Two building factors-a longer thermal lag of more than one hour for building envelops and a lag of indoor radiation to convert into cooling load-have impact on the instantaneous heat input and instantaneous cooling lo...Two building factors-a longer thermal lag of more than one hour for building envelops and a lag of indoor radiation to convert into cooling load-have impact on the instantaneous heat input and instantaneous cooling load.So the two factors should be taken into account when selecting the weather parameters for air-conditioning system design.This paper developed a new statistic method for the rational selection of coincident solar irradiance,dry-bulb and wet-bulb temperatures.The method was applied to historic weather records of 25 years in Hong Kong to generate coincident design weather data.And the results show that traditional design solar irradiance,dry-bulb and wet-bulb temperatures may be significantly overestimated in many conditions,and the design weather data for the three different constructions is not kept constant.展开更多
Air conditioning design has become an interesting aspect of human life with the aim of seeking environmental comfort for indoor spaces. Analytical work involves in the design of air-conditioning system is often time c...Air conditioning design has become an interesting aspect of human life with the aim of seeking environmental comfort for indoor spaces. Analytical work involves in the design of air-conditioning system is often time consuming and laborious. This work therefore aims at developing a visual interactive computer package for the design of air conditioning system using the international conference centre, University of Ibadan, Nigeria as a case study. Procedures for calculating heat gain through various building components were discussed in detail. Cooling load analysis was carried out using standard cooling load equations obtained from the American Society of Heating, Refrigeration and Air conditioning Engineers (ASHRAE) handbook. A computer program was developed using java programming language to compute the total cooling load in the building. The result from the computer program was obtained within a very short period of time when compared with that of the manual one. The cooling load of the building obtained was 3,194,414 btu/hr;a visual interactive computer package for the design of air conditioning system has been developed and tested positively;hence can be used to design air conditioning system for any building.展开更多
Selection of air conditioning(AC) cold/heat sources generally concerns about certain aspects and cannot reveal the whole profile of the problems. Grey relation analysis (GRA) is a data processing method to categor...Selection of air conditioning(AC) cold/heat sources generally concerns about certain aspects and cannot reveal the whole profile of the problems. Grey relation analysis (GRA) is a data processing method to categorize the correlation extent of compared sequences and a certain reference sequence in a system with uncertain information. It is applied to evaluating and selecting AC cold/heat sources from four main aspects, which are technology, economy, reliability, and operation and management. Case study shows that the result for selecting AC cold/heat sources with the GRA method can be more reasonable and convincible. Thus it offers a new approach for designers in heating, ventilating and air conditioning field to compare and evaluate different AC cold/heat sou rces.展开更多
Based on the method of compound and additional conditions under the conditions of the equal temperature rise and the equal potential drop (P.D.) of resistance, the application of design software of dry-type air-core r...Based on the method of compound and additional conditions under the conditions of the equal temperature rise and the equal potential drop (P.D.) of resistance, the application of design software of dry-type air-core reactor is introduced in this thesis. The analytical methods of the inductance are also given. This approach is proved entirely feasible in theory through the simplification with Bartky transformation, and is able to quickly and accurately calculate reactor inductance. This paper presents the analytical methods of the loss of dry-type air-core reactor as well.展开更多
文摘Two building factors-a longer thermal lag of more than one hour for building envelops and a lag of indoor radiation to convert into cooling load-have impact on the instantaneous heat input and instantaneous cooling load.So the two factors should be taken into account when selecting the weather parameters for air-conditioning system design.This paper developed a new statistic method for the rational selection of coincident solar irradiance,dry-bulb and wet-bulb temperatures.The method was applied to historic weather records of 25 years in Hong Kong to generate coincident design weather data.And the results show that traditional design solar irradiance,dry-bulb and wet-bulb temperatures may be significantly overestimated in many conditions,and the design weather data for the three different constructions is not kept constant.
文摘Air conditioning design has become an interesting aspect of human life with the aim of seeking environmental comfort for indoor spaces. Analytical work involves in the design of air-conditioning system is often time consuming and laborious. This work therefore aims at developing a visual interactive computer package for the design of air conditioning system using the international conference centre, University of Ibadan, Nigeria as a case study. Procedures for calculating heat gain through various building components were discussed in detail. Cooling load analysis was carried out using standard cooling load equations obtained from the American Society of Heating, Refrigeration and Air conditioning Engineers (ASHRAE) handbook. A computer program was developed using java programming language to compute the total cooling load in the building. The result from the computer program was obtained within a very short period of time when compared with that of the manual one. The cooling load of the building obtained was 3,194,414 btu/hr;a visual interactive computer package for the design of air conditioning system has been developed and tested positively;hence can be used to design air conditioning system for any building.
文摘Selection of air conditioning(AC) cold/heat sources generally concerns about certain aspects and cannot reveal the whole profile of the problems. Grey relation analysis (GRA) is a data processing method to categorize the correlation extent of compared sequences and a certain reference sequence in a system with uncertain information. It is applied to evaluating and selecting AC cold/heat sources from four main aspects, which are technology, economy, reliability, and operation and management. Case study shows that the result for selecting AC cold/heat sources with the GRA method can be more reasonable and convincible. Thus it offers a new approach for designers in heating, ventilating and air conditioning field to compare and evaluate different AC cold/heat sou rces.
文摘Based on the method of compound and additional conditions under the conditions of the equal temperature rise and the equal potential drop (P.D.) of resistance, the application of design software of dry-type air-core reactor is introduced in this thesis. The analytical methods of the inductance are also given. This approach is proved entirely feasible in theory through the simplification with Bartky transformation, and is able to quickly and accurately calculate reactor inductance. This paper presents the analytical methods of the loss of dry-type air-core reactor as well.