统能耗设计指标E2≤E2限值,则认为该水源热泵系统是经济的。

热管散热在大功率电源系统中的运用

大功率军用电源系统的散热设计,对整个系统能否稳定可靠运行,起着极其重要的作用。本文以一个设计案例为基础,通过对系统整体散热方式的选择,到具体从模块散热形式的确定,概括的作了介绍。

空气源热泵制备热水的三种系统分析比较

本文介绍了空气源热泵系统在广西某党校中的应用。空气源热泵系统是热泵热水系统的关键，空气源系统的管路系统又是系统的核心。管路系统的设计是否合理，直接影响了整个系统的运行。本文重点介绍了空气源热泵的不同系统的选取、系统控制的差异、不同系统的优缺点等问题。

Thermal performance analysis of borehole size effect on geothermal heat exchanger

Thermal performance was the most important factor in the development of borehole heat exchanger utilizing geothermal energy. The thermal performance was affected by many different design parameters, such as configuration type and borehole size of geothermal heat exchanger. These eventually determined the operation and cost efficiency of the geothermal heat exchanger system. The main purpose of this work was to assess the thermal performance of geother^nal heat exchanger with variation of borehole sizes and numbers of U-tubes inside a borehole. For this, a thermal response test rig was established with line-source theory. The thermal response test was performed with in-line variable input heat source. Effective thermal conductivity and thermal resistance were obtained from the measured data. From the measurement, the effective thermal conductivity is found to have similar values for two- pair type （4 U-tubes） and three-pair type （6 U-tubes） borehole heat exchanger systems indicating similar heat transfer ability. Meanwhile, the thermal resistance shows lower value for the three-pair type compared to the two-pair type. Measured data based resistance have lower value compared to computed result from design programs. Overall comparison finds better thermal performance for the three-pair type, however, fluctuating temperature variation indicates complex flow behavior inside the borehole and requires further study on flow characteristics.

Heat absorption control equation and its application of cool-wall cooling system in mines

In order to solve the heat damages in deep mines, a cool-wall cooling technology and its working model are proposed based on the principles of heat absorption and insulation in this paper. During this process, the differential equation of thermal equilibrium for roadway control unit is built, and the heat adsorption control equation of cool-wall cooling system is derived by an integral method, so as to obtain the quantitative relationship among the heat absorption capacity of cooling system, the heat dissipating capacity of surrounding rock and air temperature change. Then, the heat absorption capacity required by air temperature less than the standard value for safety is figured out by section iterative method with the simultaneous solution of heat absorption control equation and the heat dissipation density equation of surrounding rock. Finally, the results show that as the air temperature at the inlet of roadway is 25 ℃, the roadway wall is covered by heat-absorbing plate up to 39% of the area, as well as the cold water is injected into the heat-absorbing plate with a temperature of 20 ℃ and a mass flow of 113.6 kg/s, the air flow temperature rise per kilometer in the roadway can be less than 3 ℃.

A numerical study on heat transfer enhancement and design of a heat exchanger with porous media in continuous hydrothermal flow synthesis system

The aim of this study is to use a new configuration of porous media in a heat exchanger in continuous hydrothermal flow synthesis(CHFS)system to enhance the heat transfer and minimize the required length of the heat exchanger.For this purpose,numerous numerical simulations are performed to investigate performance of the system with porous media.First,the numerical simulation for the heat exchanger in CHFS system is validated by experimental data.Then,porous media is added to the system and six different thicknesses for the porous media are examined to obtain the optimum thickness,based on the minimum required length of the heat exchanger.Finally,by changing the flow rate and inlet temperature of the product as well as the cooling water flow rate,the minimum required length of the heat exchanger with porous media for various inlet conditions is assessed.The investigations indicate that using porous media with the proper thickness in the heat exchanger increases the cooling rate of the product by almost 40% and reduces the required length of the heat exchanger by approximately 35%.The results also illustrate that the most proper thickness of the porous media is approximately equal to 90% of the product tube's thickness.Results of this study lead to design a porous heat exchanger in CHFS system for various inlet conditions.

Thermodynamic design of a cascade refrigeration system of liquefied natural gas by applying mixed integer non-linear programming

Liquefied natural gas(LNG) is the most economical way of transporting natural gas(NG) over long distances. Liquefaction of NG using vapor compression refrigeration system requires high operating and capital cost. Due to lack of systematic design methods for multistage refrigeration cycles, conventional approaches to determine optimal cycle are largely trial-and-error. In this paper a novel mixed integer non-linear programming(MINLP)model is introduced to select optimal synthesis of refrigeration systems to reduce both operating and capital costs of an LNG plant. Better conceptual understanding of design improvement is illustrated on composite curve(CC) and exergetic grand composite curve(EGCC) of pinch analysis diagrams. In this method a superstructure representation of complex refrigeration system is developed to select and optimize key decision variables in refrigeration cycles(i.e. partition temperature, compression configuration, refrigeration features, refrigerant flow rate and economic trade-off). Based on this method a program(LNG-Pro) is developed which integrates VBA,Refprop and Excel MINLP Solver to automate the methodology. Design procedure is applied on a sample LNG plant to illustrate advantages of using this method which shows a 3.3% reduction in total shaft work consumption.

Study and practice of the controlling technique on heat-harm during the tunneling in Zhaolou mine

This paper proposes the cooling system type and cooling equipment type which are deep mine with high temperature during the construction,and presents auxiliary cooling measures making up duct temperature rise since compression and heat transfer temperature rise. The cooling system designed against Zhaolou mine's ground temperature and weather conditions,with its sprinkler room handling an average temperature difference up to 19.5～23.8 ℃,and the average enthalpy difference could reach 48.4～60.7 kJ/kg. At the same time,it gets a series of basic data used for mine construction during the cooling system design and equipment selection according to the measured results; using the analysis software Matlab,it obtains the change relations between the temperature of sprinkler room and fan export supply air temperature,wind casing temperature rise and fan export supply air temperature,working face temperature and supply air temperature,used for the mine cooling which has the similar conditions.

Exergy Analysis of Single and Multi-Step Thermal Processes

The present paper introduces the concepts of exergy and treats it applications to analysis of the gain in exergy efficiency between one-step and multi-step thermal processes. The analysis, which is carried out with the Excel-based SEPE program, is exemplified with the comparison between single-step and two-steps heat pump setup for providing heat to a floor heating system and for domestic hot water. The paper discusses the use of the concept of exergy efficiency as a measure of success for design of a heat pump application and how the use of information on exergy destruction and temperature levels in different parts of the system add a new perspective to the analysis and the evaluation of the system performance. The paper shows how this information can be used to improve the system configuration and also the operation of the system for given boundary conditions. This is especially useful when the energy from the low temperature sources can be utilized at different temperature or quality levels such as for space heating and domestic hot water.

新型带热回收装置的热泵空调系统的应用研究

传统的风冷式热回收热泵系统只有在制取生活热水这段时间内是高效运行的,而传统的水冷式热泵系统难以实现冬季的热泵循环,设计一种新型的风水冷热水空调系统,在热回收器上连接冷却塔,在夏季制冷运行中,将不需要热回收的那部分热量完全通过冷却水带走,保证系统都能在较高性能系数的状态下运行。经过实际工程运行验证,系统的最高制冷性能系数可以达到3.5,最高综合性能系数可以达到6.5,达到了节能的目的。

Design and Validation of Strategy to Increasing the Rate Calving in Traditional Production System Livestock of Michoac^n M^xico Tropical Dry

Michoacan brings 2.1% of national GDP, which is 12.5% to agriculture, Livestock is the fourth activity in economic importance in the State and develops in 43% of the territory （58,643 km：） using 27% of the population economically active. Michoacfin ranks third in national cattle inventory （1,608,523 heads） with fifth place in meat production （145,221 ton/year）. The production model is extended cow-breed, subject to season and availability of food （few rains shortage of forage during drought）, with 0.60 production of breed/cow/year, and a marked traditionalism in the form of production; also a high dependency to food based on the grazing. The inadequate national public policy expressed in the paternalism has limited the adoption of strategies to contribute to the solution of this problem. Therefore this study objective was to design and validate a strategy to increase the number of cow breeding/cow/year to season reproduction program, based on the use of synthetic progesterone ＂melengestrol acetate＂ （MGA） as a technology available, secure, easy to use, low cost and likely to be adoptable to the traditional model of production. Work was done in the dry tropics in the municipalities of Churumuco and Tzitzio, Michoacfin State, Mdxico. Used 133 bovine females with crossbreeding Bos indicus, diagnosed as not pregnant, 6.7 and 6.38 years old respectively for each municipality. Oral doses of 0.05 rag/day/cow of MGA during nine days then exposed to the presence of male. Data were analyzed using analysis of variance of a single way. The results indicate that the delivery rate was 58.33% in Churumuco and 61.86% in Tzitzio. This delivery rate represents an increase of 14%-16% of born per year considering that treated females become pregnant with traditional production system management. We concluded that the MGA is an appropriate strategy to the traditional production of tropical dry in MichoacO, n system that increases the rate of births and is likely to be accepted despite the paternalistic public policy prevailing in the country.

Computer Controlled High Precise, High Voltage Pules Generator

High precise, high voltage pulse generator made up of high-power IGBT and pulse transformers controlled by a computer are described. A simple main circuit topology employed in this pulse generator can reduce the cost meanwhile it still meets special requirements for pulsed electric fields (PEFs) in food process. The pulse generator utilizes a complex programmable logic device (CPLD) to generate trigger signals. Pulse-frequency, pulse-width and pulse-number are controlled via RS232 bus by a computer. The high voltage pulse generator well suits to the application for fluid food non-thermal effect in pulsed electric fields, for it can increase and decrease by the step length 1.