Top PDF Thermodynamic Analysis of a Mixed-Mode Solar Dryer

Thermodynamic Analysis of a Mixed-Mode Solar Dryer

Thermodynamic Analysis of a Mixed-Mode Solar Dryer

Thermodynamic analysis of a mixed-mode solar dryer (MSD) has been carried out. The energy and exergy efficiencies in the air heater (AH) were in comparison lower than in the drying chamber (DC) since the heat loss in the AH was more than in the DC. The overall analysis showed that energy and exergy efficiencies in the MSD was slightly higher than those in the AH but slightly lower than those in the DC due to the cumulative effect of energy losses and exergy destruction in the AH and the length of time that was given to the CD utilize the stored energy in the solid to expel moisture. The solid waste was tested and fit for animal consumption. Thus the MSD can be used to dry restaurant wastes for animal consumption.
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SIMULATION OF THE AIRFLOW INSIDE A HYBRID DRYER

SIMULATION OF THE AIRFLOW INSIDE A HYBRID DRYER

Drying is an essential process used all over the world for the preservation of farm produce. It helps in reducing the water activity of the produce to a level below which deterioration doesn’t occur for a definite duration [1]. The drying process helps to achieve better product quality, longer safe storage period and reduction in post-harvest losses. The reduction in post-harvest losses ensures more food availability for growing world population [2]. Various drying methods are employed to dry different food produce. Natural sun drying is probably the oldest method to food preservation. However, it has several drawbacks, such as difficulty to control the rate of drying, insect infestation and microbial contamination. Replacing natural sun drying by artificial drying or by solar drying can significantly reduce these drawbacks and the losses caused by them [3]. Nevertheless, the drying air characteristics in solar dryers depend on ambient conditions, what can reduce the final product’s quality [4]. Artificial drying requires higher operational costs, what can be unfeasible to some applications [5]. In this context, hybrid solar dryers arise as an interesting solution [6]. The characteristics of the drying air can be controllable, improving the quality of dried products and the drying costs can be reduced, comparing with artificial drying. Many solar food dryers have been developed over the past few years, yielding varying degrees of technical performance. Fudholi et. al. [7] divide the solar dryer into four types: direct solar dryers, indirect solar dryers, mixed-mode dryers and hybrid solar dryers. The authors present a review of these types of solar dryers with aspect to the product being dried, technical and economical aspects. The technical directions in the development of solar- assisted drying systems for agricultural produce are compact collector design, high efficiency, integrated storage, and long-life drying system..
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Analysis of ginger drying inside a natural convection indirect solar dryer: An experimental study

Analysis of ginger drying inside a natural convection indirect solar dryer: An experimental study

65 ˚C without and with reflector respectively. The average collector efficiency was reported to increase by 8.04% with reflector. The drying time was observed to reduce by 66.7% against open sun drying [14]. Drying kinetics of ginger rhizomes under blanched and non-blanched conditions was presented using hybrid solar dryer and the drying rate dependency on product shape, size, and drying air temperature was observed. Drying air temperature of 70˚C was reported best for better quality drying of ginger rhizome. Page model was reported best to describe the drying characteristics of ginger rhizome [15]. Thin layer solar drying of ginger was carried out for different mass flow rates of 0.06 and 0.12 kg/s with an average temperature of 54 and 44 ˚C respectively, for which Page model was reported to be most appropriate to describe the drying behaviour of ginger [7]. A solar drier was designed with evacuated tube collectors for ginger drying at different air mass flow rates varying from 4 to 5 m/s and reduced the moisture content of the product from 85.62 to 0.92%. The drier efficiency was reported to vary from 31 to 40.4 % for different air mass flow rates. Overall, the dryer was suggested to be better than other dryers in terms of quality and drying rate [3]. Drying characteristics of ginger using a mixed mode solar cabinet dryer were investigated by reducing its moisture from 621.50 to 12.19%. Solar cabinet dryer was observed to be better for ginger drying in the aspects of quality, drying time, and power requirement as compared to open sun drying. Page model was reported to be most suitable to describe the drying characteristics of ginger [16].
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Experimental Analysis on Forced Draft Solar Dryer with Phase Change Material

Experimental Analysis on Forced Draft Solar Dryer with Phase Change Material

resistance to the flow of heat increases during the heat extraction process. Fig. 5.3 shows the temperature profile on the day. The experiment was performed to determine the maximum temperature of PCM when it was filled in a black selective coated container and placed in the absorber plate of the dryer. The PCM container was also exposed to solar radiation and there was no forced movement of air over the PCM container. The maximum temperature of PCM recorded in the set up was 9l.8°C, which was 15.2°C higher than melting point. The maximum temperatures of the PCM container and outlet of the heat exchanger pipe were, l03.7°C and 95.l°C, respectively. But the absorber plate temperature was 6l.2°C, which was very less compared to the earlier study. The appreciable reduction in the absorber plate temperature was due to the high heat transfer from the plate to the PCM through the container. The recorded maximum temperature of the PCM was an indication of the occurring of phase change, as the measured melting point of acetamide is 76.6°C. The experiment was continued till 7.00 p.m in the night and the temperatures of PCM, container and heat exchanger pipe were, 58.6°C, 55.8°C, and 59.4°C, respectively. The reduction of temperatures was in a very slow mode. While the absorber plate temperature reduced to 39.2°C. Ambient temperature varied from 30.3°C to 33.9°C during 9.30 a.m to 7.00 p.m.
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Explicit and implicit approach of sensitivity analysis in numerical modelling of solidification

Explicit and implicit approach of sensitivity analysis in numerical modelling of solidification

Keywords: Application of Information Technology to the Foundry Industry: Solidification Process: Numerical Tcchniqucs: Sensitivity Analysis; Borzndary Elcmcnt Mcthod.. Introd[r]

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Harnessing ICT to support the mixed-mode delivery framework

Harnessing ICT to support the mixed-mode delivery framework

In short, the use of ICT tools must be purposeful and must support teaching and learning and not merely be preoccupied with technical tasks of searching for information using the Internet and presenting using powerpoint. As an illustration, using WebQuest (DODGE, 2002), my pre-service teachers are assigned tasks, and in these well constructed tasks, they leverage on technological tools like discussion forums and wikis to create and write case studies after watching a videoclip and gathering data from other sources. In doing so, their classmates could critique them and they in turn, could refine their work after having considered all the different perspectives put forth. This is what we mean when we say harnessing ICT for effective teaching and learning in a Mixed-Mode Delivery (MMD) framework.
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An Analysis of Student Evaluations of Native and Non Native Korean Foreign Language Teachers

An Analysis of Student Evaluations of Native and Non Native Korean Foreign Language Teachers

The most common type of complaint from students was un- questionably related to excessive lecturing on the part of the native TA (about 70% of negative comments related to excessive lecturing, not enough time to talk.) Students often felt shorthanded when not given opportunities to discuss topics in class. (Although this contra- dicts the statements above related to difficult discussion topics, we should assume that students who requested more discussion in class are expecting discussion at an appropriate language level.) One stu- dent said of a native male TA, “I think if there were more opportuni- ties to speak instead of hearing him speak for most of the class, it would have been more beneficial.” Another complained about a na- tive female TA, “She was very enthusiastic about teaching, but activi- ties that actually involved speaking were sparse.” More than anything else, students mentioned discussion in the classroom, and the majori- ty of these complaints and requests were aimed towards native female TAs: “I did not like how little we got to speak as a class. My under- standing increased but I feel my speaking skills went down”; “More class participation would have been good”; “I wish we would have had more opportunities to have class debates and class discussions”; “mostly a lecture [with] little interaction”; “I think the only thing that could be improved is if she would have us speak more in class.” Fi- nally, one student wrote an extensive comment for a female TA that depicted her as an outstanding TA, but then ended with the sugges- tion that “more emphasis on free class discussion might help.”
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Simulação do ambiente interno de instalação de beneficiamento e secador solar de café

Simulação do ambiente interno de instalação de beneficiamento e secador solar de café

Drying is considered a critical process step (Borém et al., 2008), in which water activity and metabolic processes are reduced. The coffee is dried in order to maintain its quality and store it for extended periods of time (López, 2005; 2006; Ciro et al., 2011). The main problems in the cup (taste) arise from poor drying and storage (Vilela et al., 2000; Corrêa et al., 2003). Some of these problems bring biological and chemical risks with the product and can lead to a product unfit for human consumption (Puerta, 2008; Oliveros et al., 2013).

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Thermodynamics of the complexation between salicylaldehyde thiosemicarbazone with Cu2+ ion in methanol +1,4-dioxane binary solutions

Thermodynamics of the complexation between salicylaldehyde thiosemicarbazone with Cu2+ ion in methanol +1,4-dioxane binary solutions

MeOH has a higher Gutmann donor number (DN = 19) that that of DO (DN = = 14.8). 41 However, a comparison of the stability constants given in Table I and III revealed that Cu(II) ion was weakly solvated and easily complexed by the ligand in the solvent mixtures with higher contents of MeOH and the stability constants decreased with increasing concentration of DO in the binary solvents. This fact is in accordance with the reverse order of their solvating ability as rep- resented by their Gutmann donor numbers. It is known that the solvating ability of the solvent plays an important role in different complexation reactions. More- over, the stability and selectivity of the formed complexes are affected by a num- ber of molecular factors, such the number and character of the donor atoms in the Schiff base, the polarizibility and charge density of the metal ion, the nature of substituents and the character of the co-anion with the cationic species. 42,43 In the Cu(II)–STSC complex, the ligand binds a Cu(II) ion through its three binding sites (O, N and S) and the fourth coordination site is most probably occupied by the solvent molecules, i.e., MeOH or DO. 16 However, as per the polarity and
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Financial Performance Analysis Of Financial Service Cooperative

Financial Performance Analysis Of Financial Service Cooperative

insufficient operating profit to pay interest, the owner must cover the shortfall. KJK main source of income is the income received from the services of loan. The loan is the provision of funds or claims by other parties who require the borrower to repay their loan with "reward" payment after a certain period of time (Decree of Minister of Cooperative and SME No. 20 / Per / M.KUKM / XI / 2008 Chapter, Article 1). To increase revenue, cooperative should increase granting loans. Manurutng (2012) says that the cooperative business entity who wants to grow must increase granting loans. In addition to providing income, the loan is also a major cause of problems in KJK. So it is not too much to say that the KIN of cooperative is strongly influenced by the success of the manager in managing the loan.KJK which is successfully manage the loan will grow, while KJK which is always undermined non-performing loan will fail. KJK loan management failures trigger problems in financial difficulties which in turn will give impact on the failure to achieve good KIN. Performance is an indicator of the achievement of the organizational tasks. Anthony (1997: 54) defines performance measurement as "the activity of measuring the peformance of an activity or the entire value chain". Bruce (2004: 9) suggests that, "firm financial performance as the total return to shareholders (percentage change in stock price during the year of s donation plus dividends per share as a percentage of the beginning stock price)." KIN is the total of shareholder returns (percentage change in the share price during the year plus dividend per share as a percentage of the initial share price). KIN is the company achievement showed by its financial statements as a representation of the company state during a certain period (Ganguli and Agrawal, 2009). Therefore, the company's financial performance is important for the owner. Arifin (2003) suggests that KIN cooperatives should be assessed on the success of the organization in carrying out two tasks,1) improving the economics of members through the services provided, 2) developing cooperative enterprise through the participation of members. Although cooperative is not profit oriented, but to survive, cooperative needs a strong financial performance because the ability to obtain margin may cover operating costs and gain optimal profit (Dasuki, 2013). To improve KIN of KJK PEMK, the city government allocates a revolving fund, as stipulated in the Regulation of the Governor (Governor Regulation No. 24 year 2008 and Governor Regulation No. 36 year 2012).
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A scalable algorithm to explore the Gibbs energy landscape of genome-scale metabolic networks.

A scalable algorithm to explore the Gibbs energy landscape of genome-scale metabolic networks.

Many important steps have been taken recently to tackle it. At one level, thermodynamic feasibility can be translated into topologic constraints (‘absence of loops’) for the flux configuration emerging from mass-balance constraints [39]. This suggests than an improvement in reversibility assignments (e.g. along the lines of [23]) can be a key to ensure energy balance a priori in metabolic network reconstructions, with the caveat that the possibility that a reaction reverses can depend on the boundary conditions (e.g. the external supply of a certain metabolite) or on intracellular perturbations (e.g. a knockout causing the accumulation of an intermediate metabolite) [12]. Another possibility consists in building mixed integer-linear constraint-based models that include thermodynamic requirements in the form of consensus rules (using information on standard Gibbs free energies) [13] or as additional constraints on metabolite levels (using information on measured intracellular concentrations) [12]. Here we have followed a different though related route that in our view complements the approaches just described. The starting point is the fact that, given a flux configuration, thermodynamic constraints can be written as simple stoichiometric inequalities for the chemical potentials. Feasibility implies the existence of a vector of chemical potentials Table 1. Thermodynamically infeasible cycles for the E. coli
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Modeling and Analysis of Queuing Systems in Banks A case study of Ghana Commercial Bank Ltd. Kumasi Main Branch

Modeling and Analysis of Queuing Systems in Banks A case study of Ghana Commercial Bank Ltd. Kumasi Main Branch

The model adopted in this paper is multiple channel queuing system, in which two or more servers or channels are available to handle arriving customers. Let still assume that customers waiting service form one single line and then proceed to the first available server. For this queuing system, it is assumed that the arrivals follow a Poisson probability distribution with rate . Each of these channels has an independent and identical exponential time distribution with mean 1 .

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Kinetics and Thermodynamics of Cd(II) Ions Sorption on Mixed Sorbents Prepared from Olive Stone and Date Pit from Aqueous Solution

Kinetics and Thermodynamics of Cd(II) Ions Sorption on Mixed Sorbents Prepared from Olive Stone and Date Pit from Aqueous Solution

The removal of toxic metals from wastewater is matter of great interest in the field of water pollution, which is a serious cause of environmental degradation. Besides the classical waste-water treatments, biosorption of heavy metals is an alternative technique, primarily because it utilizes inactive dead biological materials as sorbents which are generally available at low cost, non hazardous and abound in nature (Veglio and Beolchini, 1997; Volesky, 2001). In the last years, certain raw waste products from industrial or agricultural operations i.e., pine bark (Al-Asheh and Duvnjak, 1998), grape stalks (Villaescusa et al., 2004), crop milling waste (Saeed et al., 2005; Krim et al., 2006; Kula et al., 2008) have been tested for decontamination of metal-containing effluents.
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Analytical model of asymmetrical Mixed-Mode Bending test of adhesively bonded GFRP joint

Analytical model of asymmetrical Mixed-Mode Bending test of adhesively bonded GFRP joint

he pultruded GFRP laminates, supplied by Fiberline A/S, Denmark, consisted of E-glass fibers and isophthalic polyester resin. The laminates with 6 mm in thickness consisted of a thin polyester veil in the outer surfaces, two combined mat layers on each side and a roving layer in the middle. Each mat layer comprised of 0/90 woven fabric stitched to a chopped strand material. The fiber architecture of the laminate is schematically shown in Fig. 1. Based on burn-off test, according to ASTM D3171-11 [15] and fiber density of 2560 kg/m3, the fiber content was 43.3 vol. %. A two-component epoxy adhesive system Sikadur 330, Sika AG, Switzerland, was used for the bonding of the GFRP Figure 1: Scheme and micrograph of the laminate
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Tracking Error Analysis of a Rotation-Elevation Mode Heliostat

Tracking Error Analysis of a Rotation-Elevation Mode Heliostat

The two prototypes of NIFH [1] built in UTM are structurally close-loop. The feedback signal from the optical encoder will eliminate the tracking error due to the mechanical lashes, wind effect and other disturbances to the heliostat frame. The pointing error existed in the tracking is basically due to the error of the parameters (i.e. the orientation angles of the rotation axis respect to the target, the latitude, etc.) and the imperfection of mechanical design. The imperfections of the mechanical design in the heliostat structure are the translation offset of reflector from the elevation axis, the mechanical alignment between the elevation axis and the rotation axis etc. In order to determine the accurate parameter, systematic analysis of the image movement has been performed using computer simulation.
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Analysis of Fast- ICA Algorithm for Separation of  Mixed Images

Analysis of Fast- ICA Algorithm for Separation of Mixed Images

The Fast-ICA algorithm belongs to the family of fix-point algorithms for ICA, which was based on the iteration to search for the maximum of the non-Gaussianity of variables. In this paper, we shall first review the fundamental theory and basic model of ICA in section II, and then shall elaborate upon the math principle of the fast fixed-point algorithm for ICA. We shall apply the algorithm in blind separation of randomly mixed images in section III, and finally some conclusions shall be drawn in section IV.

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Design Fabrication And Partial-Analysis Of A 2-Wheeler Prototype That Runs On Compressed Air

Design Fabrication And Partial-Analysis Of A 2-Wheeler Prototype That Runs On Compressed Air

The solenoid valve actuation and the pulse control is achieved using an optical crank position sensor circuit. The circuit mainly consists of vital components: optical emitter-receiver (OPB732), Astable multivibrator (LM555) [4] , TIP 122 Darlington pair [5] , 200kΩ Trimpot. The working is as explained below:

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Rev. Nutr.  vol.27 número1

Rev. Nutr. vol.27 número1

The sampling strategy used by the present study is complex because selection of the grades and finally, the classes that encompassed this population group required taking into account both the age bracket of adolescents, which, according to the World Health Organization (WHO), ranges from 10 to 19 years, and the schools listed in the state network. Students aged 10, 18, and 19 were excluded from this population group because very few students in the study grades were that old. Therefore, the sampling calculation used Simple Random Sampling Without Replacement (SRSWOR); schoolchildren selection relied on a two-stage cluster sampling: the first stage consisted of selecting the schools, and the second stage of selecting the classes. Twenty-one schools were selected from the 207 state schools, and three classes were selected from each school and in each, given that each class had approximately 30 students. All students who agreed to participate in the study and obtained their guardians’ consent were interviewed. The study was approved by the Research Ethics Committee of Universidade Federal da Bahia (UFBA) Institute of Collective Health under Protocol number 002/08 CEP/ISC. The students’ guardians who agreed with their children’s participation in the study signed a free and informed consent form or provided their fingerprints if they were illiterate.
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THE SIGNIFICANCE OF TRAVELLER’S ROUTE KNOWLEDGE FOR CHOICE OF COMMUTING MODE OF TRANSPORT

THE SIGNIFICANCE OF TRAVELLER’S ROUTE KNOWLEDGE FOR CHOICE OF COMMUTING MODE OF TRANSPORT

17 subsequently mentally represent our immediately surrounding geographic space. The research was conducted by testing how rats behave in artificial mazes, how do various conditions influence their navigation performance and how do they adapt to changing situations. Tolman proposes that a mental map consists of paths and routes and includes “environmental relationships” between them. “Strip-like” or “narrow” and “comprehensive” varieties of mental maps are identified. Map of a narrow type can be thought of as a one-dimensional route between origin and destination. Its 1D character doesn’t mean that the route is a straight line, but rather that there are no branches or alternative routes included in the map – one can only move forward or backward along the route. In contrast, comprehensive maps include more full information about the environment such as a number of alternative, equivalent routes between the origin and the destination. In practice, most mental maps available to agents are somewhere between the two types: one typically has a better knowledge of the city they live in than just one route between his home and office, but also hardly ever does one have a complete knowledge of all the streets, buildings and other features. A mental map may be more comprehensive in areas which one visits frequently, such as the surroundings of one’s home, and more narrow in places only visited seldom. Tolman argues that results of his experiment point to conclusions that are just as relevant for humans as for his lab animals.
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Modelling the drying kinetics of green peas in a solar dryer and under open sun

Modelling the drying kinetics of green peas in a solar dryer and under open sun

developed for a particular product. Indirect type of solar crop dryers is well recognized and it overcomes the inherent problems of open sun dryers and cabinet dryers [4]. Solar energy has found vast application in solar thermal systems [5-10], solar drying is particularly one of them that used mostly in developing countries [11]. The proper design of solar dryers not only fulfills particular drying needs but also augments energy efficiency. Solar dryers of various types find applicability all over India because of its high insolation and abundant sunshine duration. Drying of agricultural product is one of the important post harvest processes and it has sufficient ability to diminish the post harvest losses to a large extent. Drying can also prevent spoilage of the product in storage significantly. A good drying technique can enhance the quality of the product drastically [12].
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