Experiments On The Flow-induced Vibration-enhanced Heat Transfer Performance Of A Plane-plate Heat Recovery Ventilator

With the increasingly improvement of people's living standard, air conditioners have been used widely for people's high living requirement, which resulted in a constant rise in consumption of energy sources. Energy saving has attracted more and more attention. The building energy consumption takes up 30%-40% of the total energy consumption in the developed countries, while nearly 30% of which was consumed by air conditioners. For saving energy, the building envelopes become tighter, which causes lower indoor air quality. So, massive fresh air is required to be provided indoor to improve the air quality which results in more energy usage. Fresh air heat exchangers are adopted to reclaim the energy contained in the waste air when fresh air is providedIn present market, the common energy saving and ventilation equipments, such as rotary heat exchanger, heat pipe, heat exchanger with thermal medium, plate fin heat exchanger etc. These have the shortcomings of cross contamination, high cost, low efficiency, high running cost, difficult maintenance, severe operating condition,big and heavy. In order to solve these problems, a new type fresh air heat exchanger which is made of cheap plastic was tried out. Lots of experimental results show that the heat transfer film vibrates under certain air flow rate, which can improve the heat transfer efficiency of the fresh air heat exchanger. But the mechanism of this heat transfer enhancement is complicated, so man-made incentive vibration was studied to understand the effect of amplitude and frequency on heat transfer efficiency, respectively. When vibration frequency is settled, the effect of vibration amplitude was studied; when vibration amplitude is settled, the effect of vibration frequency was studied.Large of experimental results show that: the heat transfer efficiency can be enhanced about 30% for the whole heat exchanger because of fluid-induced vibration, the heat transfer efficiency reach up to near 90%; the effect of the temperature difference of the cool in and the heat in on heat transfer efficiency decreases with the increasing of vibration frequency under certain vibration amplitude, when the temperature difference reaches about 18.0℃, the heat transfer efficiency tends to be the same. The heat transfer efficiency becomes high with the vibration amplitude under certain vibration frequency. The effect of vibration amplitude on heat transfer efficiency is more significant than the vibration frequency. All the work in the present paper will supply the basis for further optimization.