Trnsys Model of the Combi Boiler Domestic Hot Water Circuit with a Focus on the Parameter Definition of the Plate Heat Exchanger

Trnsys Model of the Combi Boiler Domestic Hot Water Circuit With a Focus on the Parameter Definition of the Plate Heat Exchanger

“…In this study, the TRNSYS model as shown in In the previously established TRNSYS model (Gök et al, 2022 andGök et al, 2023), the multiplication of the overall heat transfer coefficient and the heat transfer area (symbolized by the UA designation) of the PHE as well is the output provided by the Type 62 -Calling External Programs: Excel™ module. The required measurements in order to define the time-dependent power modulation, UA input, and the HC load profile are explained thoroughly in the Experimental Test Rig section.…”

“…In Figure 6, there are two UA input variation lines for the 8,7 l/min DHW flow rate as the eco and comfort modes. Eco mode variations of the UA input are derived directly from the experimental data as used in the previous TRNSYS model (Gök et al, 2022 andGök et al, 2023). However, the UA input variation for the comfort mode is estimated under constant UA approach which is described in the subsequent regarding section.…”

“…As of the previous studies concerned with the combi boilers, there are many other researches in addition to previously given studies (Atmaca et al, 2015;Atmaca et al, 2016;Gök et al, 2022;and Gök et al, 2023). Ucar and Arslan (2021) stated that the combustion unit including the main heat exchanger had the highest contribution to the total exergy destruction with reference to the advanced exergy analysis for the space heating function of 24 kW commercial condensed combi boiler.…”

“…implementation of the heat retention effects of the HC. Lastly, DHW heating circuit was modelled using the Transient System Simulation Tool (TRNSYS 18) (Klein et al, 2017) and the model achieved a good agreement with the experimental data for both the steady-state and transient temperature profiles of the economic (eco) mode simulations at various operation conditions (Gök et al, 2022). Subsequently, both experimental and numerical validations were displayed elaborately for the CH inlet and outlet temperatures from the HC and the DHW inlet and outlet temperature difference from the PHE at 5 l/min, 7 l/min, and 8,7 l/min DHW user demands in economic mode simulations (Gök et al, 2023).…”

“…The TRNSYS model needs experimental data for the UA parameter definition of the plate heat exchanger and the heat retention effect of the HC block. In the firstly established TRNSYS models (Gök et al, 2022 andGök et al, 2023), UA profile of the PHE was inserted into the model with respect to the transient behavior of the appliance. When compared to the previous 1D DHW circuit model, the temperature profiles of the CH water and DHW were estimated with less mean absolute errors (MAE), mean square errors (MSE), and root mean square errors (RMSE) for the overall time duration including the transient and steadystate regions.…”