Falling film evaporator and control method

Abstract

The invention discloses a falling film evaporator and a control method. The falling film evaporator comprises a cylinder body. Multiple distributors are distributed at the upper portion of the interior of the cylinder body. The multiple distributors are connected in parallel, and a liquid inlet pipe of each distributor is connected with a main liquid inlet pipe. A flow meter and an electronic expansion valve are connected to the liquid inlet pipe of each distributor in series. Each flow meter is used for collecting a refrigerant flow signal of the corresponding liquid inlet pipe and sends thesignal to a control panel, and the control panel controls the opening degrees of all the electronic expansion valves according to the received flow signals. By means of the falling film evaporator andthe control method, the distributors which are connected in parallel are designed, the refrigerant flow meters and the electronic expansion valves are arranged on the liquid inlet pipes of the distributors, the control panel controls the opening degrees of the electronic expansion valves according to the flow signals sent by the flow meters, the refrigerant flow in all the distributors which areconnected in parallel is the same, refrigerant distribution is uniform, the heat exchange performance of the falling film type evaporator is improved, and the problem that refrigerant distribution ina large number of falling film type evaporators is not uniform in the prior art is solved.

Description

technical field [0001] The invention belongs to the technical field of air conditioning, and in particular relates to a falling film evaporator and a control method. Background technique [0002] At present, falling film evaporators in the market have been applied in small and medium cooling capacity chillers, but it is still difficult to use falling film evaporators to replace traditional flooded evaporators for large cooling capacity chillers (such as above 1000RT). The reason is that the refrigerant distribution area of ​​the falling film evaporator with large cooling capacity is large, and it is difficult for the distribution device of the gas-liquid two-phase flow evaporator to distribute the liquid refrigerant evenly on the surface of the large-area heat exchange tubes, which makes the partial exchange There is little or no refrigerant distribution on the surface of the heat pipe, and the surface of these heat exchange tubes is easily evaporated to form a dry surface, ...

AI Technical Summary

Problems solved by technology

[0003] The invention provides a falling film evaporator, which solves the problem of uneven refrigerant distribution in the prior art

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