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Calculation-experimental substantiation of effective work for an evaporator in the self contained air conditioner

DOI: 10.17586/1606-4313-2024-23-2-22-29
UDC 697.975.4

Calculation-experimental substantiation of effective work for an evaporator in the self contained air conditioner

Dmitriev Denis O., Sulin A.B., Poltoratsky Maxim I.

For citation: Dmitriev D.O., Sulin A.B., Poltoratsky M.I. Calculation-experimental substantiation of effective work for an evaporator in the self contained air conditioner. Journal of International Academy of Refrigeration. 2024. No 2. p.22-29. DOI: 10.17586/1606-4313-2024-23-2-22-29

Abstract
The article examines the effect of unevenness in the field of air flow velocities impinging on the front section of a direct-boiling tubular-fin evaporator on the cooling capacity of an air conditioning unit. A mathematical modeling was carried out to calculate the characteristics of the evaporator with uneven airflow using specialized software packages, and an experimental study was conducted to confirm the simulation result. It has been established that the unevenness of the air flow pressure field and incorrect operation of the thermostatic valve lead to the discrepancy between the declared performance and the real one in the evaporator. In order to increase the performance of the evaporator, a new schematic solution for the distribution of refrigerant in the pipe passages was proposed and modeling of the operating parameters of a heat exchanger with a modernized configuration was carried out at a non-perpendicular angle of attack of the air flow. The results of mathematical modeling were confirmed expirementally and it was found out that the performance of the unit after modernization corresponds to that declared by the producer. The proposed solution does not lead to an increase in the overall dimensions of the unit or to the changes in other components of the system. The described technique for improvement the evaporator pipe passages has been successfully applied to other standard sizes of the self containedmarine air conditioners.

Keywords: evaporator, air cooler, uneven air flow, self contained air conditioner.

All references

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