Characterization of the Heat Transfer Process in a Concentric Tube Heat Exchanger for 2-MW Gas Engine Waste Heat Recovery

Abstract Thermoelectric-based waste heat recovery is a competent technique to reduce the exhaust emissions and fuel consumption of automobiles. Thermal and hydraulic characteristics of the exhaust heat exchanger plays a decisive role in the extent of waste heat recovery from the exhaust gas. In this study, the exhaust heat exchanger having twisted tape inserts is proposed to increase the internal heat transfer coefficient. The dimensionless Nusselt number and friction factor were evaluated experimentally for different designs of the twisted tapes. The experiments were performed for the Reynolds number in the range 2300–25000. The considered geometric parameters of the twisted rib explored were the pitch fraction, twist fraction, and slope. The obtained results were compared to reveal the best feasible design of the twisted tape. The maximum net thermohydraulic efficiency factor achieved for the system in the present analysis is 1.93. With the use of twisted tapes, the area of the exhaust heat exchanger can be greatly reduced for the same power output as flat geometry. This would help for the integration of the waste heat recovery with the engine, where the space available is very limited.

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Experimental Investigation on Thermal Performance of Double-U-tube Heat Exchanger Using CuO/water Nanofluid as Heat Transfer Fluid

E3S Web of Conferences ◽

10.1051/e3sconf/202016501022 ◽

2020 ◽

Vol 165 ◽

pp. 01022

Author(s):

Ruiqing Du ◽

Dandan Jiang ◽

Yong Wang

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Thermal Performance ◽

Transfer Process ◽

Heat Transfer Process ◽

Heat Transfer Fluid ◽

Geothermal Heat ◽

Tube Heat Exchanger ◽

Heating And Cooling ◽

Geothermal Heat Exchanger

By applying the shallow ground energy to supply building heating and cooling, the geothermal heat exchanger systems were considered as an energy-efficient building service system. In this study, the CuO/water nanofluid was employed as circuit fluids of the geothermal heat exchanger system, and the thermal performance of the heat exchanger was investigated. The results showed that the heat transfer process of CuO/water nanofluid became stable earlier than that water. Furthermore, the heat transfer rate of nanofluid was higher than that of water when the heat transfer process plateaued.

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Heat Transfer Characteristics of Calcined Petroleum Coke in Waste Heat Recovery Process

Mathematical Problems in Engineering ◽

10.1155/2016/2649383 ◽

2016 ◽

Vol 2016 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Bin Zheng ◽

Yongqi Liu ◽

Lichen Zou ◽

Ruiyang Li

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Petroleum Coke ◽

Heat Recovery ◽

Waste Heat Recovery ◽

Waste Heat ◽

Recovery Process ◽

Heat Transfer Characteristics ◽

Transfer Characteristics ◽

Calcined Petroleum Coke

This paper reports the results of heat transfer characteristics of calcined petroleum coke in waste heat recovery process. The model of heat exchanger was set up. The model has been used to investigate the effects of porosity (0.58 to 0.79), equivalent heat conductivity coefficient (0.9 to 1.1), and equivalent specific heat (0.9 to 1.1). The calculated values of calcined petroleum coke temperature showed good agreement with the corresponding available experimental data. The temperature distribution of calcined petroleum coke, the calcined petroleum coke temperature at heat exchanger outlet, the average heat transfer coefficient, and the heat recovery efficiency were studied. It can also be used in deriving much needed data for heat exchanger designs when employed in industry.

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Analytical solutions of heat and mass transfer process in combined gas-water heat exchanger applied for waste heat recovery

Energy ◽

10.1016/j.energy.2020.118095 ◽

2020 ◽

Vol 206 ◽

pp. 118095

Author(s):

Yiyu Men ◽

Xiaohua Liu ◽

Tao Zhang

Keyword(s):

Mass Transfer ◽

Heat Exchanger ◽

Heat And Mass Transfer ◽

Transfer Process ◽

Analytical Solutions ◽

Heat Recovery ◽

Waste Heat Recovery ◽

Waste Heat ◽

Mass Transfer Process

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Parametric study on heat transfer characteristics of waste heat recovery heat exchanger for automotive exhaust thermoelectric generator

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i2.33.13837 ◽

2018 ◽

Vol 7 (3.3) ◽

pp. 6

Author(s):

Ki. Hyun Kim ◽

Mahesh Suresh Patil ◽

Jae Hyeong Seo ◽

Chan Jung Kim ◽

Gee Soo Lee ◽

...

Keyword(s):

Heat Transfer ◽

Heat Flux ◽

Heat Exchanger ◽

Numerical Analysis ◽

Pressure Drop ◽

Heat Recovery ◽

Waste Heat Recovery ◽

Waste Heat ◽

Heat Transfer Characteristics ◽

Transfer Characteristics

Background/Objectives: The parametric study on heat transfer characteristics of waste heat recovery heat exchanger was carried out by varying different geometry parameters to suggest optimum model for automotive exhaust thermoelectric generator.Methods/Statistical analysis: The numerical analysis method was applied to compare the heat transfer characteristics of various heat exchanger models. For numerical analysis, various models were created using computer aided drawing considering different fin arrangements and guide plates. Commercial code ANSYS 17.0 was used to analyze the heat transfer and fluid flow behavior of various models. Mesh independency was conducted to enhance the accuracy of the results.Findings: The thermal performance analysis of waste heat recovery heat exchanger was conducted considering pressure drop and heat flux at cooling side. As the fin spaces were increased, the heat flux at cooling side increased, but pressure drop also increased.Improvements/Applications: The developed geometry can be further optimized considering other geometry parameters and efficient system could be developed for power generation using waste heat with heat recovery exchanger and the present study provides detailed numerical analysis considering pressure drop and heat flux.

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