摘要:

AbstractThe combined effects of Hall current and a constant heat source on the hydromagnetic free convective and mass transfer flow past an infinite vertical porous plate in a rotating porous medium are considered, when the temperature of the plate varies with time about a nonzero constant mean and the temperature of the free stream is constant. The problem is solved analytically and the velocity profiles are shown on graphs. Effects ofm(Hall parameter) and α (heat source parameter) on velocity are discussed extensively

ISSN:0363-907X    

DOI:10.1002/er.4440150202

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

年代:1991

数据来源: WILEY

摘要:

AbstractIn the paper, an attempt is made towards the development of a linear programming micromodel for determining an optimal mix of technologies for domestic cooking in the rural areas of India. A mathematical model involving common sources (including biomass, commercial and solar) and commercially available technologies is formulated along with the detailed technoeconomics of the different energy conversion routes. In order to make the developed model flexible, the cooking sector is divided into two subsectors, namely the low temperature thermal energy requirement and end uses requiring thermal energy at mediumhigh temperatures. The marginal costs of both, the different energy resources, and the possible energy conversion routes are discussed in the context of rural India. The paper forms a part of a larger exercise of formulating a micromodel for the design of a rural energy supply system involving the three major end uses of energy in rural areas of India, i.e. cooking, irrigation and lighting.

ISSN:0363-907X    

DOI:10.1002/er.4440150203

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

年代:1991

数据来源: WILEY

摘要:

AbstractThe paper examines the application of the constant‐injection tracer‐gas technique for the measurement of airflow in smooth and artificially‐roughened ducts. Experiments were carried out for the ratio of rib to duct height (K/H) of 0.1 and for a ratio of rib spacing to rib height (P/K) of 10. A comparison between tracer‐gas measurements and measurements made with a pitot tube showed that the closest agreement was obtained when experiments were performed in the rough duct. Relationships for the friction‐factorfand Reynolds number Re are presented both for smooth and ro

ISSN:0363-907X    

DOI:10.1002/er.4440150204

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

年代:1991

数据来源: WILEY

摘要:

AbstractThe paper examines the total energy input requirements and outputs of subsistence agriculture in the rural areas of Nepal with specific emphasis on animate energy inputs for different crops. It analyses the availability of animate energy and the usage pattern and also looks into various issues of energy demands in subsistence agriculture at micro levels and its impact at macro level. The paper attempts to highlight major policy options that are imperative for raising the living standard of the rurals through increased productivity.

ISSN:0363-907X    

DOI:10.1002/er.4440150205

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

年代:1991

数据来源: WILEY

摘要:

AbstractA simple algorithm to simulate the transient behaviour of a vapour compression heat pump is described. Individual models are developed for various components of the heat pump such as compressor, evaporator, condenser and expansion valve. The components are simulated separately and are combined to form the total system. The compressor is a hermetically sealed, reciprocating piston type with adiabatic compression, the evaporator and condenser are coiled copper tubes, and the expansion valve is assumed to be adiabatic. The transport and thermodynamic properties of the refrigerant used are obtained from empirical equations. The total system is viewed in a simplified manner in order to apply the results of this transient analysis to the behaviour of a chemical process operation, namely, distillation.

ISSN:0363-907X    

DOI:10.1002/er.4440150206

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

年代:1991

数据来源: WILEY

摘要:

AbstractA model to simulate the transient behaviour of a heat pump assisted distillation column is presented. The packed bed distillation column is treated as a distributed parameter system with time and space as independent parameters. The column modelling using appropriate basic equations, their application to binary systems, the solution scheme to the model equations and the distillation column simulation algorithm are described. The heat pump simulation algorithm is then coupled with this algorithm and the column transient behaviour with and without heat pump assist is obtained. The results are compared with earlier steady state data in the literature.

ISSN:0363-907X    

DOI:10.1002/er.4440150207

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

年代:1991

数据来源: WILEY

ISSN:0363-907X    

DOI:10.1002/er.4440150201

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

年代:1991

数据来源: WILEY