In this paper, a special lifetime testing apparatus is installed for dropwise condensation heat transfer on polymer-coated surfaces. Film and dropwise condensations are simultaneously carried out in the same condensing chamber to get rid of any containments. The discontinuous experimental results demonstrate that one surface has sustained dropwise condensation for about 1000 hours. The condensation heat transfer characteristics tend toward stability. In addition, the experiments prove that a polymer film prepared by the dynamic ion-beam mixed implantation (DIMI) method has good adhesion with the metal substrate.

The forces acting on a microcarrier or a small piece of tissue and its movement in the rotating wall vessel (RWV) bioreactor were analyzed. The tracks of a particle in RWV reactor were calculated under different inner and outer cylinder wall rotating speeds, different particle sizes and different density difference between culture medium and the particle. The results show that cells or particles experience partial microgravity only in the upper area ofRWV, which changes with angle θ, while in the lower part ofRWV, they experience overweight. The trajectory of a moving particle in RWV reactor is an eccentric helix under ground-based condition. And the eccentric degree increases with the decrease of outer wall rotating speed, and with the increase of density difference and particle size. The proper match of rotating speeds of inner and outer cylinder walls is the key to prevent the particle colliding with the walls. For a relatively large piece of cultivated tissue, it can move around the inner wall only when the rotating speed of the outer cylinder is high. And the drag force acting on a particle inside RWV increases with the particle size and the density difference.

The plasma polymerization method and dynamic ion-beam mixed implantation method were employed to coat ultra-thin polymer films on copper plates. Experiments indicated that steady dropwise condensation of steam at atmospheric pressure occurred. The condensation heat transfer coefficients increased by approximately 3 and 5-7 times for the polytrimethylvinylsilane film and polytetrafluoroethylene film respectively, compared with the value for film condensation under the same experimental conditions. The temperatures on the condensing surface and inside the test block were found to be rapidly and randomly fluctuated. The properties of the coated films and advantages of the methods used in this investigation were discussed briefly.

This paper reports the test results of the first industrial-scale absorption heat transformer (AHT) equipment in China, to recover the waste heat released from mixture of steam and organic vapor at 98 C in coacervation section, synthetic rubber plant of Yanshan Petrochemical Corporation, Beijing, China. The recovered heat is used to heat hot water from 95 to 110 C, feeding back to the coagulator as the supplementary heating source. The AHT system is operating with H2O/LiBr solution with heat flow of 5000kW. The coefficient of performance (COP), the thermal efficiency and the temperature lift of the AHT system are presented. The heat transfer characteristics of the AHT components, i.e. absorber, generator, evaporator, condenser and the liquid-liquid solution heat exchanger, are also illustrated by comparison of experimental data and the model calculated results. The results show that the mean COP is 0.47, the gross temperature lift of 25 C can be realized and the payback period is 2 years.

The effect of processing conditions of polymer film on dropwise condensation heat transfer of steam under atmo-spheric pressure is investigated to find an effective technique to prepare a viable polymer film sustaining long-term dropwise condensation pattern state. The polytetrafluoroethylene (PTFE) films were coated on the external surfaces of brass tubes, copper tube, stainless steel tube and carbon steel tube by means of the dynamic ion-beam mixed implantation technique, with a variety of surface processing conditions. The experimental results indicated that heat flux is increased by 0:3-4:6 times and condensation heat transfer coefficient by 1:6-28:6 times of film condensation values for the brass tubes treated with various conditions. The surface processing condition is crucial to the adhesion between polymer film and metal substrate, different substrate material requires different optimal processing condition, and leads to different condensation heat transfer characteristic.