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The asymptotic formula is obtained for the capacity of a generalized condenser when parts of its plates contract to prescribed points. In contrast to the previous studies of capacity, we consider condensers with variable potential levels and establish the third term of the asymptotics. [ABSTRACT FROM AUTHOR]

An example of assessment of condenser casing strength taking account of extending the casing life 30 years beyond the design life is discussed. [ABSTRACT FROM AUTHOR]

This paper tackles an optimization approach in order to boost the fresh water production of a new design of a solar still which is located at Sfax engineering national school in Tunisia. This optimization approach is based upon the above mentioned design's improvement by coupling the conventional solar still into at a condenser, solar air and water collector and humidifier. This new concept of a distiller solar still using humidification- dehumidification processes (HD) is exploited for the desalination purpose. As a result of this work, the humidification- dehumidification processes have an essential effect in improving the solar still performance. Performance has been predicted theoretically in terms of water and inner glass cover temperatures, the inlet temperature of air and water of the new concept of distiller on water condensation rate and fresh water production. A general model based on heat and mass transfers in each component of the unit has been developed in steady dynamic regime. The developed model is used, simulating the HD system, to investigate the influence of the meteorological and operating parameters on the system productivity. The obtained set of ordinary differential equations has been converted to a set of algebraic system of equations by the functional approximation method of orthogonal collocation. The developed model is used to simulate the HD system in order to investigate the steady state behavior of each component of the unit and the entire system exposed to a variation of the entrance parameters and meteorological conditions. The obtained results were compared with those of other studies and the comparison gives a good validity of the present results. [ABSTRACT FROM AUTHOR]

Corrosion and scaling of heat exchanger is a severe problem in oil refinery industries. In this paper, the corrosion mechanisms of tubes in the condenser at the top of the benzene tower have been investigated by elemental analyzer, optical microscopy, and scanning electron microscopy (SEM) with energy-dispersive spectrometry (EDS) and X-ray diffraction (XRD) analysis. It is concluded that corrosion occurred outside the tube due to a trace amount of acidic water containing chloride ion which condensed on the surface of tubes. Then the condensed acidic water led to electrochemical corrosion during heat exchanging process in the condenser at the top of the tower. Chloride ion plays a very important role in the tube corrosion. The most important point is that chloride ion could cause the depassivation of material. Moreover, chloride ion is easily absorbed onto the surface of tubes due to the negative charge. Later, the corrosion of tubes is accelerated due to ion migration if the concentration of chloride ion increases. In addition, the loose scales of corrosion product also accelerate the electrochemical corrosion since it makes the acidic aqueous solution easier to stay and concentrate on the tube surface. [ABSTRACT FROM AUTHOR]

The aim of the present research is the development of a computational tool for investigating condensation processes and equipment with particular attention to freeze-dryers. These condensers in fact are usually operated at very low pressures, making it difficult to experimentally acquire quantitative knowledge of all the variables involved. Mathematical modelling and CFD (Computational Fluid Dynamics) simulations are used here to achieve a better comprehension of the flow dynamics and of the process of ice condensation and deposition in the condenser, in order to evaluate condenser efficiency and gain deeper insights of the process to be used for the improvement of its design. Both a complete laboratory-scale freeze-drying apparatus and an industrial-scale condenser have been investigated in this work, modelling the process of water vapour deposition. Different operating conditions have been considered and the influence exerted by the inert gas as well as other parameters has been investigated. [ABSTRACT FROM AUTHOR]