Analysis of Smart Zone Heating in Different Heating Systems

The basic concept in the design of buildings with zero energy consumption is, in addition to high-quality thermal properties of the building envelope, also a correct and efficient system of heating and hot water preparation in residential buildings. One of the basic concepts when designing heating systems is a zone heating system. It is a system that brings effective regulation according to heating zones. In practice, the question sometimes arises as to whether zone regulation of individual rooms in small family houses is necessary. That is whether in such buildings, zone heating is not an unnecessary investment cost. In this paper, we analyze the effect of zone heating in two types of heat transfer systems on the internal operating temperature in the individual analyzed zones, which are interconnected by an internal partition structure. It is a verification that even in smaller spaces, zone heating has a significant potential for energy savings.

REDUCTION OF EXTERNAL NOISE VEHICLE of SPAI “BOHDANA” ON THE BASIS OF THE KrAZ-63221 IMPROVED TWO-CHAMBER REACTIVE NOISE SILENCER

High-quality military equipment is a vital necessity for the independent state of Ukraine, especially in the conditions of aggravation of the situation at the front. One of the parameters that determines the quality of military vehicles is the level of external noise. The external noise of this type of car, in addition to the negative impact on human health (including the crew), is also an unmasking factor. In order to reduce the level of external noise of SPAI “Bogdan” on the basis of the chassis KrAZ-63221, the use of an advanced two-chamber jet muffler of the exhaust gases of the internal combustion engine is proposed. The known two-chamber jet muffler of exhaust gases has a fixed internal partition. Its acoustic efficiency is described by a known formula. It is proposed to make the inner partition of the muffler movable. This need arises from the fact of constant changes in the speed of the engine crankshaft during the movement of the car. The change in the position of the inner partition is consistent with the change in the speed of the crankshaft, because these two processes are synchronized. The mathematical package IDL was used to analyze the known formula for the efficiency of a two-chamber jet exhaust muffler of an engine with a movable inner partition. Given the need to show the dependence of the efficiency of the muffler simultaneously on two parameters – the speed of the crankshaft and the position of the movable inner partition of the muffler – the method of color coding was chosen. The design of a two-chamber jet noise muffler developed for ACS “Bogdan” is given. As a result of introduction of the developed muffler noise reduction of level of external noise of the SPAI “Bogdan” on the basis of the chassis KrAZ-63221 car on 2–3,5 dBA in the range of speeds of movement of 45–85 km/h is forecasted.

The Effect of Subgrade Coefficient on Static Work of a Pontoon Made as a Monolithic Closed Tank

This article presents the effect of taking into account the subgrade coefficient on static work of a pontoon with an internal partition, made in one stage and treated computationally as a monolithic closed rectangular tank. An exemplary pontoon is a single, ready-made shipping element that can be used as a float for a building. By assembling several floats together, the structure can form a floating platform. Due to the increasingly violent weather phenomena and the necessity to ensure safe habitation for people in countries at risk of inundation or flooding, amphibious construction could provide new solutions. This article presents calculations for a real pontoon made in one stage for the purpose of conducting research. Since it is a closed structure without any joint or contact, it can be concluded that it is impossible for water to get inside. However, in order to exclude the possibility of the pontoon filling with water, its interior was filled with Styrofoam. For static calculations, the variational approach to the finite difference method was used, assuming the condition for the minimum energy of elastic deflection during bending, taking into account the cooperation of the tank walls with the Styrofoam filling treated as a Winkler elastic substrate and assuming that Poisson’s ratio ν = 0. Based on the results, charts were made illustrating the change in bending moments at the characteristic points of the analysed tank depending on acting loads. The calculations included hydrostatic loads on the upper plate and ice floe pressure as well as buoyancy, stability and metacentric height of the pontoon. The aim of the study is to show a finished product—a single-piece pontoon that can be a prefabricated element designed for use as a float for “houses on water”.

Testing Crack Resistance of Non-Load-Bearing Ceramic Walls with Door Openings

Cracking in non-load-bearing internal partition walls is a serious problem that frequently occurs in new buildings within the short term after putting them into service or even before completion of construction. Sometimes, it is so considerable that it cannot be accepted by the occupiers. The article presents tests of cracking in ceramic walls with a door opening connected in a rigid and flexible way along vertical edges. The first analyzes were conducted using the finite element method (FEM), and afterward, the measurements of deformations and stresses in walls on deflecting floors were performed on a full scale in the actual building structure. The measurements enabled to determine floor deformations leading to cracking of walls and to establish a dependency between the values of tensile stresses within the area of the door opening corners and their location along the length of walls and type of vertical connection with the structure.

Natural Building Materials for Interior Fitting and Refurbishment—What about Indoor Emissions?

Indoor air quality can be adversely affected by emissions from building materials, consequently having a negative impact on human health and well-being. In this study, more than 30 natural building materials (earth dry boards and plasters, bio-based insulation materials, and boards made of wood, flax, reed, straw, etc.) used for interior works were investigated as to their emissions of (semi-)volatile organic compounds ((S)VOC), formaldehyde, and radon. The study focused on the emissions from complete wall build-ups as they can be used for internal partition walls and the internal insulation of external walls. Test chambers were designed, allowing the compounds to release only from the surface of the material facing indoors under testing parameters that were chosen to simulate model room conditions. The emission test results were evaluated using the AgBB evaluation scheme, a procedure for the health-related evaluation of construction products and currently applied for the approval of specific groups of building materials in Germany. Seventeen out of 19 sample build-ups tested in this study would have passed this scheme since they generally proved to be low-emitting and although the combined emissions of multiple materials were tested, 50% of the measurements could be terminated before half of the total testing time.

THE EFFECTS OF INTERNAL PARTITION ON INDOOR DAYLIGHTING PERFORMANCE OF STUDENT RESIDENTIAL BUILDING IN IPOH, PERAK

The installation of an internal partition has resulted in lowering the illumination level inside a building. Therefore, this study is intended to evaluate the effects of several internal partition layout on indoor daylighting performance in student residential rooms. Several options of internal partition were simulated using Climate Based Daylight Modelling (CBDM) to suggest the effective partition layout to overcome low daylighting level inside the room at the annual level. The findings indicate that the internal partition perpendicular to the window layout has been proven to have the highest annual daylight sufficiency in a student residential room in the tropics.

Performance Assessment of a Triangular Integrated Collector Using Neural Networks

A numerical study is achieved on a new shape of temperature saver solar collector using an artificial neural network. The storage collector is a triangle face and a right triangle pyramid for the volumetric shape. It is obtained by cutting a cube from one upper corner at 45°, down to the opposite hypotenuse of the base of the cube. The numerical study was carried out using the computational fluid dynamics code (ANSYS-Fluent) software with natural convection phenomenon in the pyramid enclosure. Elman backpropagation network is used for his ability to find the nearest solution with the smallest error rate. The network consists of three layers, each of different corresponding weights. The results show that the temperature and velocity distributions throughout the operating period were obtained. The influence of introducing an internal partition inside the triangular storage collector was investigated. Also the optimum geometry and location for this partition were obtained. The enhancement was best at y = 0.25 m, whereas the height of triangular collector was 0.5 m. The hourly system performance was evaluated for all test conditions. The performance of the NN to train a model for this work was 0.000207, while the error of the calculation was 1×10-2 as average.

STRUCTURAL FEATURES OF THE CHAMBER GRAVES OF THE VIKING AGE IN THE MIDDLE DNIEPER REGION

The basic structural elements of the chamber tombs of the 10th — beginning of 11th century from the territory of the Middle Dnieper are considered in the paper. The special features make possible to reconstruct their connection with the funeral traditions of other regions of Northern and Eastern Europe. Literary sources confidently point that the burial chamber semantically symbolized the home in which the deceased «settled». Like the synchronous residential buildings, the burial chambers had either a log cabin or frame pillar structure. The first of them were more widespread in the territory of Rus, the second one — in Scandinavia. The upper cover was obligatory that mimicked the roof of the house and provided free, empty space inside the chamber. In some cases, the board floor remnants were occurred, sometimes the boards lied on the transverse logs. In addition, the internal partition of the chambers sometimes can be traced, usually related to the accompanying burial of horse. Above the chamber the mound was built, the size of which depended on the social status of the deceased. In Kiev the chamber rite gradually acquired some specific features, such as the felling of the walls of tombs «in the roundabout» and the cover of tombs by overhead logs. These features make the Kiev and Pskov necropolises related and allow suggests that there were cases of purposeful resettlement of the part of Kyiv elite in northwestern Rus near the third quarter of the tenth century. In return, Shestovitsa demonstrates the closest connection to the Scandinavian Peninsula and Birka in particular. This relationship was revealed itself by the presence of soil steps for the concomitant horse burials and a high percentage of frame pillars in the chambers. The appearance within the tombs of additional element — the movable coffin — illustrates the spread of Christian ideology.