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Abstract

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Introduction

On a background the total offensive of warm buildings and heat-pumps in America, Asia and Europe Ukraine looks the island of cold buildings and out-of-date boiler rooms and TEC. Hasty and permanent growth of prices on natural gas during many years did economic helpless systems of centralized teplosnabzheniya of Ukraine. In investigation what gas began to oust itself - at first from industry, and then and from ZHKKH. High prices on natural gas did economic expedient plenty of projects of his substitution a local fuel and energy. One of very perspective directions is mass modernization of buildings and systems of teplosnabzheniya.

1. Purpose and tasks

A research purpose is development more of the efektivnogo use of heat-pumps, which will allow substantially to decrease thermal losses in dwellings and budgetary buildings.

2. Research review

For diminishing of thermal losses such decisions are used in dwellings and budgetary houses:

2.1 Use of flat sun collectors

Sun collector collect thermal energy of a Sun and heat material-teplonositel'. This device befits for the decision of a number of domestic and production tasks: for a hot water-supply, heating of building, heating of water in a pool. Sun collectors are vacuum and flat. In this research the flat is used sun kolektor.

A flat sun collector is the most widespread type. He consists of aluminium corps which selective coverage is located into, tubes give warmly and teplonositel' circulates in them. Lateral walls and bottom of collector have an isolating layer which diminishes teplopoteri in an environment. A sunlight passes through glazing and gets on a suctive plate which is heated, converting a sun radiation into thermal energy. It is warmly passed to teplonositelyu - water or antifreeze, to circulatory through a sun collector. Teplonositel' is heated and gives after thermal energy through teploobmennik to water in a capacity waterheater. In him hot water is to the moment of its use. Also in a capacity waterheater it is possible to set an electric insertion, that in the case of drop in a temperature below set (for example, from a long gloomy weather) it dogrevala water to the set temperature. Principle of work of setting following: due to the location of flat collector 1 above the top level of tank-accumulator 2 on height of a 0,3 - 0,6 mcode hot water from a flat collector 1 in a tank-accumulator 2 peretekaet both under hydrodynamic pressure and under act of thermodiffusion. Before the start of setting, fill cold water a tank-accumulator 2, pipes z''ednuyut' tank-accumulator 2 with a flat collector 1. Then close all valves. In daylight saving time, since a 8.00 morning water begins to be heated in a flat collector 1. In 2-3 hours after the continuous irradiation of surface of flat collector and heating of water in him open valves 7 and 8 and warmed-up water from overhead part of collector 4, enters tank-accumulator 2, from there in a pipe for the serve of cold water 3. Process of circulation of water between a tank-accumulator 2 and by a flat collector 1 lasts to the increase of temperature in the underbody of tank-accumulator 2 and on the entrance of pipe for the serve of cold water 3 in a flat collector 1, to 65 - 80 °Ñ (338,15 - 353,15 Ê) (on occasion to 85 - 90 °Ñ (358,15 - 363,15 Ê)). After achievement of these temperatures, open a valve 9 and hot water acts to the user (and farther in time) of heating - in the radiators of apartment. Line for the serve of hot water, by termosifonnykh circulation of water, tack to the side of tank-accumulator 2 on a mark 3/4 his heights from lower basis.

Figure 1 - Chart of work of sun collector

Figure 1 – Chart of work of sun collector

1 is a flat collector; 2 is a tank-accumulator with a metering device; 3 is a pipe for the serve of cold water; 4 is a pipe for the serve of hot water; 5 is a reservoir for spare water; 6 is a ventiduct; 7 - 11 are valves, 12 is a line of weathering of water.

2.2 Use of sewages

The use of heat of sewage flows can shorten the expense of fuel-power resources and decrease the amount of extrass of contaminents.

Flows in dwellings buildings are second-working water from dushey washstands, toilets et cetera An amount and temperature (near 20°Ñ) of flows remain permanent in the flow of year, it does their user-friendly as low temperature teploistochnika for a heat-pump.

A research task is determination of efficiency of the use of teplonasosnogo equipment, working from the heat of flows for indemnification of the teplopotrebnosti system of heating. And also in determination by normative, technical literature, amount of flows, their temperature, comparison of amount of heat, producible TN from the teplopotrebnost'yu system of heating.

2.3 Use of thermosiphon

In the impermeably closed pipe which air is pumped out from, the two-bit of liquid is placed. Within the limits of temperatures 80-150 °Ñ usually as a working liquid (teplonositelya) water is used. At heating of lower end of such pipe (area of evaporation) there is evaporation of liquid and pair rises to the cold end (area of condensation), where and condensed. A runback under the action of gravity forces returns on the walls of pipe in the area of evaporation. At certain terms this process can take place skol' pleasingly long. Thus due to the hidden warmth of paroobrazovaniyal [kDzh/kg] there is a process of heat transfer. Because the hidden warmth of vaporization is great, even at the small difference of temperatures between the ends of thermosiphon he can pass the far of warmth.

2.4 Use of teploobmennika

Teploobmennik— device, in which a heat exchange is carried out between two teplonositelyami, having different temperatures.

Teploobmenik of type a pipe in a pipe behaves to the superficial thermal vehicles. He gotes from a few CPLD between itself links, and every link consists of two pipes which a superficial (through walls) heat exchange is between. Teploobmennik of type a pipe in a pipe is the simplest, in him there can teplonositelyami be both pair and gases and liquids. Such vehicle at the great number of dignities does not almost have failings.

Teploobmennik «pipe in a pipe» include a few elements located above each other, thus every element consists of two pipes: outward pipe of greater diameter and concentric located vnut-ri it pipes of less diameter. Inwardly the pipes of elements are united with each other consistently; similarly CPLD between itself naruzhnye. For a treatability inwardly pipes unite through removable kalatchs.

Due to a small crossrunner in these teploobmennikakh the high-rate of teplonositeley are easily arrived at in both in pipes and in interpipe space. At the fars of teplonositeley teploobmennik is made from a few parallel sections, bondable to the general collectors.

Teploobmenniki «pipe in a pipe» can be used, both for heating and for cooling. Heating is usually produced or by hot water or saturated aquatic steam which is started in interpipe space and condensed on-the-spot internal pipe.The use of aquatic steam as a warming agent has the followings dignities:

- high coefficient of heat emission;

- it is plenty of heat, selected during devaporation;

- it is evenness of heating, because devaporation takes place at a stationary temperature;

- it is the easy adjusting of heating.

At cooling in teploobmennikakh a «pipe in a pipe» as khladoagenta can be used river or artesian water, and in case, ko-gda it is required to get a temperature below 5-20°Ñ apply refrigeration rassoly (water solutions of ÑàÑl2, NaCl, and other).

Conclusion

In Ukraine long time the basic enemy of the systems of centralized teplosnabzheniya was an ordinary double-pressure gas boiler. By the basic destroyer of the centralized systems of teplosnabzheniya from 2015, probably, a housing not caldron, but heat-pump, will become. It is exactly fated this technology to give up for lost on direct incineration of fuel for teplosnabzheniya. As a combustion engine changed a steam engine at one time, so heat-pumps today oust caldrons from markets.

At writing of this abstract master's degree work is not yet completed. Final completion: December, 2014. Complete text of work and materials on the topic can be got for an author or his leader after the indicated date.

References

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  5. V.F. Gershkovich. Research of work of heat-pump, using the warmth of soil and sewage flows, in the hot water system. An energy-savings is in buildings ¹3-2007 (¹34).