散热器与低温地板辐射联网供暖系统设计

针对单热源且同时存在散热器供暖与低温地板辐射供暖联网的供暖系统,分析了混水泵并联管网和带旁通的串联管网两种不同形式的供暖系统各自的结构特点、参数选择和优缺点,并给出了两种系统的适用情况。     

两级涡轮增压对轻型柴油机性能影响的试验研究

在某轻型柴油机上设计了两级涡轮增压系统,进行了匹配两级涡轮增压的试验研究。研究结果表明,在较低转速高负荷工况,废气全部流经高压级增压器可以改善经济性,在较低转速低负荷工况,将进气旁通阀和废气旁通阀全开能够减小排气背压和进气节流损失,降低比油耗;在较高转速,进气旁通阀和废气旁通阀全开的经济性更好。经济性优化情况下,两级增压相对原机单级增压可以明显降低低速段和高速段的比油耗,外特性低速段的比油耗最大降幅达到21 g/（kW.h）,标定转速也降低了10.5g/（kW.h）,发动机的万有特性经济运行区明显变宽。     

燃气-蒸汽联合循环无旁通烟囱余热锅炉煮炉方案的选择

论述了无旁通烟囱余热锅炉的启动特点；介绍了过热器应力腐蚀现象，指出对无旁通烟囱余热锅炉不可采用常规的方式煮炉，给出了两种切实可行的煮炉方案。     

小型航空活塞发动机二级增压方案的仿真分析

根据某小型航空活塞发动机功率恢复的需要,提出了两种不同的二级增压系统方案,即可调二级增压系统和带旁通阀的可调二级增压系统。研究结果表明,两种二级增压系统方案均能较大幅度提升发动机的运行高度;相比较,带旁通阀的可调二级增压系统在提升发动机性能方面具有更大的优越性。     

燃气—蒸汽联合循环无旁通烟囱余热锅炉煮炉方案的选择

论述了无旁通烟囱余热锅炉的起动特点，介绍了过热器应力腐蚀现象，指出了对于无旁通烟囱余热锅炉不可采用常规的方式煮炉，给出了两种切实可行的煮炉方案。     

1000 MW等级超超临界凝结水泵配置优化分析

凝结水泵的配置方式对火电机组运行经济性影响较大.在调研国内外1000MW等级机组凝结水泵的配置现状的基础上,分析凝结水泵两种典型配置方式的技术可行性、运行可靠性和经济性,计算对应的初始投资和年运行费用.得出凝结水泵的最佳配置方式为采用2×100％容量凝结水泵、两台水泵共用一套1×100％电机变频装置,该配置方式技术成熟...     

可调二级增压柴油机旁通阀特性和调节规律的试验

对柴油机应用可调二级增压系统进行了全工况的试验研究.结果表明,涡轮旁通阀可以对增压压力进行调节进而影响柴油机的性能.可调二级增压系统可以增大柴油机中低转速的增压压力,改善碳烟排放;当循环供油量增加后还可以提高中低速时的外特性转矩.中低转速中高负荷时,两级增压会提高进气量改善燃烧,明显地提高了燃油经济性.中高速时,进气量的提高没有明显地改善燃烧的效果,反而造成泵气损失增大,基于经济性考虑应开启涡轮旁通阀,与此同时为避免节流效应压气机旁通阀也应开启将高压级增压器完全旁通,旁通后由于复杂的进排气管增加了流动损失使得油耗略有升高.     

热水采暖系统两种补水方式的耗能分析

<正> 利用水射器代替热水采暖系统补给水泵完成系统补水任务的补水方式,是近年来热水采暖领域出现的一项新技术。该方式的特点是省去了系统的两台补给水泵,可减少系统初投资,且因水射器无可动部件还可减少日常维修工作量。但是由于水射器是一种效率较低的扬水工具(最高效率仅为30%),而一般离心式水泵效     

带不同类型调节阀的二级增压系统结构与性能对比

对带外置式蝶阀的二级增压系统和带内置式旁通阀的二级增压系统进行了结构和性能比较.从结构上看,带内置式旁通阀的二级增压系统结构更为紧凑,但2个涡轮箱都需要重新设计.由试验结果可知,带外置式蝶阀的二级增压系统具备更大的流量调节能力,可实现高压级增压器的短路,带内置式旁通阀的二级增压系统旁通废气量可达总流量的30%以上.     

两机三泵技术在湿冷火电机组节能工作中的应用

介绍了湿冷火电机组循环水泵两机三泵运行方式优化技术在实际运行中的成功应用经验,通过理论分析和实际试验,不断改进实际设备系统,最终解决了两塔水位不平衡等技术难题,成功实现了两机三泵运行优化。该技术的应用使循环水泵电耗在降低0.03%的同时,机组真空提高了0.54 kPa,节能效果十分显著,具有推广应用价值。     

含变频泵泵站动态规划优化模型的敏感性分析

泵站实际运行时的运行参数不一定能符合泵站最优数值,为研究模型实际运行的特征及相关参数的敏感性,基于已建立的含变频泵的泵站优化调度的能耗模型和日运行电费优化模型,采用全局敏感性分析Morris法,以瞬时流量、瞬时扬程及日调水量、日均扬程和峰谷最大最小流量为变量参数,改变其取值范围得到含变频泵的单级泵站对应敏感性参数下模型输出结果,并进行敏感性分析得到实际运行的特征。结果表明,能耗、电费、单位流量能耗和单位水量电费随瞬时流量、日调水量的增加而增加;能耗、电费随扬程的增加而增加,单位扬程能耗、单位扬程电费在设计扬程32.15m处最少,最节能,性价比最高;在不超过机组承受能力和满足各种运行条件的情况下,高峰时段能运行的最小流量越小,整个泵站日运行电费越低;低谷时段可运行的最大流量越大,整个泵站日运行电费越大。研究结果为全面了解泵站的实际运行特征及指导实际运行提供借鉴。     

Evaluation and optimization of water source heat pump for district heating: A case study in steel plant

Using high-temperature heat pump technology to recover waste heat of circulating cooling water in a steel plant for central heating system not can only reduce the temperature of circulating cooling water to meet the needs of smelting process but also can save energy and protect environment as well as bring great economic benefits to steel plant that can sell heat to the heat users. The energy consumption equation of heat pump central heating system was established based on the energy consumption of heat pump, energy consumption of water pump, and heat loss. The optimal inlet water temperature, inlet flow rate, and the number of operating heat pump modules at different outdoor temperatures were calculated by genetic algorithm. The superiority and operating control strategy of heat pump central heating system were discussed. The results show that with the increase of outdoor temperature, the optimal inlet flow rate and the number of operating heat pump module decrease. However, the inlet water temperature almost does not change. It is more suitable for the heat pump central heating system to change the inlet flow and the number of operating heat pump modules. The operating control strategy equation was established by linear fitting, which provides guidance for the engineering application of heat pump central heating system.     

LiBr-H_2O太阳能吸收式热泵海参干燥系统应用分析

提出以LiBr-H2O为工质对的太阳能吸收式热泵海参干燥系统,介绍此系统的组成及工作流程。LiBr-H2O太阳能吸收式热泵应用于干燥过程可以降低能耗,绿色环保。对其应用前景进行分析,同时提出该系统在推广应用方面的限制因素,对太阳能吸收式热泵海参干燥装置设计及推广具有参考价值。     

Modelling and validation of a gas engine heat pump working with R410A for cooling applications

Gas engine heat pumps play an important role in energy saving and environment protection in both cooling and heating applications. In the present work, a thermal modelling of the gas engine driven heat pump in cooling mode is performed and system main parameters such as cooling capacity, gas engine energy consumption and primary energy ratio (PER) are computed. The modelling of the gas engine heat pump includes modelling of the scroll compressor, the plate evaporator and the gas engine. Discharged refrigerant mass flow rate and compressor power represent the main output parameters of the compressor semi-empirical model. Using the discharged refrigerant mass flow rates along with the available evaporation heat transfer correlations, the system cooling capacity is deduced. Based on the present experimental data, a correlation of gas engine energy consumption as function of compressor power, engine speed and ambient air temperature is obtained. Furthermore, the gas engine heat pump model is validated by comparing experimental and simulation data. The model error percentages to predict the cooling capacity, the gas engine energy consumption and the PER are 7%, 5%, 6% respectively.     

空调冷冻水变主流系统运行能耗分析

比较了单级泵、双级泵、变主流系统等三种冷冻水系统的特点 ,对其能耗进行了对比分析 ,认为变主流系统能耗低、系统简单 ,有广泛的应用前景     

Energy consumption modeling of air source electric heat pump water heaters

Electric heat pump air source water heaters may provide an opportunity for significant improvements in residential water heater energy efficiency in countries with temperate climates. As the performance of these appliances can vary widely, it is important for consumers to be able to accurately assess product performance in their application to maximise energy savings and ensure uptake of this technology. For a given ambient temperature and humidity, the performance of an air source heat pump water heater is strongly correlated to the water temperature in or surrounding the condenser. It is therefore important that energy consumption models for these products duplicate the real-world water temperatures applied to the heat pump condenser.This paper examines a recently published joint Australian and New Zealand Standard, AS/NZS 4234: 2008; Heated water systems – Calculation of energy consumption. Using this standard a series TRNSYS models were run for several split type air source electric heat pump water heaters. An equivalent set of models was then run utilizing an alternative water use pattern. Unfavorable errors of up to 12% were shown to occur in modeling of heat pump water heater performance using the current standard compared to the alternative regime. The difference in performance of a model using varying water use regimes can be greater than the performance difference between models of product.     

变频技术在高压注水泵上的应用

通过对孤三注水站进行系统效率能耗分析,结合孤三注水泵实际运行排量波动较大．注水泵偏离高效区运行这一现状,采用高压变频技术对孤三注水站进行改造,实现注水泵的转速随工况任意调节,泵压与干压基本趋于一致,减少节流损失,降低注水单耗。     

孤东二号联三环节能流分析

为了提高孤东二号联用能效率,需要分析该站用能的薄弱环节,采用三环节方法对该站的能流分布进行了深入分析。首先建立了联合站的能流图,然后在加热炉等主要能耗设备用能分析的基础上找出能量转化与传输环节、能量利用环节和能量回收环节的主要问题。分析结果显示,加热炉效率低、设备散热损失大、泵机组效率低、高含水加热等是孤东二号联主要的用能薄弱环节,为进行节能优化提出了工作方向。     

南方城区某优质水厂供水量与耗电量关系预测模型

目前,关于水厂供水量与耗电量关系的定量研究较少。对此,以南方某优质水厂2012~2014年供水量和耗电量生产数据为基础,引入季节指数平滑法改进传统灰色模型,预测具有季节性周期变化的月生产数据,分别建立了出水泵耗电量、净水工艺耗电量、综合楼耗电量以及优质水厂出水泵供水量的季节-灰色预测模型。预测结果表明,四个模型精度较高且稳定性较好,对应的平均绝对误差分别为6.18%、4.82%、4.46%、6.12%,相对误差的方差分别为0.05、0.04、0.03、0.03。引入表示供水量与耗电量之间关系的特征参数即能量强度,结合各模型的计算结果预测优质水厂能量强度,建立了能量强度预测模型。结果表明,模型预测值与真实数据吻合良好,平均绝对误差为4.49%,相对误差的方差为0.03。结研究果可为优质水厂日后设备维护、更新及未来水厂二期建设提供依据。     

黄登水电站水轮机转轮上冠泵板对顶盖取水的影响

针对不同上冠斜置泵板结构方案影响黄登水电站机组顶盖取水的问题,基于计算流体动力学(CFD)和工程流体力学的基本理论,以商用CFD分析软件为平台,从顶盖取水口压力、上冠轴向水推力和泵板能耗的角度,分析了辐射径向布置泵板及泵板逆转轮旋转方向斜置30°、45°三种方案7种工况下的上冠流道内部流动特性。结果表明,斜置45°的泵板结构能获得最大的取水压力且产生的上冠轴向水推力最小,斜置30°的泵板结构能耗最低,在顶盖取水系统设计中应根据水轮机运行工况范围特点选择不同的泵板结构。