AimThis study aimed to identify symptom clusters among patients with chronic heart failure (HF) and examine their independent relationships with quality of life (QoL).MethodsA descriptive cross‐sectional design was adopted, and 201 Chinese participants were recruited. Their symptom profiles and QoL were assessed using the Memorial Symptom Assessment Scale‐Heart Failure and Minnesota Living with Heart Failure Questionnaire. Exploratory factor analysis was used to identify the symptom clusters. Pearson's correlation analysis and multiple regression analysis were conducted to examine their independent relationships with QoL.ResultsSix distinct symptom clusters were identified: the fatigue, dyspneic, discomfort, congestive, ischemic, and emotional symptom clusters. These six symptom clusters accounted for 57.508% of the variance in patient symptom experiences and were positively related to their overall QoL. Moreover, the fatigue (β = .317, p < .001), dyspneic (β = .228, p < .001), congestive (β = .363, p < .001), and emotional (β = .200, p < .001) symptom clusters independently predicted QoL.ConclusionThe six symptom clusters that were identified in this study and the relationships that they shared with QoL are expected to inform future approaches to symptom management. Interventions that target these symptom clusters will improve the QoL of patients with HF.

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Exhaust Gas Recirculation (EGR) is an effective way to reduce nitrogen oxide (NO x) emissions, and the EGR application increases the engine backpressure to some extent. In this paper, a new EGR method named gas-entraining diffuser EGR was proposed to reduce pumping loss. It introduces the exhaust gas into the compressor diffuser inlet where the static pressure is the lowest without blades fouled by exhaust gas. As a result, lower pressure at the turbine upstream can achieve EGR. Then, a newly designed induced structure not only introduces exhaust gas into the compressor diffuser but also reduces the energy loss caused by EGR application. Furthermore, the performance of compressor with different induced angles of the induced structure was investigated using simulation method. Results showed that the compressor’s adiabatic efficiency was the best when the induced angle was 20°. Regarding the induced angle of 20°, the adiabatic efficiency drop of compressor was in the range of 0.8%–12%. Approximately 10% of the adiabatic efficiency drop was caused by the induced structure, the other was mainly from the flow loss and mixing loss in diffuser system. The induced structure mainly affected the static pressure difference between induced structure inlet and impeller outlet ([Formula: see text]). When the impeller mass flow was 0.23 kg/s, [Formula: see text] was 11.21, 13.95, 15.59, 17.18 kPa respectively with corresponding induced angles of 20°, 30°, 40°, 50°. The primary energy loss leading to the adiabatic efficiency drop of compressor with induced structure occurred in diffuser system. It was caused by the mixing process of induced gas and impeller exit gas, and the enhanced effect from the shroud side’s impeller jet-wake and volute tongue.