Finite time thermodynamic analysis and optimization of water cooled multi-spilit heat pipe system (MSHPS)

Abstract

• Energy saving in data centers is increasingly with the developing IT industry. • An accurate performance and evaluation model based on time cycle is proposed. • An periodic integral energy efficiency model is proposed. • The refrigerant flow distribution characteristic of MSHPS was built and tested. • The proposed method is fit for analysis of MSHPS and the real pipe-net systems. This study focuses on the heat transfer characteristics of the evaporation terminal, the cool distribute unit (CDU) and refrigerant flow distribution of a water cooled multi-spilit heat pipe system (MSHPS) used in data center. The finite time thermodynamic analysis, the exergy method and the software SIMULINK was employed to build the simulation model of the combined system. The results show that the IT servers should concentrate on arranging at the location below 1.3 m. The CDU has a heat transfer of about 74 J in a period of 6 s. And the optimum flow rate of the CDU is 0.82 kg/s. The flow distribution characteristic of a CDU which connect 2 heat pipe evaporator terminals of 6 kW was calculated, and the working fluid is R22. Then the free cooling time,part time free cooling and energy saving potential in major cities of China were analysised. The energy saving potential is from 61% to 25%. The results are of great significance for the operational control and practical application of a MSHPS and other pipe-net systems.