Effects of the exhaust gas heat recovery system with a plate heat exchanger on the warm-up performance  characteristics of the gasoline engine

Background/Objectives: To meet the regulations for the fuel economy, an EHRS (Exhaust gas Heat Recovery System, which was installed within the vehicle exhaust system and recovered the heat from the exhaust gas, were needed. The EHRS enabled the engine to achieve the fast warm-up performance for reducing friction loss during the cold start.The objective of this paper was to investigate the effects of the design parameters of the EHRS with a plate heat exchanger on the warm-up performance of a gasoline engine.Methods/Statistical analysis: The EHRS with the plate heat exchanger was manufactured and installed behind the catalyst in the exhaust system of the gasoline direct injection engine. The experimental study and multi-disciplinary analysis were carried out to investigate the effects of the EHRS on the warm-up performance of the engine, such as the coolant temperature, the exhaust gas temperature and the recovery heat at idle condition and the step-load condition.Findings: Because the recovery of heat was about 1. 7 kW at idle condition, the effect of the EHRS on the warm-up performance was negligible. However, due to 17.2 kW of the recovery of heat at the stepload condition of T=140 Nm at N=2,400 rpm, the EHRS enabled to shorten the warm-up time by 548 s comparison that of the base engine.Improvements/Applications: The fuel economy will be expected to be improved through an EHRS, which provides the improved combustion in the warm-up phase and a decrease in friction loss.

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Thermal performance analysis of plate heat exchanger with different configurations for the heat recovery system in buildings

International Journal of Sustainable Energy ◽

10.1080/14786451.2014.905580 ◽

2014 ◽

Vol 35 (4) ◽

pp. 339-359

Author(s):

Mohamed Sakr

Keyword(s):

Heat Exchanger ◽

Performance Analysis ◽

Thermal Performance ◽

Heat Recovery ◽

Plate Heat Exchanger ◽

Plate Heat ◽

Recovery System ◽

Heat Recovery System

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Modeling and Simulation of an Inverted Brayton Cycle as an Exhaust-Gas Heat-Recovery System

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4035738 ◽

2017 ◽

Vol 139 (8) ◽

Cited By ~ 4

Author(s):

Zhihang Chen ◽

Colin Copeland ◽

Bob Ceen ◽

Simon Jones ◽

Alan Agurto Goya

Keyword(s):

Heat Exchanger ◽

Internal Combustion Engine ◽

Thermodynamic Model ◽

Heat Recovery ◽

Test Bench ◽

Combustion Engine ◽

Brayton Cycle ◽

Exhaust Gas ◽

Recovery System ◽

Heat Recovery System

The exhaust gas from an internal combustion engine contains approximately 30% of the thermal energy of combustion. The exhaust-gas heat-recovery systems aim to reclaim a proportion of this energy in a bottoming thermodynamic cycle to raise the overall system thermal efficiency. The inverted Brayton cycle (IBC) considered as a potential exhaust-gas heat-recovery system is a little-studied approach, especially when applied to small automotive power-plants. Hence, a model of the inverted Brayton cycle using finite-time thermodynamics (FTT) is presented to study heat recovery applied to a highly downsizing automotive internal combustion engine. IBC system consists of a turbine, a heat exchanger (HE), and compressors in sequence. The use of IBC turbine is to fully expand the exhaust gas available from the upper cycle. The remaining heat in the exhaust after expansion is rejected by the downstream heat exchanger. Then, the cooled exhaust gases are compressed back up to the ambient pressure by one or more compressors. In this paper, the exhaust conditions available from the engine test bench data were introduced as the inlet conditions of the IBC thermodynamic model to quantify the power recovered by IBC, thereby revealing the benefits of IBC to this particular engine. It should be noted that the test bench data of the baseline engine were collected by the worldwide harmonized light vehicles test procedures (WLTP). WLTP define a global harmonized standard for determining the levels of pollutants and CO2 emissions, fuel consumption. The IBC thermodynamic model was simulated with the following variables: IBC inlet pressure, turbine pressure ratio, heat exchanger effectiveness, turbomachinery efficiencies, and the IBC compression stage. The aim of this paper is to analysis the performance of IBC system when it is applied to a light-duty automotive engine operating in a real-world driving cycle.

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Modelling and Simulation of an Inverted Brayton Cycle as an Exhaust-Gas Heat-Recovery System

ASME 2016 Internal Combustion Engine Fall Technical Conference ◽

10.1115/icef2016-9363 ◽

2016 ◽

Cited By ~ 4

Author(s):

Z. Chen ◽

C. D. Copeland ◽

B. Ceen ◽

S. Jones ◽

A. A. Goya

Keyword(s):

Heat Exchanger ◽

Internal Combustion Engine ◽

Thermodynamic Model ◽

Heat Recovery ◽

Test Bench ◽

Combustion Engine ◽

Brayton Cycle ◽

Exhaust Gas ◽

Recovery System ◽

Heat Recovery System

The exhaust gas from an internal combustion engine contains approximately 30% of the thermal energy of combustion. The exhaust-gas heat-recovery systems aim to reclaim a proportion of this energy in a bottoming thermodynamic cycle to raise the overall system thermal efficiency. The inverted Brayton cycle considered as a potential exhaust-gas heat-recovery system is a little-studied approach, especially when applied to small automotive power-plants. Hence, a model of the inverted Brayton cycle using finite-time thermodynamics (FTT) is presented to study heat recovery applied to a highly downsizing automotive internal combustion engine. IBC system consists of a turbine, a heat exchanger and compressors in sequence. The use of IBC turbine is to fully expand the exhaust gas available from the upper cycle. The remaining heat in the exhaust after expansion is rejected by the downstream heat exchanger. Then, the cooled exhaust gases are compressed back up to the ambient pressure by one or more compressors. In this paper, the exhaust conditions available from the engine test bench data were introduced as the inlet conditions of the IBC thermodynamic model to quantify the power recovered by IBC, thereby revealing the benefits of IBC to this particular engine. It should be noted that the test bench data of the baseline engine were collected by the worldwide harmonized light vehicles test procedures (WLTP). WLTP define a global harmonized standard for determining the levels of pollutants and CO2 emissions, fuel consumption. The IBC thermodynamic model was simulated with the following variables: IBC inlet pressure, turbine pressure ratio, heat exchanger effectiveness, turbomachinery efficiencies, and the IBC compression stage. The aim of this paper is to analysis the performance of IBC system when it is applied to a light-duty automotive engine operating in a real world driving cycle.

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Research on Waste Heat Recovery in Drain Water of Barbershop

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.204-208.4229 ◽

2012 ◽

Vol 204-208 ◽

pp. 4229-4233 ◽

Cited By ~ 1

Author(s):

Fang Tian Sun ◽

Na Wang ◽

Yun Ze Fan ◽

De Ying Li

Keyword(s):

Heat Exchanger ◽

Heat Recovery ◽

Waste Heat Recovery ◽

Waste Heat ◽

Utilization Efficiency ◽

Drain Water ◽

Waste Heat Recovery System ◽

Heat Utilization ◽

Recovery System ◽

Heat Recovery System

Drain water at 35°C was directly discharged into sewer in most of barbershop with Electric water heater. Heat utilization efficiency is lower, and energy grade match between input and output is not appropriate in most of barbershops. Two waste heat recovery systems were presented according to the heat utilization characteristics of barbershops and principle of cascade utilization of energy. One was the waste heat recovery system by water-to-water heat exchanger (WHR-HE), and the other is the waste heat recovery system by water-to-water heat exchanger and high-temperature heat pump (WHR-CHEHP). The two heat recovery systems were analyzed by the first and second Laws of thermodynamic. The analyzed results show that the energy consumption can be reduced about 75% for HR-HE, and about 98% for WHR-CHEHP. Both WHR-HE and WHR-CHEHP are with better energy-saving effect and economic benefits.

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