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Article
Publication date: 14 September 2017

Hongtao LIU

In recent years, fast urban expansion in China has stimulated rapid energy consumption growth and increased environmental pollution. Therefore, it is important to utilize…

Abstract

Purpose

In recent years, fast urban expansion in China has stimulated rapid energy consumption growth and increased environmental pollution. Therefore, it is important to utilize clean and renewable energy in district heating for the sustainable urban development. This study aimed to investigate the environmental and economic impacts of one hot dry rock (HDR) geothermal energy-based heating system in a life cycle framework.

Design/methodology/approach

By using the input–output-based life cycle analysis model, the energy consumption, CO2 emission and other pollutants of the HDR-based heating system were evaluated and then compared with those of other four heating systems based on burning coal or natural gas. The life cycle costs of the HDR-based heating system were also analyzed.

Findings

The results showed that using HDR geothermal energy for heating can significantly reduce fossil fuel consumption, CO2 emission as well as environmental pollution, and its life cycle costs are also competitive.

Originality/value

This study not only evaluated the environmental and economic impacts of the HDR-based heating system in a life cycle framework but also provided a methodological life cycle assessment framework that can estimate both economic and environmental benefits, which can be used in policy making for China’s urban development.

Details

International Journal of Energy Sector Management, vol. 11 no. 4
Type: Research Article
ISSN: 1750-6220

Keywords

Article
Publication date: 3 December 2018

Hongbin Zhao, Yu Cao, Chang Liu and Xiang Qi

The purpose of this paper is to investigate the performance of coke oven gas (COG)-combined cooling, heating and power (CCHP) system and to mainly focus on studying the…

Abstract

Purpose

The purpose of this paper is to investigate the performance of coke oven gas (COG)-combined cooling, heating and power (CCHP) system and to mainly focus on studying the influence of the environmental conditions, operating conditions and gas conditions on the performance of the system and on quantifying the distribution of useful energy loss and the saving potential of the integrated system changing with different parameters.

Design/methodology/approach

The working process of COG-CCHP was simulated through the establishment of system flow and thermal analysis mathematical model. Using exergy analysis method, the COG-CCHP system’s energy consumption status and the performance changing rules were analyzed.

Findings

The results showed that the combustion chamber has the largest exergy loss among the thermal equipments. Reducing the environmental temperature and pressure can improve the entire system’s reasonable degree of energy. Higher temperature and pressure improved the system’s perfection degree of energy use. Relatively high level of hydrogen and low content of water in COG and an optimal range of CH4 volume fraction between 35 per cent and 46 per cent are required to ensure high exergy efficiency of this integration system.

Originality/value

This paper proposed a CCHP system with the utilization of coke oven gas (COG) and quantified the distribution of useful energy loss and the saving potential of the integrated system under different environmental, operating and gas conditions. The weak links of energy consumption within the system were analyzed, and the characteristics of COG in this way of using were illustrated. This study can provide certain guiding basis for further research and development of the CCHP system performance.

Details

World Journal of Engineering, vol. 15 no. 6
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 1 February 1971

We are growing accustomed to shock tactics of the US Administration in dealing with toxic residues in food or additives which are a hazard to man, as well as the daily…

Abstract

We are growing accustomed to shock tactics of the US Administration in dealing with toxic residues in food or additives which are a hazard to man, as well as the daily press infusing sensation, even melodrama, into them, but the recent action of the FDA in calling in from the food market several million cans of tuna and other deep sea fish because of the presence of mercury has had the worthwhile effect of drawing world attention to the growing menace of environmental pollution. The level of mercury in the fish is immaterial; it should never have been there at all, but it stresses the importance of the food chain in the danger to man and animal life generally, including fish beneath the sea. Without underestimating risks of pollution in the atmosphere from nuclear fission products, from particulate matter carried in the air by inhalation or even skin absorption, food and drink, which includes aqua naturale would seem to be the greatest danger to life. What these recent events illustrate in a dramatic manner, however, is the extent of pollution.

Details

British Food Journal, vol. 73 no. 2
Type: Research Article
ISSN: 0007-070X

Article
Publication date: 1 January 1961

During the design of the Atlas I.C.B.M. it was considered necessary to conduct full‐scale combined structural loading and aerodynamic heating tests for the purpose of…

Abstract

During the design of the Atlas I.C.B.M. it was considered necessary to conduct full‐scale combined structural loading and aerodynamic heating tests for the purpose of proving the ability of the nose adaptor and thrust barrel to withstand the combined effects of load and temperature. The following items were required to perform the tests: heating elements to radiate 450 sq. ft. of specimen area at a maximum rate of 10,000 B.T.U/sq. ft./hr., 1,500 KVA at 44 volts for six mins., controller, three variable pressure regulators for programming 3,000 lb./sq. in. hydraulic pressure to the loading cylinders, six‐channel programmer for varying heating and loading rates, a method for relating the capabilities of the equipment to the desired heat and load curves. Descriptions arc given of the heating equipment, heat controller, load controller, programmer, preliminary heat tests, preliminary load tests and test programmes as used by the Systems Test Laboratory of Convair‐Astronautics. As experience was gained by testing the need for preliminary tests was greatly reduced. The method described continues to be a valuable tool for performing full‐scale missile structural tests.

Details

Aircraft Engineering and Aerospace Technology, vol. 33 no. 1
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 1 March 1989

Bennett J. Price

This article discusses the basics of computer‐room air conditioning, an important component of the special environment required by mainframe computers and many…

Abstract

This article discusses the basics of computer‐room air conditioning, an important component of the special environment required by mainframe computers and many mini‐computers as well. Computer room air conditioners differ in some significant ways from “comfort” air‐conditioners, which are designed for the comfort of people rather than machines. These differences make it less than ideal to use air conditioning systems designed for human comfort for computer cooling. The author describes several different types of air‐conditioners, considerations related to the construction of a computer room, and factors that determine air‐conditioning requirements.

Details

Library Hi Tech, vol. 7 no. 3
Type: Research Article
ISSN: 0737-8831

Article
Publication date: 1 April 1947

Chester Street, Aston, Birmingham, 6. The ‘Donald’ Patent Barrel Lifter Truck and Stand, the three‐in‐one appliance. Barrels up to 7 cwts. lifted and transported by one…

58

Abstract

Chester Street, Aston, Birmingham, 6. The ‘Donald’ Patent Barrel Lifter Truck and Stand, the three‐in‐one appliance. Barrels up to 7 cwts. lifted and transported by one man. ‘Donald’ Patent Barrel Lifter Stands for Oil Stores.

Details

Aircraft Engineering and Aerospace Technology, vol. 19 no. 4
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 1 May 1982

As the cost of fuel rises, so the need to economise on its use becomes more important. In industry, fuel is used not only to drive machinery but also for heating

Abstract

As the cost of fuel rises, so the need to economise on its use becomes more important. In industry, fuel is used not only to drive machinery but also for heating industrial premises (and sometimes for cooling, for example in cold stores and in hot climates). Considerable saving of fuel used for heating, or for cooling, can be achieved by means of new technological innovations, in particular the use of microprocessors to control temperatures as well as the flow of hot water or cold or hot air.

Details

Industrial Management & Data Systems, vol. 82 no. 5/6
Type: Research Article
ISSN: 0263-5577

Article
Publication date: 6 February 2017

T. Javed, Z. Mehmood, M.A. Siddiqui and Ioan Pop

The purpose of this paper is to perform a numerical study for heat transfer through natural convection in the presence of a constant magnetic field in an incompressible…

Abstract

Purpose

The purpose of this paper is to perform a numerical study for heat transfer through natural convection in the presence of a constant magnetic field in an incompressible steady nanofluid flow inside an isosceles triangular cavity.

Design/methodology/approach

For this flow problem, the left wall of the cavity subjected to uniform/nonuniform heat was considered, while right and bottom walls of the cavity were kept cold. The obtained equations were solved by using the Galerkin weighted residual technique. Results are computed for a wide range of parameters including Rayleigh number (Ra) (10^3 < Ra < 10^7), Hartman number (Ha) (0 < Ha < 60), and heat-generation/-absorption coefficient (q) (−10 < q < 10), while, Prandtl number (Pr) was kept fixed at 6.2. These computed results are presented in terms of stream functions, isotherms, Nusselt numbers and average Nusselt numbers through figures.

Findings

It is observed that, in case of uniform heating of the side wall, the strength of stream lines’ circulations increases with an increase in Ra and decreases with an increase in Ha. Similarly, by increasing heat-absorption coefficient q, an increase in the circulation strength is noted and the circulation cell moves towards the left wall in the presence of a heat sink (q < 0) and moves to the cold right wall in the presence of a heat source (q > 0). In the case of nonuniformly heated left wall in the presence of a heat source (q > 0), a higher-temperature gradient is observed in the cavity and isotherms are clustered to the left wall in the lower portion and to right wall in the upper portion; these appear to be straight and parallel to the x-axis near the bottom wall. On the other hand, the heat transfer rate along all the walls of the cavity is observed to be higher for smaller values of q. Whereas, Nusselt number along the bottom wall (Nu-B) increases with an increase in the values of x, while, that along the left wall (Nu-L) first increases and then decreases. But Nusselt number along the right wall (Nu-R) is found to be qualitatively opposite to Nu-L with an increase in distance x. Whereas, average Nusselt number increases with an increase in Rayleigh number Ra and heat-generation/-absorption coefficient q.

Research limitations/implications

The problem is formulated for an incompressible flow; viscous dissipation has been neglected, negligible induced magnetic field has been considered and local thermal equilibrium has been considered.

Originality/value

Results presented in this paper are original and new for the effects of a uniform magnetic field on the natural convection of Cu–water nanofluid in a triangular cavity. Hence, this study is important for researchers working in the area of heat transfer in cavity flows involving the nanofluid to become familiar with the flow behavior and properties.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 27 no. 2
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 1 October 1995

Gregory R. Doddrell

Today, information technology is fundamental to the operation ofmost businesses, whether they are small companies or multinationalcorporations. In recent times, the…

1023

Abstract

Today, information technology is fundamental to the operation of most businesses, whether they are small companies or multinational corporations. In recent times, the implementation of local and wide area networks and the installation of computing equipment in office areas has brought information technology to nearly every working environment. The result is an increasing dependence on the availability, integrity and confidentiality of information stored and processed by these systems. As the trend shifts from “fortress” style central computer facilities to distributed systems located in generally less secure office environments, the risk of disruption increases, owing to lack of physical security, support services limitations and absence of site monitoring. The net result is higher business impact coupled with greater exposure. Identifies the elements that are at risk, discusses the issues businesses face when seeking to minimize exposures, suggests some practical solutions and describes some selected events that illustrate the hazards associated with having inadequate protection.

Details

Information Management & Computer Security, vol. 3 no. 4
Type: Research Article
ISSN: 0968-5227

Keywords

Article
Publication date: 1 June 1961

D.J. Leech

REFRIGERATION in aeroplanes does not, so far, involve the use of any techniques which have not already been established and used in other fields. These techniques must be…

Abstract

REFRIGERATION in aeroplanes does not, so far, involve the use of any techniques which have not already been established and used in other fields. These techniques must be considerably extended, however, and the features which distinguish this branch of refrigeration from others are that:

Details

Aircraft Engineering and Aerospace Technology, vol. 33 no. 6
Type: Research Article
ISSN: 0002-2667

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