Research of an integrated cooling system consisted of compression refrigeration and pump-driven heat pipe for data centers

摘要

An integrated cooling system is developed for the environmental control of all-year-round running data centers with high heat load. The system is consisted of a vapor compression refrigeration unit connected with a separated heat pipe unit by an evaporative condenser. Based on the outdoor temperature, the system can operate on three modes: vapor compression mode, dual refrigeration mode and heat pipe mode. The cooling capacity of vapor compression unit is regulated via volume control of six paralleled scroll compressors, while that of heat pipe unit is adjusted by frequency conversion outdoor fan. The experimental results indicate that the cooling capacity of the system has a nearly constant value of 200 kW, and EER changes from 21.2 to 3.1 when the outdoor temperature increases from -5 degrees C to 45 degrees C. The theoretical calculation and analysis show that, compared with air cooling direct expansion unit and air cooling dual source chiller, the proposed system has the lowest annual energy consumption with highest energy efficiency. So it can be the preferred choice for all-year-round running data centers especially in regions with low average annual temperature. (C) 2019 Elsevier B.V. All rights reserved.