The Experts below are selected from a list of 2067 Experts worldwide ranked by ideXlab platform

Zhu Dong-sheng - One of the best experts on this subject based on the ideXlab platform.

  • Design Optimization of Evaporative Condenser
    Fluid Machinery, 2011
    Co-Authors: Zhu Dong-sheng
    Abstract:

    The maximum heat transfer coefficient was present as the objective function,total heat exchange quantity and air-side pressure drop as constraint conditions,plate space Sa,height of plate H and length of Evaporative Condenser L as variables to optimize,composing the structural optimization process and providing reference to engineering design.The results show that suitable choise are plate spacing 11 ～ 22.5mm,plate height 0.7 ～ 1.6m,length more than 7m;when L = 8m,Sa = 22mm,H = 0.8m the heat transfer coefficient becomes the max of 578.3W /(m2.℃);when the the heat transfer cooefficient is constant,the sensitivity of coefficient is L H Sa。

  • Experimental Study on Water Film Flow Characteristics of Vertical Evaporative Condenser
    Fluid Machinery, 2010
    Co-Authors: Zhu Dong-sheng
    Abstract:

    The water film flow characteristics of vertical Evaporative Condenser were studied.The influences of water mass flux and air inlet velocity and spiral insert on water flow characteristics of this type Evaporative Condenser were investigated.Finally,phenomena of flooding was discussed and flooding empirical formula was proposed.These conclusions are useful for the design and optimization of this type of Evaporative Condenser.

  • Thermal characteristics of plate-type Evaporative Condenser
    Chemical Industry and Engineering Progress, 2009
    Co-Authors: Zhu Dong-sheng
    Abstract:

    Experimental studies on major factors affecting thermal characteristics of the plate-type Evaporative Condenser,i.e.,air wet-bulb temperature,condensation temperature and relative moisture were conducted.The results showed that condensation temperature and condensation pressure increased with increasing inlet air wet-bulb temperature.Compressor power consumption was greatly affected by inlet air relative humidity and wet-bulb temperature.Comparisons based on the same vapor-compression refrigeration unit showed that the heat flux of the plate-type Evaporative Condenser was larger by 30.5% than the tube-type Evaporative Condenser when the condensation temperature was 38℃.The lower the inlet air wet-bulb temperature,the larger the difference between the heat stream density of the plate-type Evaporative Condenser and the tube-type Evaporative Condenser at the same condensation temperature.

  • Characters and Industrial Application of the Evaporative Condenser with Twisted Tube
    Fluid Machinery, 2008
    Co-Authors: Zhu Dong-sheng
    Abstract:

    To enhance the heat transfer and flow processes,the twisted tube was used in the Evaporative Condenser,and compared the existing round-tube.An experimental system was established,heat transfer coefficient and power performance characters of the Evaporative Condenser with variational geometry sizes were investigated with variational fluid parameters.The results indicate that the characters of twisted tubes are better than round tubes,and the heat transfer coefficient and power characters are increased with the diminishment of geometry sizes and the increase of fluid parameters.Finally,the Evaporative Condenser was used in the industry and energy and water saving were obvious.

  • Research progress on hot-dip galvanizing of Evaporative Condenser coils
    Electroplating & Finishing, 2006
    Co-Authors: Zhu Dong-sheng
    Abstract:

    Evaporative Condenser is a kind of effective and energy-saving heat exchange equipment,whose basic unit is heat exchange coil.The corrosion problem of heat exchange coil has become the key factor restricting the progress of Evaporative Condenser.The research status of hot dipping galvanizing for Evaporative Condenser coil and its mechanism were reviewed.Some problems existing in hot-dip galvanizing for Evaporative Condenser coil were presented and suggestions on further research in the field were put forward.

Qinggang Qiu - One of the best experts on this subject based on the ideXlab platform.

  • experimental study on the heat and mass transfer characteristics of air water two phase flow in an Evaporative Condenser with a horizontal elliptical tube bundle
    Applied Thermal Engineering, 2020
    Co-Authors: Xiaojing Zhu, Shi Chen, Shengqiang Shen, Xu Shi, Qinggang Qiu
    Abstract:

    Abstract In this paper, the heat and mass transfer performance of an Evaporative Condenser with a horizontal elliptical tube bundlewasexperimentally studied. The effects of important parameters, such as the spray density, frontal air velocity, ambient temperature and humidity, on the heat and mass transfer performance were discussed in detail. Among all parameters studied, it was found that the wet bulb temperature has greater effects on the heat transfer performance than the relative humidity. Thedifference between the steamtemperature and tube wall temperature, the inlet steam flow rate and the steam saturation temperature all affect the mean within-tube condensation heat transfer coefficient. Themeanwithin-tube condensation heat transfer coefficientincreases greatly when the latter two increase, while the increase in the difference between steam and tube wall temperature hinders the mean within-tube condensation heat transfer coefficient. The empirical correlations of the mean within-tube condensation heat transfer coefficient, wall-film convective heat transfer coefficient and the film-air convective mass transfer coefficient were finally obtained by regression fitting the experimental data using the least square method and all empirical correlations have enough precision in engineering calculation.

Wang Changhong - One of the best experts on this subject based on the ideXlab platform.

  • effect of special shape steel tubes on the heat transfer performance of the Evaporative Condenser
    Journal of Chemical Engineering of Chinese Universities, 2009
    Co-Authors: Wang Changhong
    Abstract:

    Evaporative Condenser(EC)is a type of effective cooling equipment and a comprehensive study on its heat transfer performance is needed at present.Base on the understanding of the heat transfer characteristics of EC,three types of special-shaped steel heat exchange tubes(bullet-tube,twisted tube and bullet-twisted tube) were contrived respectively to enhance the heat transfer process in the EC.The fluid flow and heat transfer performances of the EC consisted of the above special-shaped steel heat exchange tubes separately were investigated and compared with those of the EC consisted of the conventional rounded tube and elliptical tube. The results indicate that,when the spraying density of water is 0.06 kg m-1·s-1 and airflow velocity is 3.4 m·s-1,the total heat transfer coefficients of the EC consisted of ellipse-tube,bullet-tube,twisted-tube and bullet-twisted tube are respectively 19.2%,24.4%,26.8%and 31.2%higher than that of the EC consisted of round-tube.The use of bullet-tube can enhance the heat transfer between water and air and decrease the pressure drop of the airflow.The use of twisted-tube can enhance the heat transfer of water film but will increase the pressure drop of the airflow.The use of bullet-twisted-tube can improve both the heat transfer processes of water film and airflow.

  • performance and industrial application of Evaporative Condenser with special shape steel tubes
    Chemical Industry and Engineering Progress, 2008
    Co-Authors: Wang Changhong
    Abstract:

    To enhance the heat transfer and flow,both special-shape tubes including bullet-tube and twist-tube were used in the Evaporative Condenser,and compared with the existing round-tube.An experimental system wasset up,heat transfer coefficient and power performance of the Evaporative Condenser were investigated with changing operation parameters.The results indicated that heat transfer coefficient and power performance were better when the sprayed water flow rate ranged 0.05—0.065 kg/(m.s) and airflow velocity ranged 2.6—3.4 m/s.The heat transfer coefficient of the bullet-tube was 9.2%—19.0% higher than that of round-tube,while the power decreased by 2.6%—4.9%.The heat transfer coefficient of the twist-tube was 18.0%—33.1% higher than that of round-tube,and the power increased by 2.6%—4.9%.Finally,the two new types of Evaporative Condenser were used in industry with obvious energy and water saving.

Jiang Xiang - One of the best experts on this subject based on the ideXlab platform.

  • Two-Phase Flow Simulation of Heat Exchanger of Wet Enthalpy Recycling Energy-Saving Fresh Air Condition
    Journal of Engineering Thermophysics, 2012
    Co-Authors: Zhu Dongsheng, Ou Zhijiang, Jiang Xiang
    Abstract:

    This paper focus on wet enthalpy recycling energy-saving fresh air condition.Established a computational model of corrugated plate Evaporative Condenser base on the volume of fluid(VOF) method.Using this model,this paper simulated and analyzed the influence factors of the plate heat transfer performance,such as heat flux density,water inlet temperature,water spray,gas inlet velocity and plate spacing.Results show that:the effects of heat flux on the wall temperature and gas-liquid interface temperature is linear;in the same heat flux,the interface temperature be reduced accordingly with the spray density increases;increasing gas flow rate or reducing the plate space can play the role of enhancing heat transfer.

  • Application and Appraise of Air Conditioning System with Enhanced Heat Transfer Tube Evaporative Condenser
    Mechanical & Electrical Engineering Technology, 2011
    Co-Authors: Jiang Xiang
    Abstract:

    To appease energy and water saving,lower noise and integration of buildings,we substitute the Evaporative Condenser for water-cooled Condenser in an air-conditioning system in this paper.The characters of three types of air-conditioning system with the Evaporative Condenser and water-cooled Condenser were compared.The results indicate the energy efficiency ratio of Evaporative condensing air conditioning is 15.2% better than the water condensing air conditionings.Furthermore,the volume of new Evaporative condensing air conditioning system is lower than water-cooled system,it can be placed in the basement and do not affect the appearance of buildings and reduce noise.But as a new equipment,the design,the Evaporative condensing air conditioning.

  • STUDY ON HEAT TRANSFER CHARACTERISTICS IN A VERTICAL TUBE Evaporative Condenser
    Journal of Shaanxi University of Science & Technology, 2007
    Co-Authors: Jiang Xiang
    Abstract:

    Evaporative cooling is used to reduce temperature in different fluids in industrial and air conditioning processes.The processes of coolers involve two phase flow between air and water,the heat-mass transfer and its coupled process.In this study,the heat transfer characteristics in a vertical tube Evaporative Condenser have been investigated.A steady-state,one-dimensional model of cooler performance is formulated.The heat resistance at the air-water interface predominates over all other heat resistance.With the enhanced experiment of the spring inserts,the heat transfer characteristics might be increased greatly.These findings may provide more information to the design of vertical-tube Evaporative Condensers.

Murat Hosoz - One of the best experts on this subject based on the ideXlab platform.

  • comparative analysis of an Evaporative Condenser using artificial neural network and adaptive neuro fuzzy inference system
    International Journal of Refrigeration-revue Internationale Du Froid, 2008
    Co-Authors: Metin H Ertunc, Murat Hosoz
    Abstract:

    This study deals with predicting the performance of an Evaporative Condenser using both artificial neural network (ANN) and adaptive neuro-fuzzy inference system (ANFIS) techniques. For this aim, an experimental Evaporative Condenser consisting of a copper tube condensing coil along with air and water circuit elements was developed and equipped with instruments used for temperature, pressure and flow rate measurements. After the Condenser was connected to an R134a vapour-compression refrigeration circuit, it was operated at steady state conditions, while varying both dry and wet bulb temperatures of the air stream entering the Condenser, air and water flow rates as well as pressure, temperature and flow rate of the entering refrigerant. Using some of the experimental data for training, ANN and ANFIS models for the Evaporative Condenser were developed. These models were used for predicting the Condenser heat rejection rate, refrigerant temperature leaving the Condenser along with dry and wet bulb temperatures of the leaving air stream. Although it was observed that both ANN and ANFIS models yielded a good statistical prediction performance in terms of correlation coefficient, mean relative error, root mean square error and absolute fraction of variance, the accuracies of ANFIS predictions were usually slightly better than those of ANN predictions. This study reveals that, having an extended prediction capability compared to ANN, the ANFIS technique can also be used for predicting the performance of Evaporative Condensers.

  • Artificial neural network analysis of a refrigeration system with an Evaporative Condenser
    Applied Thermal Engineering, 2006
    Co-Authors: Huseyin Metin Ertunc, Murat Hosoz
    Abstract:

    Abstract This paper describes an application of artificial neural networks (ANNs) to predict the performance of a refrigeration system with an Evaporative Condenser. In order to gather data for training and testing the proposed ANN, an experimental refrigeration system with an Evaporative Condenser was set up. Then, steady-state test runs were conducted varying the evaporator load, air and water flow rates passing through the Condenser and both dry and wet bulb temperatures of the air stream entering the Condenser. Utilizing some of the experimental data, an ANN model for the system based on standard backpropagation algorithm was developed. The ANN was used for predicting various performance parameters of the system, namely the Condenser heat rejection rate, refrigerant mass flow rate, compressor power, electric power input to the compressor motor and the coefficient of performance. The ANN predictions usually agree well with the experimental values with correlation coefficients in the range of 0.933–1.000, mean relative errors in the range of 1.90–4.18% and very low root mean square errors. Results show that refrigeration systems, even complex ones involving concurrent heat and mass transfer such as systems with an Evaporative Condenser, can alternatively be modelled using ANNs within a high degree of accuracy.

  • Performance evaluations of refrigeration systems with air‐cooled, water‐cooled and Evaporative Condensers
    International Journal of Energy Research, 2004
    Co-Authors: Murat Hosoz, Ali Kilicarslan
    Abstract:

    This paper compares the performance characteristics of refrigeration systems employing three types of Condensers, namely the air-cooled, the water-cooled and the Evaporative Condensers. Experimental studies were conducted in the same vapour-compression refrigeration unit operating with a different Condenser in each test. It was found that the system with water-cooled Condenser had a higher refrigeration capacity by 2.9–14.4%, and a higher COP by 1.5–10.2% than the one with Evaporative Condenser. However, the refrigeration capacity and COP of the unit with Evaporative Condenser were higher than those of the one with air-cooled Condenser by 31.0 and 14.3%, respectively. Copyright © 2004 John Wiley & Sons, Ltd.