The application of rough sets-neural network theory to mine ventilation system evaluation

To solve the instability problem of established sample in the neural network evaluation method for mine ventilation system, a comprehensive evaluation of the ventilation system is carried out based on rough sets and BP neural networks. Taking the ventilation system of a mine as an example, the classification quality of raw data samples are tested by using rough set data analysis system. Then, based on artificial neural network theory, a rough sets-neural network evaluation model of a mine ventilation system is established and a new rough sets-neural network evaluation method of mine ventilation system is formed. The results show that, after the model validation of data and application, its theoretical evaluation results are in line with the actual situation, and the network total error is less than 0.004. It shows that the comprehensive evaluation method based on rough sets-neural networks has a good effect in evaluating mine ventilation system in practical application.     

Analysis on cooling load on hot mine

Air stream of hot mines is taken as research object, and energy balance equation is established. Cooling load expressions under five different conditions are derived through strict theoretical derivation, i.e. unsteady multi-stream, steady flow, steady flow ignoring kinetic energy change, steady flow ignoring potential energy change and steady flow ignoring fan power change. Then the enthalpy variable expression of the subsurface moist air and heat calculating process of surrounding rock are deduced. Finally, Yong Chuan coal mine illustrates and summarizes the process of calculation cooling load quantitatively. It is conducive to scientificly manage hot mine and design mine ventilation.     

Traditional mineral resource visualized dynamic estimation and its application in 3D geological space

A new method for traditional mineral resource visualized dynamic estimation in 3D geological space is proposed, which is adaptive to the characteristics of resource exploitation and reserve classification in China. The method follows the daily workflow of mine exploitation, improves the traditional method for resource estimation by 3D visualization technologies, and replaces abstract regular geometries with real 3D geological models. Thus, the traditional method for resource estimation realizes visualization in the whole workflow of mine exploitation. The application results to some real mines show the estimation results are mainly affected by the spatial location, shape and thickness of mineral blocks and goaf. If the resource dynamic estimation is carried out by constructing 3D mineral models in consistent with real exploitation project, the accuracy of the traditional method can be effectively improved.     

The Experiment of Prevention Accumulated Methane by Means of Abnormal Y Pattern Ventilation Method

In this paper, according to the experiment of abnormal Y pattern ventilation method in Coal Face 22160, Mine 10, Pingdingshan Coal Group Ltd. Co. , it is discussed that the effect of ventilation method on fugitive air and gas emission. It is discovered that Y pattern ventilation method can not only decrease air break in mine goaf by means of declining intake air in drawing road, and alleviate gas emission in gob area, but also wash the accumulated methane in upper corner by means of fresh air in middle road, and reduce the gradient of gas concentration greatly in direction of dip in upper half part of mining face and the gas concentration in upper corner. That can effectively prevent gas accumulation in mechanized high gas faces and provide reliable guarantee for high production and high effectiveness in mechanized high gas faces.     

Analysis of Fire Smoke Movement with Different Air Velocity at the Stair head to the Hall of a Metro Station

When a fire happens at the subway platform, the downward ventilation at the staircase which connects the hall and platform can prevent smoke spreading into the hall and provides guiding air for evacuation people. To investigate the influence of the ventilation rate on the smoke movement, the air velocity at the staircase was measured under three ventilation modes. Numerical model was established to simulate the real fire scenario. It is shown that the downward air velocity under fire is greater than that without fire, and the traditional design procedure without considering complex factors interaction in real fire scenario should be improved; when fire is near the staircase, smoke easily spills from the smoke screen to the concourse. And smoke concentration of concourse is even higher than that of platform because the hall is under air supply mode; when the fire locates at the public area of the platform, turning on the tunnel fans can increase the downside flow at the staircase. However exceeding high flow can produce disturbance and destroy the smoke stratification, so more area will be filled with smoke. Therefore, reasonable smoke management scheme is as important as smoke exhausting system capability.     

The application of deep hole pre-split blasting to gas improved extraction in high hydrogen sulphide mine

As the present result of gas extraction by conventional methods in soft low permeability of high-gas mine is not satisfying, deep hole presplitting controlling blasting technology is adopted in Changwu Tingnan coal mine, Shaanxi province. The amount of a single drilling gas extraction increases by 1.36 times, face gas extraction rate edges up to 50% and seam permeability coefficient increases by 9 times. By taking some comprehensive measures, such as enhancing ventilation, drainage, extraction of hydrogen sulfide and lime slurry injection in the blast holes, the hydrogen sulphide is controlled in advanced and the concentration is controlled blow 2×10 -6~4×10 -6, thus the working environment is effectively improved and the safety in production is ensured.     

Application of Indoor Natural Ventilation Simulation in Residential Space Layout

Tatural ventilation of indoor air flow and thermal comfort space plays an important role, especial y in the interior design of passive cooling factors, indoor space layout, and the location of doors, windows and other factors on the indoor natural ventilation effect has great influence. Using the method of fluid mechanics, and Airpak3.0 software, indoor natural ventilation for residential buildings was simulated, and the thermal comfort of indoor natural ventilation in a residential building in Xuzhou City was analyzed to explore the effect of indoor spatial layout, location of doors, window opening types on indoor natural ventilation. The results showed that indoor spatial layout played an essential role in indoor natural ventilation, application of numerical simulation for the simulation of the indoor natural ventilation and assessment of indoor natural ventilation effect was a scientific instruction for the indoor spatial design.     

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。     

机械通风降温中的节能与节支

储粮机械通风降温技术为最佳储藏技术之一．通风时段,通风次数、通风形式以及终极粮温的选择直接关系到储粮效果和节能、节支．     

高大平房仓立体机械通风技术研究

为解决高大平房仓机械通风不均匀等问题，在原有平面通风道的基础上，于粮堆中增设相应数量的直竖式通气竹笼，使之形成粮堆立体通风网络。试验表明：可提高通风效果和均匀度，消除死角，加快降温速度，缩短通风时间，节约费用，为立体通风提供一条新途径。     

平房仓横向通风技术在玉米储藏上的应用研究

为了研究平房仓横向通风技术在玉米储藏上的应用效果,明确玉米储藏过程横向通风工艺及其参数,利用高大平房仓中设计安装的横向通风设施,以及在储藏玉米粮堆中预埋的插入式毕托管,对高大平房仓横向通风系统进行实仓测试。全面开展了玉米储藏过程中横向通风工艺应用研究,测试了在横向通风系统通风时,风速、风量、系统各部分阻力和粮堆压力分布。研究发现,在储藏玉米的高大平房仓中应用横向通风系统时,粮堆单位粮层阻力较小,在实用单位通风量时,横向通风系统总阻力不大于1200Pa;同时横向通风还具有风量分配均匀、粮堆通风均匀性良好的特点。该研究为玉米在配备横向通风系统的高大平房仓储藏提供了技术支持。     

储粮机械通风系统设计中不容忽视的两个问题

探讨了储粮机械通风系统的优化设计,即风机的合理选择和均匀送风管道的设计,可节约能耗,促进机械通风储粮技术的规范化。     

基于数值模拟技术的三种通风量下储粮机械通风效果的比较研究

基于多孔介质的传热传质理论,建立了储粮通风过程中粮堆内部热质耦合传递的控制模型,并借助数值模拟的方法,模拟分析了三种通风量下粮仓垂直通风时,粮仓内各粮层的温度、水分变化规律,以及各种通风量下的通风效果,研究结果可以为储粮通风操作提供参考。     

通风方式对有机肥发酵过程中理化性质的影响

为寻找有机肥发酵的最佳通风方式,采取对比试验方法研究了不通通风方式对堆肥发酵过程中理化性质的影响.结果表明：不同通风方式堆肥发酵过程温度伴随氧气浓度的降低而升高,温度高于50℃或55℃天数以翻堆3次处理最多,氧气浓度以翻堆3次与间歇式通风相结合处理表现明显.不同通风方式发酵过程中总N含量呈上升趋势,总C、C/N比、有机质含量呈下降趋势,3个处理总养分含量、pH值差异较小,以翻堆3次与间歇式通风相结合处理成品率最高.总体上,以翻堆3次与间歇式通风相结合最有利于有机肥发酵.     

Analysis and Calculation of Ventilation System of Xuefengshan Highway Tunnel

Some problems about ventilation in extra long highway tunnels have been discussed in this paper. The ventilation modes and geometry parameters of longitudinal blow-suction ventilation of Xuefengshan Tunnel in Hunan Province (7 000 m) have been studied and calculated. Based on this, the general design, principle design, technical design and relative structural design of ventilation for the tunnel have been successfully done.     

大型房式仓储粮通风系统的设计

详细介绍了与新建国家粮食储备库仓型相近的大型房式仓的储粮通风系统设计及地槽防水防潮措施。储粮通风试验表明，该系统通风效果良好，在江苏洪泽湖水网地区也可起到良好的防潮作用。     

浅圆仓散储玉米局部发热的处理

对线圆仓散储玉米局部发热进行全面通风和局部通风的对比试验，结果表明：采用全面大风量通风，降温、降水缓慢，通风不彻底，发热容易复发；采用局部小风量通风，针对性强，降温、降水速度快，能有效防止粮堆再次发热。     

智能通风技术在保水降温通风中的实践应用

智能通风系统自动采集大气温湿度和监控粮情变化,按构建模型进行智能分析,自动捕捉通风时机进行通风;通风过程中,根据流出气体温湿度等反馈的即时粮情、大气温湿度等数据,判断是否继续通风,从而避免了低效通风、无效通风和有害通风,取得了在降温通风中减少水分损耗、节能降耗的良好效果。     

Simulation of Auxiliary Ventilation Performance of Synthetic Solar House

The passive solar house is one of the effective techniques to decrease the energy consumption of buildings. In this paper, the ventilation performance of synthetic solar house with sunshine room has been analyzed, while it is used as auxiliary ventilation in summer. The mean temperature of air in this room is calculated through the model of heat transfer of solar room, and then the auxiliary ventilation quantity is calculated. It is concluded that the capacity of auxiliary ventilation of synthetic solar house can meet the fresh air demand of common residential construction, but if there are more ventilation quantity needed the capacity of auxiliary ventilation of synthetic solar house is insufficient. The simulation calculation provides the necessary theoretical basis for the further theoretical and experimental research on synthetic solar house.     

简易温控装置在轴流风机保水降温通风中的运用

轴流风机常用于保水降温通风,通风时间相对延长,把握最有利低温时机较难,保管员工作量相对增大,将简易温控装置应用于轴流风机保水通风过程中,既能解决把握低温通风时段难和保管员工作量相对增大的问题,又能达到降温、保水和降低通风单位能耗的目的。