Device and method for simulating working environment of draught fan and measuring air volume of draught fan during train running

Abstract

The invention discloses a device for simulating the working environment of a draught fan and measuring the air volume of the draught fan during train running. The device comprises a draught fan, a connecting pipeline and a wind tunnel with air circulation in an inner cavity, a wall surface of the wind tunnel is provided with an air inlet hole and an air outlet hole. An air inlet of the draught fanis communicated with the inner cavity of the wind tunnel through the air inlet hole, an air outlet of the draught fan is connected with one end of the connecting pipeline, the other end of the connecting pipeline is communicated with the inner cavity of the wind tunnel through the air outlet hole, and the connecting pipeline is provided with a measuring meter used for detecting the flow of air passing through the connecting pipeline. The invention further discloses a method for measuring the air volume of the draught fan through the device, the environment during train running is simulated byadjusting the air flow speed of the wind tunnel, and then the air volume is measured through the measuring meter. The train running environment can be simulated in a wind tunnel experiment, the air volume of the draught fan working in the environment can be accurately measured, a large number of probes do not need to be installed at an outlet, an inlet and the interior of the fan, and an internalflow field of the draught fan cannot be interfered.

Description

technical field [0001] The invention belongs to the technical field of wind tunnel experiments, and in particular relates to a device and method for simulating the working environment of a fan when a train is running and measuring the air volume of the fan. Background technique [0002] The comfort of high-speed trains has always been one of the frontier issues of train aerodynamics at home and abroad, and whether the air-conditioning system can work normally is the core issue related to the safety of high-speed trains, especially the comfort. Whether the air conditioning system can work normally depends on whether the air volume of the condensing fan meets the requirements. If the condenser cannot work normally, the air conditioner will stop running, which will seriously affect the safety and comfort of the train. The air volume of the condensing fan of the air conditioner needs to be measured on the air volume of the condensing fan of the train air conditioner. [0003] A...

AI Technical Summary

Problems solved by technology

The advantage of static measurement is that a long DC flow cover can be added, the direction of the wind speed inside the cover is consistent with the direction of the cover, and the measurement accuracy is high; the disadvantage is that it cannot consider the impact of the actual operation of the train. The horizontal grille will cause a negative pressure area, and at the same time, the interaction between the free flow and the condensed wind discharged from the air outlet will generate a positive pressure area above the air outlet. These two factors work together to increase the pressure difference on both sides of the fan, and As an axial flow fan, the condensing fan is relatively sensitive to pressure changes, and the air volume of the fan will change significantly after being affected by the increased pressure difference

The advantage of the second method of dynamic real vehicle measurement is that the influence of the operating environment is considered, but the flow cover cannot be installed, and the wind speed can only be measured at the inlet, outlet and inside, but the wind direction at any position in actual operation is unknown, especially the outlet There is a vortex in the internal flow field between the inlet and the inlet, and it is difficult to accurately measure the wind speed and direction even with a seven-hole probe, and a large number of seven-hole probes will interfere with the measured flow field, resulting in large errors

[0004] To sum up, there is currently no good way to accurately measure and evaluate the air volume of the condensing fan when the train is running normally, especially for high-speed trains with a speed of 350km / h and above, the design power of the fan can only be increased to ensure that the air conditioner normal operation, but there is no experimental basis for how much to increase

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