电子厂净化空调设计实例

介绍了某电子厂洁净车间的空调系统设计要求和设计方案，实施效果，给出了系统划分，风量计算和气流组织的方法，并指出：计算倍频中心噪声量，针对超标频率采用廉价不锈钢网，无纺布等做成消音器，可经济有效地控制空调噪声。     

太阳能发电系统的最佳化设计

独立光伏发电系统需要进行最佳化设计。介绍了一种简明合理而又实用的最佳化设计方法。应用目前国外常用的倾斜面上太阳辐照量的计算公式，根据不同的蓄电池维持天数，应用能量平衡原理，得到相应的太阳电池方阵最佳倾角，然后通过循环计算，得出一系列太阳电池方阵和蓄电池容量的组合，再通过经济核算等，最后确定光伏系统的规模，编制了相应的计算机程序，并进行了实例计算。     

汽轮机滑动轴承设计专家系统的开发

采用面向对象的设计方法和专家系统理论，以《汽轮机径向滑动轴承性能计算》（ＪＢ／２２０９－８４）为知识集，用Ｃ＋＋语言开发了一个基于Ｗｉｎｄｏｗｓ的面向对象的滑动轴承设计专家系统ＪＢＥＳＦＷＩＤ。该系统完成了从轴承结构型式选取、经验参数选择、性能计算、结果分析评价和输出的全过程。面向对象的方法和Ｗｉｎｄｏｗｓ的应用，使该系统具有良好的基于图形的人机界面，操作简单，便于维护和使用。     

活塞环螺施撑簧设计计算法

本文较系统的介绍了螺旋撑簧的计算方法。通过提出的设计原则、计算步骤和计算表可以很文方便的研究撑簧材料和结构尺寸；通过分析主要尺寸及其对弹力的影响，提出调整弹力的方法。具有一定的实用性。     

太阳电池供电系统设计简化计算方法

该文针对太阳电池供电系统设计计算时公式繁多、数据分散的问题，提出一种简单、实用的计算方法。经系统运行验证，这种简化计算方法实用可行。对于太阳电池的推广、普及，该方法具有技术指导作用。     

加热炉速冷系统的设计

通过阐述风机的选型计算,系统流动损失计算和换热器的设计计算,详细地介绍了炉膛充氩加热炉速冷系统的设计方法。工件温度随时间变化的计算结果与实际测量值基本吻合。流动损失和风机的选型计算目的在于使所选风机在高效区内工作,换热器的计算旨在设计换热器列管的直径、根数和长度。     

低温地热供热系统的设计与质调节问题

对直接式和间接式低温地热供热系统的设计与质调节问题进行了分析和讨论，给出了不同室外温度条件下的混水比例的计算方法和公式，为低温地热供热系统的优化设计和控制提供了理论依据。     

换热器设计计算及报价的计算机辅助系统

以光滑管换热器、片状管换热器及管状插入件换热器为例，开发了一个计算机辅助计算及报价的软件系统。运用该软件比较了三种换热器在相同设计条件下的设计计算结果，以及它们的制造成本和销售价格，结果表明该系统可减轻设计者的劳动强度，提高工作效率，为换热器的设计选型提供了依据。     

回转窑式废弃物焚烧炉的设计

分析了各工业废弃物的燃烧特征，给出了焚烧系统的设计思路以及重要设备的计算方法，并在实际中得到检验。图2表1参3     

VSBK竖井节能砖窑的设计计算

本文应用燃烧学和传热学的基本理论，在大量试验的基础上，提出了ＶＳＢＫ竖井节能砖窑的设计计算方法，并给出了计算实例，最后评价了该设计计算方法。     

Stretched tape design of fixed mirror solar concentrator with curved mirror elements

The optical design of a fixed mirror line-focus solar concentrator, using curved mirror elements whose radius of curvature is matched to the radius of the reference cylinder of the concentrator, is presented. It is shown that this design leads to a considerable decrease in the transverse width of the focal intensity profile as compared with a fixed mirror solar concentrator of similar design made of flat mirror elements, and thus enables reduction in the cost of the heat receiver assembly. The development of a stretched tape construction of a 12 m × 3 m fixed mirror solar concentrator, conforming to the above design by using cold rolled steel tapes with constant levels of curvature across their width as substrates for the curved mirror elements, is briefly reported. Results from optical tests on the concentrator, which confirm the predictions from the theoretical model of the optics of the concentrator, are presented.     

Static solar concentrator with vertical flat plate photovoltaic cells and switchable white/transparent bottom plate

A new type of static solar concentrator is proposed to match the aesthetic features of towns. The concentrator consists of vertical plate solar cells and white/transparent switchable bottom plate, which is operated with external power. The bottom is switched to be a diffuse reflection white surface when the cell generates electric power, and switched to be a light transmissible transparent surface when the cell does not deliver power. The light collection of this concentrator was analyzed by using multiple total internal reflection model and ray tracing simulation. For the same ratio of the area of the solar cells to that of the collector surface, the collection efficiency for the proposed concentrator is about half of that of the conventional concentrator for flat plate cell, and nearly equal to that of the concentrator for the embedded spherical silicon solar cells.     

A 100-sun linear photovoltaic solar concentrator design from inexpensive commercial components

The optical design for a high-efficiency linear photovoltaic solar concentrator assembled from readily-available inexpensive components is presented. Accounting for all geometric and material-related optical losses, we find that it should easily produce flux levels of 50–100 suns with homogeneous irradiance of the absorber. This is well suited to the peak-performance point of concentrator solar cells.     

Thermal performance of solar concentrator/cavity receiver systems

To utilize solar energy at a high temperature, a parabolic dish/cavity receiver configuration is often used. The energy loss mechanisms of such a system are analyzed. System efficiency is defined as the power absorbed by the working fluid circulating in the cavity divided by the solar power falling on the concentrator aperture. Power profiles produced in cavities of varying geometry with concentrators of varying rim angle are also discussed. It is found that varying concentrator rim angle and cavity geometry can greatly affect the cavity power profile without a large effect on system efficiency. Cavity isothermality often requires a nonlinear power profile , particularly in a thermochemical system. The methodology described can be used to optimize concentrator/cavity design variables.     

Some geometrical design aspects of a linear fresnel reflector concentrator

A somewhat new approach to the design of solar concentrators of Fresnel reflector geometry is outlined. the constituent mirror elements of the concentrator surface are characterised by three parameters, shift, tilt and width. the evaluation of these parameters and the concentration characteristics are investigated on the basis of a simple ray optical model.     

Thermal design of parabolic solar concentrator adsorption refrigeration system

This study presents a thermal design of solar-powered adsorption refrigeration with the type of activated carbon-methanol pair. The designed module consists of an evacuated glass tube equipped with a parabolic solar concentrator as generator, sorption bed, evaporator, and condenser units. A thermodynamic design procedure and a mathematical model of a steady state system with activated carbon refrigerator have been developed. The adsorber is heated by solar energy collected by a parabolic solar concentrator. The temperature of the working pair in the adsorber, the amount of methanol leaving and reabsorb bed, and the refrigerated box was estimated. An optimize design of the system to achieve higher cycle COP was presented. Maximum cycle COP = 0.576 and COP_net = 0.375 with T _max reached 157.8°C, T _B = 57.5°C, M _ac = 0.907 kg, and the concentration of methanoldesorped equal to 0.206 kg/kg _ac .     

Design and fabrication of low concentrating second generation PRIDE concentrator

Prototype first generation Photovoltaic Facades of Reduced Costs Incorporating Devices with Optically Concentrating Elements (PRIDE) technology incorporating 3 and 9 mm wide single crystal silicon solar cells showed excellent power output compared to a similar non-concentrating system when it was characterized both indoors using a flash and continuous solar simulator. However, durability and instability of the dielectric material occurred in long-term characterisation when the concentrator was made by using casting technology. For large scale manufacturing process, durability, and to reduce the weight of the concentrator, second generation PRIDE design incorporated 6 mm wide “Saturn” solar cells at the absorber of dielectric concentrators. Injection moulding was used to manufacture 3 kWp of such PV concentrator module for building façade integration in Europe. Special design techniques and cost implications are implemented in this paper. A randomly selected PV concentrator was characterised at outdoors from twenty-four (≈3 kWp) 2nd-G PRIDE manufactured concentrators. The initial PV concentrators achieved a power ratio of 2.01 when compared to a similar non-concentrating system. The solar to electrical conversion efficiency achieved for the PV panel was 10.2% when characterised outdoors. In large scale manufacturing process, cost reduction of 40% is achievable using this concentrator manufacturing technology.     

Upper bounds for the yearly energy delivery of stationary solar concentrators and the implications for concentrator optical design

Compound parabolic concentrator (CPC) type collectors have been viewed as the optimal design for totally stationary concentrators. However the CPC is ideal only for uniform incident solar flux averaged over the energy collection period. The actual yearly-averaged incident flux map turns out to be highly non-uniform, as a function of projected incidence angle, which implies that concentration can be increased markedly if optical collection efficiency is compromised. The question then becomes: what concentrator angular acceptance function is best matched to nature's radiation flux input, and how much energy can such a concentrator deliver? The recently-invented tailored edge-ray concentrator (TERC) approach could be used to determine optimal reflector contours, given the optimal acceptance angle function. We demonstrate that totally stationary TERCs can have around three times the geometric concentration of corresponding optimized stationary CPCs, with greater energy delivery per absorber area, in particular for applications that are currently being considered for stationary evacuated concentrators with the latest low-emissivity selective coatings, e.g. solar-driven double-stage absorption chillers (at around 170°C) and solar thermal power generation (at around 250°C).     

A novel PVT/PTC/ORC solar power system with PV totally immersed in transparent organic fluid

A novel hybrid PVT/parabolic trough concentrator (PTC)/organic Rankine cycle (ORC) solar power system integrated with underground heat exchanger has been proposed. The evaporator unit consists of a transparent flat PVT solar collector and a PTC connected in series. The first transparent solar collector has transparent covers and consists of solar cells totally immersed within a pressurized transparent organic fluid that allows the solar radiation to reach the solar cells, cools them effectively, and captures all thermal losses from the solar cells. The second concentrator is a conventional one with opaque black receiver used to reheat the transparent organic fluid to higher temperatures. Both solar collectors (the PVT and PTC) perform as the boiler and superheater for the ORC. The performance of the proposed system is investigated by a steady‐state mathematical model. The results show that, at design conditions, the efficiency of the PV modules stabilizes around 12%, absorber efficiency varies within 64% to 75%, and the ORC efficiency varies within 7% to 17%.     

Thermodynamic optimisation of the integrated design of a small‐scale solar thermal Brayton cycle

The Brayton cycle's heat source does not need to be from combustion but can be extracted from solar energy. When a black cavity receiver is mounted at the focus of a parabolic dish concentrator, the reflected light is absorbed and converted into a heat source. The second law of thermodynamics and entropy generation minimisation are applied to optimise the geometries of the recuperator and receiver. The irreversibilities in the recuperative solar thermal Brayton cycle are mainly due to heat transfer across a finite temperature difference and fluid friction. In a small‐scale open and direct solar thermal Brayton cycle with a micro‐turbine operating at its highest compressor efficiency, the geometries of a cavity receiver and counterflow‐plated recuperator can be optimised in such a way that the system produces maximum net power output. A modified cavity receiver is used in the analysis, and parabolic dish concentrator diameters of 6 to 18 m are considered. Two cavity construction methods are compared. Results show that the maximum thermal efficiency of the system is a function of the solar concentrator diameter and choice of micro‐turbine. The optimum receiver tube diameter is relatively large when compared with the receiver size. The optimum recuperator channel aspect ratio for the highest maximum net power output of a micro‐turbine is a linear function of the system mass flow rate for a constant recuperator height. For a system operating at a relatively small mass flow rate, with a specific concentrator size, the optimum recuperator length is small. For the systems with the highest maximum net power output, the irreversibilities are spread throughout the system in such a way that the internal irreversibility rate is almost three times the external irreversibility rate. Copyright © 2011 John Wiley & Sons, Ltd.