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1.
Temperature control offers benefits in land‐based marine aquaculture: stock growth rates may be enhanced by heating in winter; mortality rates in summer may be reduced by cooling. However, if the plant is not well designed, temperature control may create very large energy demands. This paper describes the application of temperature control in abalone aquaculture in New Zealand, with a focus on energy considerations in plant design. An abalone farm using a semi‐closed water conditioning system is used as a case study for which an energy model, based on a heat pump system, is developed. The model is used to determine the impact of plant design and tank conditions on the economics of the operation. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
2.
The paper describes the integration of a chemical and a vapour-compression heat pump for energy storage applications. The vapour-compression system is designed to operate using the UK cheap rate ‘Economy 7’ electricity tariff. The system is characterized thermodynamically using various refrigerant/absorbent pairs in the chemical storage circuit and an ozone-friendly refrigerant, R134a, in the vapour-compression circuit. Results indicate that the H2O/Na2S pair provides a high energy storage density and is the most suitable for use in this system. The paper also describes the design features of a domestic-sized version of this heat pump system. Air in the sunspace (conservatory) of a house was used as a heat source for the heat pump. 相似文献
3.
针对YLJ型液环式氯气泵叶轮在短期内频繁破碎的情况,对其破碎原因进行了分析,并提出相应的改进措施,使烧碱工艺系统保持了长、满、安、稳的运行状态。 相似文献
4.
Calculation methods for comparing the performance of pure and mixed working fluids in heat pump applications 总被引:2,自引:0,他引:2
Three methods for comparing cycle performance of working fluids, pure as well as non-azeotropic mixtures, are investigated for two applications and for two mixture pairs, HCFC22-CFC114 and HCFC22-HCFC142b, and their pure components. The methods differ in the way of calculating the heat exchange processes. They assume, respectively, equal minimum approach temperatures, equal mean temperature differences and equal heat transfer areas. Changes of coefficient of performance (COP) with composition are explained for all methods. It is shown that transport properties must be taken into account when making rigorous comparisons between working fluids. To predict the relations between fluids with high accuracy, one must use the method with equal heat transfer areas. By the method with equal mean temperature differences, the COP can be estimated with the same accuracy for mixtures as for pure fluids, and can be used for rough estimations of the COP level with different fluids. The method of equal minimum approach temperatures should be avoided for non-azeotropic mixtures. 相似文献
5.
Cui Gui-xiang Xu Wei-ran Department of Engineering Mechanics Tsinghua University Beijing P.R.China 《水动力学研究与进展(B辑)》1993,(4)
This paper presents a numerical method for simulation of the flow and thecalculated results of the quasi-steady axisymmetrical flow field and pressure distribution on valveball with power-law model for Non-Newtonian fluid in suck-rod pump.We believe the methodcan provide a foundation for further research and improvement of the design of suck-rod pump. 相似文献
6.
O. J. Svec 《国际能源研究杂志》1987,11(4):573-581
This paper presents a historical background of ground source heat pump technology, followed by a review of its current shortcomings. Based on these observations the author assesses the R&D needs and recommendations for future research. 相似文献
7.
随着我国经济的迅速发展,能源消耗不断增加,节约能源、降低能源消耗势在必行,余热利用是节约能源的一个重要环节,冶金行业高炉冲渣水作为采暖热媒可以节约大量能源。 相似文献
8.
9.
本文简要阐述了北化院BCS01和上海院SLC-S两种国产气相聚乙烯浆液催化剂的性能、催化剂结构,在Unipol聚乙烯工业装置上应用结果,以及和进口同类催化剂UCAT-J的性能比较。 相似文献
10.