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The desiccant rotor is the most essential component of desiccant cooling system, but one of its drawbacks to spread out is its rotor size. To reduce the size of rotor the analysis of rotor performance is crucial. Systematic examination on the effect of desiccant and channel geometrics has been conducted based on the numerical program previously developed. Considered parameters related to channel geometrics are channel shape and cross-section area of channel, and parameters related to desiccant are mass fraction, heat capacity, density, maximum water uptake and separation factor of isotherm. Considerable reduction of rotor size is expected by adjusting the parameters.

Warp-around heat pipes (WAHP) belong to a special class of recuperative heat exchangers that transfer heat from inlet to outlet locations via thermal gradient, without using any energy. In the present work, effects of various mechanical parameters on the performance of a WAHP dehumidifier system that are based on the underlying principles of heat and mass conservation are presented primarily from a theoretical point of view. A simplified methodology pertaining to wet cooling coils is applied here for defining the case of moisture condensation during precooling process at WAHP evaporator. Inlet air temperature, inlet humidity ratio, air mass flow rate, dehumidifier outlet temperature and effectiveness are the main operational parameters considered in this study. On the other hand, comparative performance study of the WAHP system is done through an other set of thermodynamic parameters like the supply air temperature, supply humidity ratio, specific coil load and recovered enthalpy. The subtle variations in these factors against the operational parameters not only help in stipulating functional characteristics of the WAHP but also allow HVAC designers to make informed decisions for system design and performance without relying entirely on manufacturer’s equipment data.

Desiccant cooling mechanism is one of the alternate methods to control the humidity of air and temperature, compared to the conventional vapor compression method of air conditioning. Desiccant cooling doesn’t use harmful chemicals which effect the ozone layer and it saves lots of energy. Summer air condition system can use this technology since it removes the latent heat load from the room effectively and this process is economical. Selection of the appropriate liquid desiccant and packing material is very vital to obtain maximum dehumidification. This paper focuses on the different desiccants and packings used by different researchers to enhance the dehumidification. Simple and hybrid systems are also reviewed, and their comparison are presented based on the construction and dehumidification performance.

Air conditioning is one of the large energy consuming sectors, as it comforts the human in closed environment. Especially, in coastal regions where both temperature and humidity are high, it demands for air conditioning. Usually, in such cases, cooling and dehumidification of outside air is done by cooling coils. Such cooling and dehumidification coils requires relatively large amount of energy. In the era of energy saving technologies, Liquid desiccant system (LDS) has proved to be one of the best alternatives for controlling the humidity, economically and efficiently. Different liquid desiccants are available for dehumidification purpose with their own advantages and disadvantages. This paper summarizes the different liquid desiccants used by researchers in their study and the performances analysis of dehumidification process. An attempt is also made to summarize the characteristics of the different hybrid or composite desiccants developed by researchers in order to improve the desiccant properties for the better dehumidification process.

A Turbine Inlet Air Conditioning (TIAC) system can chill the inlet air of the turbine to maintain maximum turbine performance at all ambient temperatures. However, turbine characteristics, performance guarantees and bell-mouth icing considerations require accurate prediction of the chilling coil performance over a wide range of operating conditions. A modified wet-surface model (MWSM) is developed to more accurately predict the chilling coil performance. The higher accuracy of the model is demonstrated by applying the model to simulate performance data of two different coils. The data covered a wide range of operating conditions with ambient temperature vary from $43.3^{\circ }$C to $9.7^{\circ }$C dry bulb and $27.2^{\circ }$C to $6.1^{\circ }$C wet bulb. The turbine flow rate varies from 100% to 43% with chilled air temperature in the range of 3.3–$14^{\circ }$C and chilling load variation of 100% to 5%. The chilled water flow rate varies from 100% to 32% with supply glycol-water temperature in the range of $-$2.2–$6.1^{\circ }$C. The MWSM uses 11 empirical parameters evaluated from the coil performance data and is able to correlate the data with an adjusted coefficient of determination ($R_{\mathrm{\text{adj}}}^2$) of over 99%. The higher accuracy of the modified model enables the development of a more robust controls strategy required to maintain the inlet air temperature at the set point with varying ambient temperatures and chilling load conditions. The model can also be applied to other chilling and dehumidification applications especially those experiencing wide variations in operating conditions and load or those requiring close control of the chilling and dehumidification process.