Abstract
Heat pumps, which enable the cooling and heating of vehicular cabins, consume a significant portion of the total energy consumption in electric vehicles (EVs). The efficiency of the heat pump is typically degraded owing to cold-weather conditions, so the refrigerant-injection technique has been proposed for improving the system performance and compressor reliability. In this study, a simulation model for an R134a heat pump with vapor injection is developed and validated by performing thermodynamic analyses with geometrical information. The effects of the injection-port design are investigated using the developed numerical model. Single-injection and dual-injection ports are considered to optimize the coefficient of performance (COP) and isentropic efficiency by controlling the injection mass flow rate. The optimal angles of the single- and dual-injection ports are determined to be 440° and 535°/355° (for pocket A/B), respectively, while the corresponding COPs are improved by 7.5% and 9.8%, respectively, compared to the non-injection heat pump at an outdoor temperature of −10 °C.
| Original language | English |
|---|---|
| Pages (from-to) | 800-811 |
| Number of pages | 12 |
| Journal | Applied Thermal Engineering |
| Volume | 127 |
| DOIs | |
| Publication status | Published - 2017 Dec 25 |
Bibliographical note
Publisher Copyright:© 2017 Elsevier Ltd
Keywords
- Dual injection
- Electric vehicle
- Heat pump
- Injection port
- Vapor injection
ASJC Scopus subject areas
- Energy Engineering and Power Technology
- Mechanical Engineering
- Fluid Flow and Transfer Processes
- Industrial and Manufacturing Engineering
