Методика работы устройства, функционирующего без гидравлических ударов в системах кондиционирования

Abstract

RU: Рассматривается замена теплообменника высокого давления на гидрораспределитель и управление гидрораспределителем. Предлагается методика работы гидрораспределителя в системе кондиционирования рудничного воздуха глубоких шахт.

EN: Problem. In case high pressure heat exchanger is replaced by hydrodistributor the question of its running arises. The article proposes the method of hydrodistributor running proposed for utilization in the mine air conditioning system.

Literature review. Research workers of the Prydniprovs’ka State Academy of Civil Engineering and Architecture possess more than 20 author’s patents issued by the state ofUkraine for hydrodistributors. However, this article proposes a more updated hydrodistributor functioning without hydraulic impacts in normal conditions.

Aim. The article proposes the method of a device (hydrodistributor) operating without hydraulic impacts in air conditioning systems.

The investigation of hydraulic impact using electric model showed that hydraulic impacts that occur as a result of switching fluid currents in hydrodistributor can be technically controlled. In order to perform such control it is necessary to select hydraulic distributor that would allow to perform slow valve lock which would result in weak hydraulic impacts or would prevent them from occurrence.

Rubber [2] membranes should be replaced with movable insulating diaphragm whereas sealed tanks should be replaced with rather long pipelines with the amount of pipes increased up to six.

Operating schedule of this device is given in Picture 1. Pressure increase during hydraulic impact depends on the type of valve resistance fluctuation and is an effective tool used to soften hydraulic impact that depends on the selection of such valve closure time where the pressure does not exceed the acceptable level. The less the speed loss in the pipeline is, the smaller the pressure increase will be. The lower the speed of valve closure is, in other words, the shorter impact T phase is comparing to the time of full closure of the valve t3, the less the change in the valve closure degree would be according to Δα / D = T / t3 during each Δα / D phase. To ensure ongoing operation of the system during cold bearer supply it is proposed to accept a minimum amount of 6 tanks, three of which will function as a cold bearer supplier supplied to the processed horizon and the other three will return defrosted cold bearer to refrigerating machine (Picture 1b). In [1] with the coefficient of local valve resistance ξ =0,46 full closure of the valve is performed within 15 sec. With water velocity that equals to 1meter per second head loss in the valve are calculated to be 0,025 m. Insulating membrane covers the distance equal to the length of sealed tank one way per minute. Opening of the valve is performed within 15 seconds, closure will be performed within 15 seconds and the work for the fully closed valve will be performed within 30 seconds — the period will be 1 minute.

Reliability of the elements combination that the present system represents is determined depending on the reliability of each its element taking into consideration their effect on the system operation. Reliability of the system depends on its elements, their role and the type of reciprocal junction.

Conclusion.

1. The economy of heat during the application of the proposed hydraulic distributor in the system of cold bearer of mine air conditioning system distribution will make approximately 30–40 %.

2. With the application of proposed hydraulic distributor in the mine air conditioning system the technical effect lies in the fact that hydraulic impacts are eliminated, mine air conditioning system becomes simplified and more reliable.

3. In the process of choosing hydraulic distributor, its design and structure, the calculation of its performance reliability, graph illustrating conjugation of tanks functioning during liquid distribution (see Pic.1) was performed as well as utilization of total six tanks was decided. Three of them will accept cold bearer from the refrigerator situated at mine’s surface and the other three supply it to cooling in the bottomhole directly to air–cooling units. The system will function without hydraulic impacts.

4. In case high pressure heat exchanger is replaced by hydraulic distributor, total electricity economy according to the given costs will be more than UAH 1,5 million per year for one mine with the utilization of one air–cooling unit.