摘要:

AbstractThe combined generation of electricity by wind and solar energy is a very attractive solution for isolated regions with high levels of yearly wind energy and insolation. A computer model is developed for the simulation of the electricity system of a Mediterranean island, including a wind power plant, a photovoltaic power plant and a storage system. In order to obtain an overall view of the system performance and economic aspects, the model also incorporates a number of diesel generators. Daily simulations for the Greek island Kythnos show that such a combined system of moderate size can provide a large fraction of the electrical energy requirements. Various parameters calculated in the simulation can be used to improve the configuration of the system and to estimate the cost of the electrical energy unit.

ISSN:0363-907X    

DOI:10.1002/er.4440100102

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractA CANDU‐CANDU(Th/Pu)‐LMFBR(PuO2) nuclear power system is considered, on a 65 year time horizon. The system is characterized by a number of independent variables and integral parameters that depend on them. In performing the optimization of the system we outline first of all the following components of the independent variable vector:(1) DT1—the delay time in reprocessing Pu from CANDUs, (2) DT2—the delay time in reprocessing Pu partially consumed in the CANDU (Th/Pu)s, (3)b3—the fuel burn‐up in CANDU (Th/Pu)s, (4)q—the control parameter of the total power growth. The components of the independent variable vector, also called decision variables, are subjected to some direct restrictions. In this paper it is admitted that, from the multitude of integral parameters of the system, the annual electric energy has the greatest importance in the case of a non‐econometric approach. This is the objective function of the system optimization problem and depends on the independent variable vector or decision vector. In addition, from the fuel resource point of view, the Unat and Pu cumulative consumptions have a special importance. These are called restriction functions because one looks for the decision vector subject to some direct restrictions (on components) so that, some restrictions on the consumption functions being satisfied, a maximum of the annual electric energy produced in the system at the end of the considered interval is obtained. In this way, the problem has a clear structure of an optimization model of non‐linear programming type and it can be treated in specific way for a given field of the above restriction function values. As a result, a set of optimal solutions for development of a CANDU‐CANDU(Th/Pu)‐LMFBR(PuO2) system, of interest from a nuclear energy policy point

ISSN:0363-907X    

DOI:10.1002/er.4440100103

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractIn the present investigation, the process of diffusion of salt in a vertical column of liquid, subjected to temperature variations of the typesT(x) = constant, linear ( =a + bx) and parabolic ( =a + bx ‐ cx2); with a constant concentration difference between the top and the bottom (0 and 25 per cent, respectively) is studied. It is seen that a linear temperature gradient,T(x) =a + bx, leads to a near convex parabolic salt concentration profile with maximum deviations increasing from 13.5 per cent (at 40°C) to 14.8 per cent (at 70°C) and eventually to 15.7 per cent (at 90°C) with respect to the linear concentration value of 12.5 per cent (by weight) at the midpoint. Conversely, the parabolic temperature profile as well as the modified profile due to the Soret effect leads to near cubic salt profiles which differ only by 2–3 per cent in the upper half of the pond. However, they show a point of inflexion at larger depths near the bottom around which the convex profiles change over and become concave. Subsequently, these studies have been extended to compute the salinity profiles of thermal configurations of the operational sola

ISSN:0363-907X    

DOI:10.1002/er.4440100104

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractResults of optical and thermal performance evaluation tests conducted on a prototype linear Fresnel reflector system fabricated using locally available material are presented in this paper.

ISSN:0363-907X    

DOI:10.1002/er.4440100105

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractCorrelating performance parameters for fuels, such as ring carbon, aromatic percentage, carbon number, C/H mass ratio and hydrogen percentage, have proved to have relative correlating deficiencies. Although hydrogen percentage is the most successful, so far, it is postulated that the Gibbs function is more powerful owing to its direct relation with the chemical potential, which causes reactions to take place.This parameter gave favourable trends when checked against different previous works on gas turbine combustors especially with flame radiation, smoke and liner temperature. However, improvement over hydrogen content is marginal.

ISSN:0363-907X    

DOI:10.1002/er.4440100106

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractIn this paper, the thermodynamic properties of lithium nitrate‐ammonia mixtures are presented. The vapour pressure‐temperature correlations are developed by fitting the experimentalP‐T‐xdata. The enthalpy of solution, the latent heat of vaporization, the integral heat of solution and the differential heat of solution are presented in appropriate tabular and graphica

ISSN:0363-907X    

DOI:10.1002/er.4440100107

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractThe application of Glauber salt as a latent heat storage material is a difficult technical problem owing to the separation of the coexisting phases (stratification) during melting. In order to avoid stratification and to improve the heat transfer in the course of the charge and discharge, a new storage type called ‘GLS’ was developed, in which the heat is transferred in a closed container to the latent heat storage material by means of the vapour of a heat transfer liquid. Surface‐active materials which were added to the storage materials produce optimum conditions for the heat transfer and material transport during the heat transfer processes.Under the conditions of the GLS storage unit on application of Glauber salt, constant storable amounts of energy were found which are in good agreement with the theoretical values. The heat storage can be performed with high energy densities in narrow temperature differences and with high power of the transferred

ISSN:0363-907X    

DOI:10.1002/er.4440100108

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractThe objective of this paper is to develop a computer‐aided optimal planning method for designing a marine heat and power generation plant which is composed of combining Diesel and turbogenerators, an exhaust gas economizer, auxiliary boilers and so forth. As there exist many alternative combinations concerning generators and boilers in constructing the abovementioned plant, it is important to determine the plant construction properly by selecting total numbers and scales of respective generators and boilers so as to optimize the long‐term economy of the plant.In this planning method, several design conditions are first set which are necessary for the planning of the objective plant, i.e. several patterns of ship's operational condition are set first, and both energy demands and steam output from an exhaust gas economizer are estimated for each pattern. Next, setting an alternative plant composed of combining generators and boilers adequately, the optimal operational policy for each pattern is determined by minimizing the fuel cost under several physical constraints based on linear and quadratic programming methods. Considering the results obtained above hierarchically, annual capital and operational costs of each plant are calculated, and the best plant construction is lastly determined by comparing the economy of all alternative plants.A numerical study has been carried out on a plant of a high speed container ship actually planned, and it is ascertained that to find the best construction of the plant the optimal planning method proposed here is advantageous compared with the conventional trial and error met

ISSN:0363-907X    

DOI:10.1002/er.4440100109

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractInternational Energy conservation developments and programmes for institutional buildings, industrial processes, agricultural operations, residential buildings, land use planning and transport services are summarized. The topics were presented by experts to an international audience at ENERGEX ′84 held in Regina, Saskatchewan, Canada during May 198

ISSN:0363-907X    

DOI:10.1002/er.4440100110

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractThis paper reports the design, development and testing of an improved multipurpose solar energy device. The novel feature of the device is that it can be used as a solar water heater and solar still simultaneously and, when required, as a solar cabinet dryer by incorporating minor changes.

ISSN:0363-907X    

DOI:10.1002/er.4440100111

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY