Experimental assessment of the fluid charge distribution in an organic Rankine cycle (ORC) power system. (October 2020)

• Record Type: Journal Article
• Authors: Dickes, Rémi; Dumont, Olivier; Lemort, Vincent
• Is Part Of: Applied thermal engineering. Volume 179(2020)
• Publication Date: 2020-10
• Subjects: Charge -- Measurement -- ORC -- Fluid distribution -- Infrared -- Experiments; Heat engineering -- Periodicals; Heating -- Equipment and supplies -- Periodicals; Periodicals; 621.40205
• DOI: 10.1016/j.applthermaleng.2020.115689
• Languages: English
• ISSNs: 1359-4311

Abstract

Highlights: Load cells and an infrared camera are used to assess the fluid distribution in an ORC unit. An extensive experimental campaign including 330 steady-state points is conducted. Fluid distribution and temperature profiles in the heat exchangers are directly correlated. The evaporator charge requirement dictates the condenser and the liquid receiver operation. The ORC charge and the receiver size are key parameters to optimize the system performance. Abstract: This paper reports on experiments aiming to understand and to characterize how the working fluid spreads in an organic Rankine cycle (ORC) power system. To this end, a 2- kW e ORC test rig is constructed and tested over a wide range of conditions. Besides standard thermo-hydraulic sensors, the fluid charge distribution is measured on-line by bending load cells and infrared imaging techniques. Following a complete experimental campaign (which includes more than 330 steady-state points and fully characterizes the ORC off-design behaviour), a dual data reconciliation method is applied to the raw measurements to obtain a reference dataset. The results are then analysed to assess the charge distribution mechanisms occurring in the ORC and how it is correlated with the system performance. Among other aspects, this paper demonstrates (i) how the charge inventory is highly correlated to the temperature profiles in the heat exchangers, (ii) how the evaporator dictates the operating conditions of the low-pressure components, and (iii) how the system charge and the liquid receiver size can be selected to maximize the ORC overall performance.