Pdf design and simulation of a solar assisted desiccant. We used this model to simulate the system during the cooling period in five. Results indicated that the pressure drop and the adsorption rate of desic. Iea shc task 38 solar air conditioning and refrigeration subtask c2a, november 9, 2009 page 7 chapter i. Description of simulation software, applicable for solar cooling in this chapter a brief description of some simulation tools applicable in solar cooling is given.
This study demonstrates that economic savings up to 54% percent can be achieved in the running costs of desiccant cooling systems when compared to traditional compressor. Jul 05, 2018 this results in water vapour being transferred from the oa stream to the rg stream. Dynamic simulation of a solar desiccant cooling system. These can also be operated using nonconcentrating solar collectors. Introduction desiccant cooling technology provides a tool for controlling humidity moisture levels for conditioned air spaces.
In this research, solar desiccant cooling cycles in ventilation and hybrid mode are simulated. Simulation and energy efficiency analysis of desiccant wheel. Series regeneration in a desiccant system places the regeneration side of the wheel upstream of the cooling coil and the process side downstream of the coil. Solar thermal energy is hereby used to provide cooling. May 29, 2012 this breakthrough combines desiccant materials, which remove moisture from the air using heat, and advanced evaporative technologies to develop a cooling unit that uses 90 percent less electricity and up to 80 percent less total energy than traditional air conditioning. During the cooling season, the coldest part of the system is that which is directly downstream of the cooling coil. An overview of opencycle desiccant cooling systems and materials. There are di erent ways of capturing solar energy in order to use it as a source of regeneration energy required in solid desiccant cooling systems, and the most fashionable of these capturing methods is the use of solar collectors, which can be employed in. The thermally driven cooling cycle is a combination of evaporative cooling with air dehumidification by a desiccant, i. Desiccant based evaporative cooling system operating in ventilation cycle pennington cycle. Simulation of dynamical performance of solar desiccant cooling. Simulation analysis of the four configurations of solar. In order to achieve this objective a userfriendly software was created, called the dcss desiccant cooling simulation software that simulates the operation of the system during a. Simulation of dynamical performance of solar desiccant.
The ansys and trasys software were used to predict the results of dehumidifiers and the desiccant. Abstractrecently, desiccant cooling systems are well thought of as a. In present paper solar assisted desiccant cooling system simulated using trnsys for ventilation and recirculation mode of a lecture hall of 30 kw cooling capacity. The aim of this research was to study and design a solid desiccant dehumidification system suitable for tropical climate to reduce the latent load of airconditioning system and improve the thermal comfort. Desiccant based evaporative cooling system operating in ventilation cycle with double series ew. Development of simulation modules for liquid desiccant.
Received 1 july 2011 received in revised form 21 october 2011. Two models of solar assisted solid desiccant cooling systems are designed by using simulation studio software based on ventilation and. To support and validate simulation data, one basic desiccant cooling system as shown in figure 1 was installed. Desiccant cooling systems process water vapor in the earths atmosphere. Desiccant cooling analysis simulation software, energy, cost. Trnsys simulation for solarassisted liquid desiccant. The trnsys simulation software has a wide interdisciplinary user.
Active heat and cooling program has been pursuing basic research and development in the area of solid desiccant solar. Some commented examples are presented to illustrate how. In this paper, simulations were used to predict the performance of dehumidifiers and the desiccant cooling systems. Two models of solar assisted desiccant cooling system are designed by simulation studio software based on ventilation and recirculation mode. This study performs a deep economic and environmental analysis of the desiccant cooling systems, comparing it with traditional vapor compression based systems. Analyze a desiccant cooling system for two operating modes for different re generation temperatures to identify the. Modelling of a solar desiccant cooling system using a trnsys. Four types of desiccant cooling systems with low and high dehumidifycation capacities were evaluated by using trnsys simulation software. Modeling and simulation of a desiccant assisted solar and. Simulation of potential standalone liquid desiccant cooling. Trnsys simulation for solar assisted liquid desiccant. Solar assisted desiccant evaporative cooling system for o ce.
The present research investigated the dynamic operation of a solar desiccant cooling system coupled with a ground source heat exchanger gshe. For optimization of the cooling system, cycle is divided into two parts, one is liquid desiccant system with compression cooling cycle and organic rankine cycle and the other is solar heating system. Solar assisted desiccant air conditioning system for hot and. To simulate cycles, at first a model for desiccant wheel simulation is presented and a computer code based on experimental correlations is used to solve equations. Comparison simulation between ventilation and recirculation. Solar flat plate collector has been used as it decreases the dependency on nonrenewable resources. Its performance can be evaluated by simulating it with trnsys simulation software which depends on many operational and geometrical parameters of the thermal system. Desiccant cooling analysis simulation software, energy. Pdf simulation of desiccant cooling systems using trnsys. Desiccant evaporative cooling dec is one of those techniques. The designed solar assisted desiccant cooling system is successively simulated by means of trnsys software, in. In this paper, the principles underlying the operation of desiccant cooling systems are recalled and their actual technological applications are discussed. This is because of the fact that the system was modeled in two parts in two different software.
The ansys and trasys software were used to predict the results of dehumidifiers and the desiccant cooling systems, respectively. Simulation software, energy, cost and environmentalanalysis of desiccant cooling system artieda urrutia, juan university of gavle, faculty of engineering and sustainable development, department of building, energy and environmental engineering. Development of simulation modules for liquid desiccant systems in sorpsim master of science in engineering ming qu eckhard groll travis horton ming qu dulcy abraham 04202015 to the best of my knowledge and as understood by the student in the thesisdissertation agreement. Desiccant cooling systems are basically open cycle systems, using water as refrigerant in direct contact with air. More details on the con gurations and simulation process will be explained in the subsections below.
Both matlab and trnsys simulation software is considered individually for modelling. Solar assisted desiccant air conditioning system for hot. Generally, depending on using dehumidification material, there is two kind of desiccant cooling system. A possible solution to reduce the energy consumption for cooling could be by using solar thermal cooling systems. Two models of solar assisted solid desiccant cooling systems are designed by using simulation studio software based on ventilation and recirculation mode.
It also demonstrates that desiccant cooling is more appropriate in dry climate zones with low latent heat generation gains. Both trnsys and matlab can be used on their own to model and simulate a solar assisted desiccant cooling system. As the desiccant removes the moisture from the air, desiccant releases heat and warms the air, i. Desiccant cooling simulation software that simulates the operation of the system during a year and performs automatically all the necessary calculations.
Modelling of a solar desiccant cooling system using a. Desiccant cooling is a technology that, based on a open psychrometric cycle, is able to provide cooling using heat as the main energy carrier. Desiccant cooling systems require electricity to operate pumps and fans and heat energy to preheat the desiccant solution for regeneration. As the desiccant system can operate on low heat, heat energy can be provided through solar thermal systems or any waste heat source from chimneys, power plants, etc. The cooling effect of a dec system is based on the adiabatic cooling principle. These systems all use a liquid or solid material called a desiccant to remove water vapor from the air. Different dehumidifiers such as desiccant column and desiccant wheel were investigated. Figure 2b shows modeling of solar desiccant cooling system in ventilation mode that was designed by trnsys software. Simulations were conducted in hothumid and moderatehumid climates. Tas desiccant wheel simulation comparison edsl tas.
Trnsys simulation for solarassisted liquid desiccant evaporative. Ldcs liquid desiccant cooling systems, capable of achieving dehumidification and cooling with lowgrade heat input, can be effectively used for treating fresh air in hot and humid regions. Trnsys simulation for solarassisted liquid desiccant evaporative cooling. The uses of a trnsysmatlab cosimulator as a strategy for detailed modelling, optimization and control. Optimization of the open absorption desiccant cooling system has been carried out in the present work. A finite difference method is used to simulate the combined heat and mass transfer processes that occur in the liquid desiccant regenerator which uses calcium chloride cacl2 solution as the working desiccant. A cooling coil is often required downstream of the desiccant to cool the air to a practical and usable temperature. Recently, desiccant cooling systems are well thought of as a competent method of controlling the water content in the air. A groundcoupled desiccant assisted air conditioning system is simulated. Desiccant planning, programming and budgeting guide a. Desiccant cooling methods is investigated briefly including desiccant materials, and cooling methods. In order to achieve this objective a userfriendly software was created, called the dcss desiccant cooling simulation software that simulates the operation of the system during a year and performs automatically all the necessary calculations. Desiccant column design in this simulation study, spherical particles of silicagel were used as the working desiccant in the column. The coefficient of performance cop of the desiccant cooling system, regeneration temperature, mass flow rate, fresh air, and relative humidity of the supply air are the important parameters considered by the researchers.
A solid desiccant and vapor compression hybrid airconditioning system for a test room of cooling capacity 1. Since mass transfer occurs between the system and its envi ronment, they are commonly referred to as opencycle systems. Xia school of mechanical engineering, institute of refrigeration and cryogenics, shanghai jiao tong university, shanghai 200030, china received 22 june 2004. It is for this reason that it would be desirable to place the desiccant wheel downstream of the cooling coil, rather than upstream, as in the previous example.
The desiccant bed contained approximately 15 kg of silicagel, with 3 mm average diameter. Solar energy and gshe were used as a heat source for regenerating the desiccant and a pre cooling component, respectively. Then by trnsys software a model for solar hot water system is simulated, and eventually by representing a suitable algorithm, computer program for simulating. Computational fluid dynamics cfd simulations for the effect. Moisture is adsorbed from the process air downstream of the cooling coil and is placed back upstream of the coil. Numerical simulation of a novel trombe wallassisted. The experiment and simulation of solid desiccant dehumidification. The ventilation mode is an open cycle system which has two air flows of regeneration and process.
This paper describes the work to develop of a specific user interface into odesse platform to design and simulate different dec configurations and to compare it with a reference conventional system. These tools are the most commonly used by iea task 38 participants. Review of a desiccant cooling system using a matlabtrnsys. Optimization of desiccant absorption system using a genetic. Desiccants in either solid or liquid forms have a natural affinity for removing. Design and simulation of a solar assisted desiccant based air handling unit. Desiccant and evaporative cooling systems dec in a novel software platform for dynamic simulation of the whole buildinghvac system called odesse. Solid desiccant assisted cooling and dehumidification systems are becoming very popular nowadays for maintaining the required thermal comfort in different residential and industrial cooling applications. This negates the need for a separate regeneration air stream. The physical properties of silicagel are average 3 mm diameter, porosity of 0. Simulation of hybrid desiccant cooling system with. Although the desiccant wheel removes latent heat moisture from the process air stream, sensible heat is added. Proceedings of the 22th national and 11 th international ishmtasme heat and mass transfer conference december 2831, 20, iit kharagpur, india hmtc0273 simulation of desiccant cooling systems. The first desiccant cooling system was recorded by pennington in 1955 2.
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