Temperature Filed Ansys Simulation in QuenchingProcess of 45 Teel Part

Nonlinear thermophysics parameters are considered in ansys finite element software, so it can be used to compute temperature in the quenching. The temperature field in quenching process of 45 steel part is simulated by ansys finite element software, and the relationship between temperature of part and quenching time is obtained. Simulation result is correspondent with real process, this method has quick computing speed, and it can optimize quenching technology and select quenching bath. The most of all,this method can supply the temperature condition in computation of thermal stress and residual stress of quenching process.     

考虑谷物呼吸的仓储粮堆热湿耦合传递研究

粮食作为生物性多孔介质,具有呼吸特性。一般粮食收获后,大部分时间在密闭不通风状态下存储。以粮堆内局部热湿耦合传递过程作为研究对象,分析了不通风状态下的圆筒形粮仓在自然对流条件下由于温度梯度影响而产生近似冬夏季工况的温度分布和水分转移,借助多物理场数值模拟软件(COMSOL)进行数值模拟,将粮食呼吸作用产热、产湿量以热源、湿源项考虑在数学模型中,通过对温度场、水分场的描述指导工程实践。     

不同通风系统降温效果的数学模拟及试验验证

为了解不同通风系统中粮堆内温度场的变化规律,利用多功能试验仓对稻谷堆进行降温试验,采用数字式温度传感器监测粮堆温度变化,同时通过实仓数据和模拟结果进行验证。利用CFD仿真模拟重现三种通风系统通风过程中的温度变化,且利用MATLAP软件对模拟所得云图进行颜色覆盖面积统计,以此讨论三种通风系统的通风均匀性。结果表明,仓储稻谷堆机械通风过程CFD模型可以准确地反应通风过程中粮堆内部温度的分布情况;横向通风和夹底通风均匀性优于地上笼通风。     

Application of SDL in the Digital System Design

As a standardized formal language, the SDL has widely been used in the software development. In order to extend its application field, it has been explored to use in hardware design.This paper gives a logical gate circuit-and gate as an example to explain the method of applying SDL to describe and simulate/validate the hardware characters by the SDT tool. The various logic circuits or digital circuits may be made to the SDL packages because the SDL supports the object oriented technology. These packages can be directly invoked in the design of the complex digital system, so it is possible to describe and simulate/validate the complex digital system.The experiment has proved that the application of SDL for hardware design is feasible and rather convenient.     

冷藏车内温度场和湿度场的数值模拟研究

应用流体力学（CFD）软件Fluent,采用k-ζ流模型和非稳态求解方法,对加入货物冷藏车的温度场和湿度场进行了三维非稳态数值模拟计算．得到了冷藏车蒸发器区、中心区、货物区以及边壁等处的温湿度分布。冷藏车内流场的数值模拟结果可以为监测与控制冷藏车内的环境提供技术依据。     

农产品空气能热泵烘房温度场的数值模拟与验证

农产品热泵烘房温度场均匀性是影响农产品干燥品质的重要因素。本文选用5HGR-35型农产品热泵烘房,通过交互式CAD/CAM系统(UG)软件建立热泵烘房3D模型,运用理论分析与计算流体动力学(Computational fluid dynamics,CFD)模拟相结合的方法,研究其内部温度场分布情况,对现有结构烘房的温度场建模模拟,分析模拟结果并对现有结构进行优化。通过模拟得出结论:送风速度越大,烘房内热空气更新越快,换热效果越好。综合温度场分布以及农产品烘干要求,烘房内合理的送风速度为11 m/s左右;在11 m/s风速下,烘房空载时在15 min左右达到设定温度(65℃);小推车设计高度加大300~310 mm烘房内部温度场更均匀;烘房顶部均匀加入3块长×宽×高=2900 mm×20 mm×300 mm的挡板,可以使烘房内部温度场更均匀;小推车与烘房之间及相互之间保持30 mm左右间隙摆放更有利于烘房内部温度场的分布;验证试验中,模拟温度与实测温度吻合性良好。上述结论对烘房的进一步优化设计具有一定的指导意义。     

萝卜耐热性鉴定技术体系研究

在田间鉴定指标筛选研究基础上，对萝卜品质和生理生化性状进行分析，筛选出电导百分率及高温致死时间两个指标用于萝卜耐热性鉴定。从萝卜外部形态、产量品质性状、生理生化三个方面入手，采用田间鉴定与生理鉴定相结合的方法，提出了萝卜耐热性鉴定技术体系。该体系包括三种独立的鉴定方法：一是以热害指数为重点，参照苗期单位面积叶鲜重和越夏死株率的田间鉴定。二是以产量和有效根率的产量鉴定。三是利用电导百分率及高温致死时间的生理鉴定。由此形成在萝卜长叶期进行苗期单位面积叶鲜重测定；长根期测定叶片热害指数和越夏死株率，或进行电导百分率和高温致死时间测定；萝卜收获期测定有效根率，最后综合评价萝卜耐热性。三种方法可单独使用，也可合并使用，收到同样效果。     

萝卜耐热性鉴定技术体系研究

在田间鉴定指标筛选研究基础上，对萝卜品质和生理生化性状进行分析，筛选出电导百分率及高温致死时间两个指标用于萝卜耐热性鉴定。从萝卜外部形态、产量品质性状、生理生化三个方面入手，采用田间鉴定与生理鉴定相结合的方法，提出了萝卜耐热性鉴定技术体系。该体系包括三种独立的鉴定方法：一是以热害指数为重点，参照苗期单位面积叶鲜重和越夏死株率的田间鉴定。二是以产量和有效根率的产量鉴定。三是利用电导百分率及高温致死时间的生理鉴定。由此形成在萝卜长叶期进行苗期单位面积叶鲜重测定；长根期测定叶片热害指数和越夏死株率，或进行电导百分率和高温致死时间测定；萝卜收获期测定有效根率，最后综合评价萝卜耐热性。三种方法可单独使用，也可合并使用，收到同样效果。     

The cooling structure of Ni MH batteries in hybrid electric vehicles

Focusing on Ni MH batteries used in hybrid electric vehicles (HEV), a simulation analysis of the flow and temperature fields of the cooling structure in existing batteries is carried out using computational fluid dynamics software. The results show that the temperature uniformity is poor. The uniformity of the flow and the temperature fields is improved by adjusting the baffle and battery positions, changing the tilt angle and the distance between the batteries, inserting wind plates and a coating insulation layer. The coating insulation layer achieves the best effect. Further simulation shows that the coating insulation layer method has the best effects. The results provide the design basis for thermal management program of Ni MH batteries in HEV.     

Computational Simulation on Temperature Field of Slab Continuous Casting Mold

On the core concepts that the distributing of temperature and solidified slab shell in mold are a stable process, a new method to calculate the temperature field in mold has been promoted. Consequently, a coupling model on fluid filed and temperature field in stable state has also been established. The concept of effective heat capacity is introduced to deal with the latent heat source term from phase transformation. During the programming for computation, the dynamic updating method is also applied to simulate the influence of solidification on physical properties. The resolution results of this model are analyzed and compared with the tested thickness of solidified shell from casting broke out slab, which demonstrates the correctness and applicability of this model to the practical continuous casting process. Additionally, the thickness distribution of solidified shell in slab mold are also studied in detail.     

The DSSAT cropping system model

The decision support system for agrotechnology transfer (DSSAT) has been in use for the last 15 years by researchers worldwide. This package incorporates models of 16 different crops with software that facilitates the evaluation and application of the crop models for different purposes. Over the last few years, it has become increasingly difficult to maintain the DSSAT crop models, partly due to fact that there were different sets of computer code for different crops with little attention to software design at the level of crop models themselves. Thus, the DSSAT crop models have been re-designed and programmed to facilitate more efficient incorporation of new scientific advances, applications, documentation and maintenance. The basis for the new DSSAT cropping system model (CSM) design is a modular structure in which components separate along scientific discipline lines and are structured to allow easy replacement or addition of modules. It has one Soil module, a Crop Template module which can simulate different crops by defining species input files, an interface to add individual crop models if they have the same design and interface, a Weather module, and a module for dealing with competition for light and water among the soil, plants, and atmosphere. It is also designed for incorporation into various application packages, ranging from those that help researchers adapt and test the CSM to those that operate the DSSAT–CSM to simulate production over time and space for different purposes. In this paper, we describe this new DSSAT–CSM design as well as approaches used to model the primary scientific components (soil, crop, weather, and management). In addition, the paper describes data requirements and methods used for model evaluation. We provide an overview of the hundreds of published studies in which the DSSAT crop models have been used for various applications. The benefits of the new, re-designed DSSAT–CSM will provide considerable opportunities to its developers and others in the scientific community for greater cooperation in interdisciplinary research and in the application of knowledge to solve problems at field, farm, and higher levels.     

高压正静电场对柠檬表面蜡质亲水性的影响

为探明在静电保鲜过程中不同电场参数对柠檬表皮蜡质亲水分子的影响,以柠檬角质层中成分含量最多的十六烷酸分子为研究对象,用分子模拟与理论分析和试验研究相结合的方法测定高压正静电场对柠檬表皮蜡质亲水性影响。结果表明,利用Materials Studio软件预测出正电场强度为180 kV/m时,十六烷基分子的MSD指数和偶极矩值均达到最小,亲水性最低。进一步用傅立叶红外光谱仪检测到,200 kV/m处理6天对十六烷酸羟基基团的抑制效果最好。最后采用Photoshop软件进行表面润湿性分析,验证在200 kV/m处理6天效果最佳。该试验初步筛选出了适宜柠檬贮藏的高压静电场电磁学的最佳参数,可为今后实际应用过程中选取合适的电场强度提供理论依据。     

Control model for secondary cooling of continuous casting based on compensation temperature of the difference between liquidus and solidus

During continuous casting process, the composition of molten steel often varies with different heats, which leads to the big fluctuation of billet surface temperature when the traditional parameter water control model is applied to control the process. Additionally, it is difficult to keep the temperature at the straightening point of the billet within a reasonable range. Given above consideration, a new control model for secondary cooling of continuous casting based on compensation temperature of the difference between liquidus and solidus has been presented. Meanwhile, the temperature field of the billet is simulated with both the parameter water control model and the new secondary cooling control model, and the results indicate that the new control model for secondary cooling of continuous casting could perform better when it is used to control the surface temperature at straightening points of billet, thereby ensuring the quality of the billet.     

Studies for assessing the influence of hardening on cold tolerance of barley genotypes

Summary Frost tolerance of 30 barley (Hordeum vulgare L.) cultivars have been field evaluated in North Italy during the 1990/1991 winter season that was characterized by exceptionally low temperatures without snow cover. The results showed a significant correlation between cold injury and grain yield loss (r=0.61^**). Five cultivars chosen for their varying degree of frost tolerance were further evaluated using laboratory tests. Measurements of survival rate and membrane damage were used to assess the influence of hardening on frost resistance. The reliability of the tests is shown by the high correlation to the field data. For both the laboratory temperature regimes and field conditions, the tested cultivars showed the same order of classification. The effect of a rise in temperature at the end of the hardening treatment on frost tolerance is also reported. The laboratory tests here proposed can be integrated in a breeding programme for improving frost tolerance in barley.     

Design of Information Terminal in the Water Supply Industry

A information terminal is designed , which is applied to administration and service management in the water supply industry of city. The situation of administration, service management and demand of reform about tradition technology are researched. Combining the advantages of information-processing and movable operation of the pocket PC, a communication model of terminal which can collect data in the field and a processing software are developed . It has the characteristics such as acquisitioning data , service , management, movable operation to traditional water meters, smart card water meters and remote water meters. It has been applied to housing estate and water supply industry at present ,with the widely used ,it improves the situation of management in the water supply .     

基于摩尔库仑准则的膨胀土弹塑性本构模型及其数值实现

膨胀土的应力应变关系与含水量的变化有关，通过室内试验对膨胀土的变形、强度以及膨胀参数与含水量之间的关系进行研究，以湿度应力场理论为基础，提出了一个具有工程实用价值的基于摩尔库仑准则的膨胀土弹塑性本构模型。依据FLAC3D数值模拟软件所提供的二次开发程序，给出了该膨胀土弹塑性本构模型二次开发程序过程的基本原理以及模型的程序框图。结合渗流软件计算的湿度场分布，进行膨胀土基坑边坡实例验算，验证了该本构模型的正确性。     

Discussion on Some Problems of ExpertSystem for Rock Mass Classification

On the basis of discussing present situation for classification of rock masses and necessity of building expert system of rock masses.The intelligent design software for classification of rock masses CRES has been completed. In this paper the CRES is expounded systematically in the following,such as knowledge_base,data_base,reasoning machine,learning machine,and so on.Finally,the CRES is used for verifying 30 engineering examples and is used to classify rock masses of two roadways successfully .The CRES has been connected to SBSDES.     

Heat dissipation optimization of DC-DC and IPU for hybrid electric vehicle

Due to the bad heat dissipation of the existing heat dissipation structure of DC-DC and IPU for hybrid electric vehicle(HEV), the temperature of DC-DC and IPU will rise during the running process, which in turn decreases the stability and reliability of the hybrid electric system. Aiming at this problem, a three-dimensional, transient heat dissipation model is built for DC-DC and IPU heat dissipation structure based on the mass, momentum and energy conservation equations. By using computational fluid dynamics (CFD) software, flow field and temperature field of DC-DC and IPU heat dissipation structure are numerically simulated. Based on the simulation, and combined with heat transfer theory, an improvement scheme of heat dissipation structure is proposed. The simulation results and experiment results of thermal performance and temperature rise show that the improvement scheme can improve the thermal performance, and decrease the temperature rise of DC-DC and IPU effectively, thus satisfy the application requirements in HEV.     

Numerical simulation of the flow and temperature fields in an automotive exhaust muffler

By building a model of a typical exhaust muffler structure, a grid mesh was formed based on the calculation characteristic of the flow field. The software ANSYS CFX then was used to numerically simulate the flow and temperature fields in a muffler. The effects of the gas velocity and temperature variation on sound elimination performance, including the acoustics and aerodynamics performance, were analyzed. The result suggests that high velocity turbulence and high speed flow should be eliminated from muffler structures when designed. At the same time, to provide satisfactory noise elimination, pressure loss should be reduced as far as possible. The pressure loss can be decreased when reducing the perforation structure.     

Study on Software for Hydraulic Model Experiment on Chencun Waterway in Zhujiang Delta

In this paper,the software developed on the basis of Windows platform is introduced, which is used in Chencun Waterway hydraulic model experiment. The efficiency in data analyzing and post processing has been improved. Since the various techniques in Windows platform (such as OLE, DDE) has been adopted, the development works are more efficient and an experimental analytic software with powerful and perfect functions can be developed conveniently.