DYNAMIC AND THERMAL INTERFERENCE EFFECTS ON TWO NEIGHBOURING BUILDING MODELS

The paper considers the dynamic and thermal interference effects on two neighbouring building models in the form of square prisms arranged at a short distance from each other. It is shown how relative positions of the models affect the specific phenomena caused by the airflow interactions.The aim of this paper is to experimentally study the dynamic and thermal interference of a tandem of two building models in the form of square prisms depending on their relative position.The phenomenon of wind loads on buildings and structures has always attracted great interest among engineers and researchers. With the accumulation of knowledge and technical capabilities, the potential for likely ways to study wind flows and their impact on different objects increased. In recent years, the world science has accumulated an extensive knowledge base on wind impacts on objects of various shapes, such as prisms, pyramids, cylinders, etc. Studies are carried out for their mutual impact of several objects on changes in both the wind load and heat exchange. Their mutual effect on the air motion and turbulence is considered.There are two main areas in the field of the wind impact. The first impact is the force load on building, the second is the wind as a source of convective heat exchange. The object of this study is the interference parameters allowing to assess the influence on the field of pressure and heat recoil of disturbances evoked in front of the barriers.At the first stage, physical models help to study the pressure field on different facets and ratios of the local and medium heat exchange under the forced convection conditions. The next step is to jointly consider the wind (dynamic) load and heat flows, attempting to detect the total contribution to changes depending on the reciprocal model arrangement. All experiments are performed in the aerodynamic tube, at the TSUAB department. It is shown that the dynamic and thermal interference ratios vary greatly in two building models. At the same time, the thermal interference is very conservative compared to the dynamic. Using the interference parameters, it is easy to analyze the extreme pressure and the heat flow on the model surface depending on a large number of factors, including their arrangement.

STUDY OF THERMAL INTERFERENCE OF ELEMENTS OF THE UNDERGROUND HEAT EXCHANGER IN ELECTROLYTIC BATH

A study was made of the mutual thermal eff ect of the tube elements of soil heat exchangers. It was determined that the number of pipe elements of the soil heat exchanger has the greatest eff ect on the amount of heat infl ux from the soil mass. It is established that when placing the pipe elements at a distance of one diameter from each other, it causes a signifi cant decrease in the heat infl ux to the soil heat exchanger. Increasing the distance between the pipes reduces the thermal interference of the elements. The coeffi cients of thermal interference are found for various confi gurations of ground heat exchangers, which depending on the number of pipes and the distance between them vary from 0.621 to 0.99.

Optimal Sizing of Irregularly Arranged Boreholes Using Duct-Storage Model

As the sizing of borehole heat exchangers (BHEs) is crucial for ground-source heat pump systems, which are becoming increasingly complex and diverse, novel sizing tools are required that can size both boreholes and connected systems. Thus, an optimization-based sizing method that runs in TRNSYS with other component models is proposed. With a focus on the feasibility of the method for typical BHEs, the sizing of irregularly placed boreholes using the well-known duct-storage (DST) model that inherently cannot describe irregular borefields is examined. Recently developed modification methods are used for the DST model. The proposed sizing method is compared with the existing ground loop heat exchanger (GLHE) sizing program. The results indicate that the proposed method has a genuine difference of approximately 3% compared with the GLHE, and the difference increases with the thermal-interference effects. A regression-based method selected to modify the DST model for describing irregular borefields exhibits acceptable sizing results (approximately 5% for test cases) despite the genuine difference. This study is the first to use the DST model for sizing BHEs under irregular borefield configurations, and the tests indicated acceptable results with an approximate difference of one borehole among a total of 30 boreholes in the test cases.