Li Z.,Tianjin University |
Li W.,Tianjin University |
Xu B.,China Aviation Planning and Construction Development Co.
Applied Thermal Engineering
A novel combined cooling, heating and powerorganic Rankine cycle (CCHP-ORC) system installed with heat pumps is presented in this paper. The CCHP-ORC system using zeotropic mixtures is first discussed, and this work is focused on selecting optimal zeotropic mixtures and determining the component concentration that gives a better performance. A system model under an idealized operating condition was built. The heat source is geothermal water whose temperature is 95 °C, and the mass flow is 40 t/h. The heat transfer fluid is heated to 45 °C for heating with the ambient temperature of -5 °C, and the refrigerating fluid is cooled to 0 °C with the ambient temperature of 35 °C. In this paper, 20 zeotropic mixtures were analyzed. The evaluation index net output power, heating capacity, refrigerating capacity, coefficient of performance (COP), economic thermal efficiency and exergy efficiency were calculated with the changing evaporation temperature under the condition of ejector coefficient 0.2. The ejector coefficient and evaporation temperature had been analyzed as independent variables. The results showed that R141b/R134a, R141b/R152a and R123/152a have a higher COP and exergy efficiency than others. By analyzing the component concentration of the optimized three kinds of zeotropic mixtures, it can be inferred that a mixture of dry and wet working fluids is more suitable for the system. The system gives rise to higher energy output if zeotropic mixtures are made of a higher proportion of wet working fluid and a lower proportion of dry working fluid. © 2015 Published by Elsevier Ltd. Source
Liang S.,Zhejiang University |
Nan X.,Zhejiang University |
Yi W.,China Aviation Planning and Construction Development Co.
Journal of Earthquake Engineering and Engineering Vibration
The equivalent linearization method approximates the maximum displacement response of nonlinear structures through the corresponding equivalent linear system. By using the particle swarm optimization technique, a new statistical approach is developed to determine the key parameters of such an equivalent linear system over a 2D space of period and damping ratio. The new optimization criterion realizes the consideration of the structural safety margin in the equivalent linearization method when applied to the performance-based seismic design/evaluation of engineering structures. As an application, equations for equivalent system parameters of both bilinear hysteretic and stiffness degrading single-degree-of-freedom systems are deduced with the assumption of a constant ductility ratio. Error analyses are also performed to validate the proposed approach. Source
Zhang Q.,China Aviation Planning and Construction Development Co.
Yantu Gongcheng Xuebao/Chinese Journal of Geotechnical Engineering
A highrise building is characterized by large column grid. Central column load is much greater than side column load. In order to reduce the differential settlement between central column and side column, the optimization design of pile foundation considering variable rigidity is adopted. With central column pile 800 mm in diameter and 40 m in length and the side column pile 600 mm in diameter and 25 m in length, differential settlement problem is solved. Source
China Aviation Planning and Construction Development Co. | Date: 2014-09-29
A method of designing a cable dome structure based on a cable dome bearing whole process analysis. The cable dome bearing whole process has three stages comprising a ridge cable relaxation, a ring cable yield and a structure failure.
China Aviation Planning and Construction Development Co. | Date: 2013-06-18
A cable-membrane tensegrity structure which is asymmetric, and construction method and design method thereof are provided. The cable-membrane tensegrity structure comprises a central opening and is formed by a ring cable (