CN-116428774-B - Air-cooled oil-cooled double-combined condenser with efficient heat exchange and heat exchange control method thereof

Abstract

The invention relates to an air-cooled oil-cooled double-combined condenser with efficient heat exchange and a heat exchange control method thereof, which solve the defect of poor heat exchange effect of the condenser compared with the prior art. The electric heating assembly comprises a refrigerating oil pipeline loop, an electric heating device is arranged on the refrigerating oil pipeline loop, the refrigerating oil pipeline loop is arranged at the bottom of the condenser body in a surrounding mode, an inlet of the refrigerating oil pipeline loop is connected to an A port of a tee joint, an outlet of the refrigerating oil pipeline loop is connected to a B port of the tee joint, and an oil filling nozzle is arranged on a C port of the tee joint. The invention utilizes the special structure of the condenser, combines the air flow characteristic and the liquid-state refrigerant characteristic of the gas in the U pipe, and sets the independent refrigerating oil structure, thereby reducing the space range, reducing the cost, improving the oil cooling heat exchange mode of the air-cooled condenser heat exchange weak area and realizing the bidirectional heat exchange.

Inventors

• SUN YUXIANG
• WANG ZHONGCHAO
• GUO WEIBIN
• ZHU LILIN
• WANG DONGDONG
• LI MIN
• WANG LU
• CAO HUIBIN
• WANG DAQING
• JIANG MAN
• GAO LIFU
• CHEN SHANGYUN

Assignees

• 中国科学院合肥物质科学研究院

Dates

Publication Date

20260512

Application Date

20230109

Claims (2)

1. 1. The heat exchange control method of the air-cooled oil-cooled double-combined condenser with efficient heat exchange comprises a condenser body (4), wherein an electric heating component is arranged at the bottom of the condenser body (4), the electric heating component comprises a refrigerating oil pipeline loop (3), an electric heating device (5) is arranged on the refrigerating oil pipeline loop (3), the refrigerating oil pipeline loop (3) is arranged at the bottom of the condenser body (4) in a surrounding mode, an inlet of the refrigerating oil pipeline loop (3) is connected to an A port of a tee joint (2), an outlet of the refrigerating oil pipeline loop (3) is connected to a B port of the tee joint (2), an oil filling nozzle (1) is arranged on a C port of the tee joint (2), a sensor (6) is arranged on a top cover at the top of the condenser body (4), and the refrigerating oil pipeline loop (3) is led to the top of the condenser body (4) in a surrounding mode through the bottom of the condenser body (4), and the heat exchange control method is characterized by comprising the following steps of: 11 If the condenser is in the heating mode, the electric heating component is turned off; 12 If the heating mode is adopted, the outdoor temperature t0 is less than or equal to 5 ℃ through monitoring of a sensor (6), and if the outdoor temperature t0 is less than or equal to 5 ℃, the electric heating component is turned off; 13 If the outdoor temperature t0 is less than or equal to 5 ℃, detecting whether the condenser unit is frosted or not through a sensor (6) at intervals of 5 minutes after the condenser unit is heated and operated for 30 minutes; 14 If the condenser unit is frosted, starting the electric heating assembly, calculating the oil injection quantity, and carrying out oil injection heating on the electric heating assembly according to the calculated oil injection quantity; the calculation of the oil filling quantity comprises the following steps: 141 Setting the current outdoor highest temperature as tmax, the maximum heat exchange capacity of the condenser as Q, and the highest exhaust temperature of the compressor as t; 142 Setting the heat exchange quantity of the bottom branch of the condenser to be Q/n, wherein n is the branch number of the condenser; 143 In the closed space, simulating and measuring the comprehensive heat exchange coefficient c of the refrigeration oil structure to the bottom branch condenser; 144 The oil injection quantity M is set to be larger than 1/2 of the U pipe volume V of the refrigerating oil pipeline, namely M is larger than or equal to 1/8 pi d2L, and the oil injection quantity M is set to be smaller than 3/4 of the U pipe volume V of the refrigerating oil pipeline, namely M is smaller than or equal to 3/16 pi d2L, wherein d is the inner diameter of the U pipe, and L is the length of the long U pipe; 145 The oil injection amount M of the condenser is calculated according to the following calculation formula: M =(Q/n)/[c*(tmax-t)]; if the oil filling quantity M is less than 1/2V, filling is carried out according to 1/2V, so that the reliable operation of the electric heating device (5) is ensured; if the oil filling quantity M is more than 3/4V, the refrigerating oil pipeline is at least 2 paths, and the filling quantity of each path is not lower than 1/2V.
2. 2. The heat exchange control method of the air-cooled oil-cooled double-combined condenser with efficient heat exchange according to claim 1, wherein the method for determining the comprehensive heat exchange coefficient is as follows: 21 Based on the condenser body (4), filling half of refrigerating oil into the bottom refrigerating oil pipeline and the U pipe above the bottom refrigerating oil pipeline respectively; 22 In a closed laboratory, a plurality of thermocouples are uniformly arranged at the bottom of the U-shaped pipe at the upper part, an electric heating device (5) is started, and the thermocouples are utilized to measure the average temperature difference before and after according to the principle that the power consumption is about the total heat absorption amount in a specified time, so that the heat exchange coefficient c1 of the refrigeration oil structure to the bottom branch condenser is calculated and obtained; 23 Adding the frozen oil to 3/4 of the U pipe volume V of the pipeline, and calculating and obtaining the comprehensive heat exchange coefficient c2 of the frozen oil structure to the bottom branch condenser; 24 Taking the intermediate value of c1 and c2 as the comprehensive heat exchange coefficient c of the refrigeration oil structure to the bottom branch condenser.

Description

Air-cooled oil-cooled double-combined condenser with efficient heat exchange and heat exchange control method thereof Technical Field The invention relates to the technical field of condensers, in particular to an air-cooled oil-cooled double-combined condenser with efficient heat exchange and a heat exchange control method thereof. Background In the air-conditioning refrigeration equipment on the market at present, the air-conditioning refrigeration equipment is commonly a tube-fin condenser, high-temperature and high-pressure refrigerant vapor at the exhaust position of a compressor enters the tube-fin condenser to be condensed and liquefied, and the heat of the refrigerant is released into the air to achieve the purpose of cooling. However, the traditional tube-fin condenser adopts a circular coil (with a circular radial section) and fins (with circular perforations) sleeved on the coil, and exchanges heat of medium in the tube with outside air so as to achieve the purpose of heat dissipation, and the heat is mainly taken away by air when the fins blow. The traditional condenser adopts round pipes, and on the air heat exchange side outside the pipe, the air from the windward side passes through the round pipes, so that the windward side area of the round pipes is large, the air resistance is large, more power consumption of the ventilator is required to be consumed, and meanwhile, the windward side area of the round pipes is large, vortex exists on the leeward side of the round pipes, so that dead angles which cannot be blown by wind exist on the leeward part of the round pipe coil, the heat exchange effect of the air side outside the pipe coil is seriously influenced, and the heat exchange efficiency is lower. On the heat exchange side of the refrigerant in the tube, the refrigerant in the tube of the traditional single-inlet single-outlet condenser is in condensation phase change, the refrigerant just entering the condenser is gas, the density of the gas is small, the flow velocity is higher, the refrigerant is in a turbulent state, the heat exchange between the refrigerant and the inner wall of the heat exchange tube is strong and vigorous, the heat exchange coefficient is high, the refrigerant is phase-changed after being condensed by a part of the heat exchange tube, the refrigerant is gradually changed into liquid, the density is increased, the flow velocity is reduced, even the refrigerant is reduced in a laminar state, the heat exchange between the refrigerant and the wall of the heat exchange tube is weakened, and the heat exchange coefficient is gradually reduced. The traditional single-inlet and single-outlet condenser has the problems that the heat exchange coefficient is gradually reduced due to the gradual reduction process of the refrigerant caused by phase change in the tube and the overall heat exchange coefficient is not high in the aspect of heat exchange in the tube, and the air resistance is larger and more power consumption of the ventilator is required due to the fact that air from the windward side passes through a plurality of rows of circular tubes in the aspect of heat exchange outside the tube. Therefore, on the whole, the traditional single-inlet single-outlet circular tube condenser has large air resistance and low heat exchange efficiency, the multi-connected outer machine condenser adopts air-cooled heat exchange, the U tube at the bottommost end of the fin type copper tube heat exchanger is shielded by the chassis folded edge and combined with the air flow characteristic generated by the rotation of the fan, the heat exchange effect is relatively poor, the heat exchange mode is single and low in efficiency, the problem of the overall energy efficiency of the air conditioner is reduced, and the integral energy efficiency improvement of the air conditioner is not facilitated. Therefore, further improvements are needed. In addition, the condenser utilizes the floating force action principle, the design of 'lower liquid inlet and upper air outlet' is adopted, the frosting condition of the condenser can also occur in winter, and particularly, the bottom of the condenser is particularly prominent. The condensing unit is used for refrigerating, and in the refrigerating process, the fins of the evaporator are frosted, so that the refrigerating efficiency of the condensing unit is affected after frosting, and the evaporator is required to be frosted. In general, the running time of the compressor is counted by a timer, when the time reaches a certain threshold value, the compressor is disconnected for refrigeration, the electric heating defrosting module is turned on, and the refrigerator returns to the refrigerating state of the compressor again after the defrosting is completed. However, the existing defrosting mode cannot defrost according to the actual frosting condition of the evaporator fins, the defrosting time is relatively early, energy is wasted, or the defrosting time i