Performance Assessment of a Solid Desiccant Air Dehumidifier (original) (raw)
Related papers
Thermal Science, 2017
This paper presents real time performance analysis of a silica gel based desiccant wheel dehumidifier. Thermodynamic model is also validated through comparison under a wide range of operating conditions for subtropical climate conditions. Initially, a mathematical model is developed by using various set of equations for desiccant wheel dehumidifier in engineering equation solver. Afterwards, a parametric analysis of the system is performed including various design and climate parameters such as: inlet air humidity ratio, inlet air temperature, regeneration inlet humidity ratio, regeneration temperature, and rotation speed of the wheel. Then, an experimental setup of the system is established in Taxila Pakistan for the real-time performance assessment. The results revealed that the optimal rotation speed of desiccant wheel ranged from 15-17 rph. The maximum model based and experimental effectiveness is 0.45 and 0.43, respectively at regeneration temperature of 80 °C. The maximum and minimum root mean square error values for effectiveness are 3.2% and 2.1%, respectively. Thus, the comparison between experimental and model results showed a good agreement.
Experimental analysis on the dehumidification and thermal performance of a desiccant wheel
2012
The advantages of desiccant-based air conditioning systems, compared to conventional ones based on the dehumidification by cooling, have been highlighted in many research papers. The energy saving and the reduction of the environmental impact are higher when the desiccant material is regenerated by using ''free'' thermal energy (for example, waste heat from cogenerators or solar energy). Further investigation on the performance of the desiccant wheel is useful: therefore, in this paper, an experimental analysis on this component is presented, with particular attention to the variation of the performance as a function of the process and regeneration air flow rates. The desiccant material is regenerated by means of lowtemperature thermal energy (about 65°C) from a microcogenerator. Both the experimental results obtained by the authors and the data provided by the manufacturer have been used to calculate some performance parameters, and a satisfactory agreement has been obtained.
Effect of Regenaration Air Temperature on Desiccant Wheel Performance
International Journal of Technology, 2016
Desiccant wheels are used as an air dehumidifier in airconditioning and industrial applications. Desiccant wheel performance determines the size and cost of the whole system. A good desiccant wheel is one that saves energy usage. This article presents an experimental investigation on the effects of varying the regeneration air temperature, viz., 50, 60 and 70 o C, on desiccant wheel performance. Three performance criteria were considered, namely condition of process outlet air, dehumidifier efficiencies and dehumidification rate. Two kinds of efficiency of the desiccant wheel dehumidifier were examined, namely thermal and dehumidification efficiency. Results of the experiments show that increasing the regeneration air temperature increases the dry bulb temperature of the process outlet air. However the moisture content of the process outlet air is reduced. The dehumidification efficiency of the desiccant wheel decreases with increasing regeneration air temperature, i.e., 46.7, 45.8 and 45.3 % for 50, 60 and 70 o C, respectively. In contrast, the dehumidification rate increases with an increase in the regeneration air temperature, namely 32.6, 37.1 and 40.2 g/h for 50, 60 and 70 o C, respectively.
Effect of regeneration air temperature on the performances of a desiccant wheel
2015
Desiccant wheels have been used as an air dehumidifier in air-conditioning and industrial applications. The performances of the desiccant wheel determine size and cost of the whole system. A good desiccant wheel is one that would save energy usage. This article presents an experimental investigation on the effects of varying the regeneration air temperature, viz., 50, 60 and 70°C, on performances of a desiccant wheel. Three performance criteria were considered, namely condition of process outlet air, dehumidifier efficiencies and dehumidification rate. Two kinds of efficiency of the desiccant wheel dehumidifier were examined, namely thermal and dehumidification efficiency. Results of the experiments show that increasing the regeneration air temperature increases the dry bulb temperature of the process outlet air. However the moisture content of the process outlet air is reduced. The dehumidification efficiency of the desiccant wheel decreases with increasing regeneration air tempera...
Performance analysis of a solid desiccant air dehumidifier
2015
A desiccant air dehumidification system is widely used in many applications such as refrigeration, crops drying, food industries, pharmaceutical and air-conditioning. The thermal effectiveness is often used to represent the performance of the system. Its value depends on the psychrometric properties of the incoming air and several other parameters. This article presents an experimental study to determine the thermal performance of a compact solid desiccant air dehumidifier. The effects of percent opening combination of the control valve for the process and regeneration air ducting on the thermal performances of the dehumidifier was investigated. An experimental rig was fabricated for these purposes. It consists of a solid desiccant air dehumidifier, process and regeneration air ducts, instrumentation and data acquisition system. Experimental data were acquired under a steady-state operating condition, for three cases of control valve opening combinations. It was found that the therm...
CFD Analysis of Solid Desiccant Dehumidifier Wheel
International Journal of Analytical, Experimental and Finite Element Analysis (IJAEFEA), 2021
Desiccant cooling and dehumidification systems control both the air humidity as well as the operating cost by reducing the energy requirements of the supply air systems. This study used flow simulation CFD high resolution to better understand the vapor flow through complex porous media. The CFD simulation of the adsorption cooling system showed that the design could have beneficial effects on the performance of the system. The emphasis is on optimizing the process to remove the moisture, and the optimal process inflow velocity for the particular desiccant wheel model is determined to be between 1.5 and 2.5 m/s.
Experimental Investigation of the performance of a Desiccant Wheel
University of Khartoum Engineering Journal, 2012
Desiccant cooling systems have the potential to make a major contribution to the reduction of both CFC’s and electricity peak load. An experimental investigation on the sensible effectiveness of a desiccant wheel is conducted. Measurements were made for a range of rotational speeds (0-5 rpm), regeneration temperature (50 to 60oC). A computer based calculation procedure using Excel worksheet was built, and applied to estimate the effect of the desiccant wheel speed on the moisture removal and the sensible effectiveness. The calculations were based on the experimental data that obtained by the digital multimeter during the experiment. The results succeeded in determining the optimum rotational speed for the desiccant wheel, the sensible effectiveness, the moisture removal efficiency and the dehumidification coefficient of performance. It was found that the lower speeds have better results than the higher ones.
An Experimental Study of Desiccant Wheel-Air Humidifier Integration in Hot and Dry Climates
The International Conference on Applied Mechanics and Mechanical Engineering, 2014
Desiccant dehumidification has emerged as an alternative or as a supplement to conventional vapor compression systems for cooling and conditioning air in commercial and industrial buildings to remove the latent heat load. The advantages of desiccant-based air conditioning systems, compared to conventional ones based on the dehumidification by cooling, have been highlighted in many research papers. The energy saving and the reduction of the environmental impact are higher when the desiccant material is regenerated by using ''free'' thermal energy. We study performance of air humidifier cooler systems with a rotary desiccant wheel, as the heat and moisture transfer medium in hot and dry climates as an alternative to vapor compression cooling. The wheel is symmetrically balanced and is operated with counter-flow pattern. This investigation examines the effect of operating conditions and different design parameters of desiccant wheel with air humidifier cooler such as: the regeneration temperature, regeneration air mass flow rate, desiccant wheel rotational speed, silica gel quantity (porosity), concentration of calcium chloride solution (mass%), and the concentration of sodium chloride solution (mass%). Air humidifier cooler and desiccant wheel are conducted on a lab-scale unit. Test rig consists of a main unit and accessories were carried out in the laboratories of Faculty of Energy Engineering, Aswan University.
Simulation Study of Desiccant Dehumidifier: A Review
International Journal of Advanced Research in Science, Communication and Technology
Traditional cooling systems based on vapor compression are ineffective in humid climates due to their inability to remove moisture below the dew point of the conditioned air, which involves additional effort in the form of an electrical power supply to run vapor compressors. A solid desiccant cooling system reduces powerusage while simultaneously providing fresh and clean air. It is important toexamine and analyze the performance of desiccant dehumidifiers using the Different pattern in the desiccant wheel that will help to develop a more efficient cooling system. Like ahoneycomb, triangular, sinusoidal.To study different type of material used in desiccant wheeel to adsorp the air moisture. Study different simulation technique used in desiccant.
2019
Air-conditioning systems combined with rotary dehumidification were widely used in industrial buildings with low humidity requirements. In this paper, a rotary desiccant wheelbased hybrid air conditioning system with natural cold source was presented, which was used in civil buildings. In this system, sensible load was undertaken by the natural cool source, and latent load was undertaken by rotary dehumidification wheel. The performances of rotary desiccant wheel-based hybrid air conditioning system with natural cold source were studied in two typical outdoor meteorological conditions. The results showed that the system under both high temperature high humidity and high temperature low humidity conditions can satisfy the indoor environment demand for civil buildings, while the energy consumption on high temperature high humidity condition is less. While waste heat or solar energy is adopted as regeneration heat source, the energy consumption of rotary desiccant wheel-based hybrid ai...