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Effect of Unsteady Flow on Intercooler Performance
Technical Paper
2014-01-2220
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
Two compact intercoolers are designed for the Rotax 914 aircraft engine to increase engine power and avoid engine knock. A study is performed to investigate the effects of unsteady airflow on intercooler performance. Both intercoolers use air-to-liquid cross flow heat exchangers with staggered fins. The intercoolers are first tested by connecting the four air outlets of the intercooler to a common restricted exit creating a constant back pressure which allows for steady airflow. The intercoolers are then tested by connecting the four air outlets to a 2.4 liter, 4 cylinder engine head and varying the engine speed from 6000 to 1200 RPM corresponding to decreasing flow steadiness. The test is performed under average flight conditions with air entering the intercooler at 180°F and about 5 psig. Results from the experiment indicate that airflow unsteadiness has a significant effect on the intercooler's performance. Temperature spread across the intercooler's outlets varies from 30°F to 5°F as airflow unsteadiness increases. The Stagnation pressure drop across the intercooler varies from 0.8 psi to 2.7 psi as airflow unsteadiness increases. The effectiveness of the intercooler without internal baffling is independent of the level of flow steadiness with a value of about 0.55. The effectiveness of the intercooler with an internal baffling system has a value of about 0.53 when disconnected from the engine and about 0.58 when connected to the engine. These results indicate that flow unsteadiness has a strong effect on intercooler performance and should be accounted for when designing and testing an intercooler.
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Citation
Miller, J., Hoke, J., and Schauer, F., "Effect of Unsteady Flow on Intercooler Performance," SAE Technical Paper 2014-01-2220, 2014, https://doi.org/10.4271/2014-01-2220.Also In
References
- Azaj , M. , Flaherty , S. , Gintings , E. , Shankar , A. et al. Fuel-Cooled Intercooler for Rotax 914 Engine Purdue University 2012
- Searle , M. , Downer , R. , Christiansen , T. , Sakamaki , J. , Mecham et al. Intercooler for Rotax 914 Engine Brigham Young University Apr. 2013
- Hribernik , A. , Moskwa , J. Transient Response of a Cross-Flow Charge Air Intercooler and Its Influence on Engine Operation J. Dyn. Sys., Meas., Control 122 3 483 489 1998 10.1115/1.1286683
- Bromnick , P. , Pearson , R. , and Winterbone , D. Intercooler Model for Unsteady Flow in Engine Manifolds Journal of Automotive Engineering 212 2 119 132 1998 10.1243/0954407981525849
- Cengel , Y.A. Heat Transfer McGraw-Hill New York 0-07-245893-3 2003
- Mai , T. , Chitou , N. , and Padet , J. Heat Exchanger Effectiveness in Unsteady State The European Physical Journal Applied Physics 8 1 71 75 1999 http://dx.doi.org/10.1051/epjap:1999231