• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11b
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• pp.1306-1312
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• 2001

In this study. the acoustic power balancing method to analysis HVAC system noise is presented. The method can consider not only forward but also backward propagations of noise generated by the operation of air supply units and aerodynamical disturbance at duct elements. This can be done by estimating sound transmission and reflection properties of duct elements. and balancing acoustic powers of total HVAC system. To verify the accuracy of the presented method. numerical analysis for a HVAC system is carried out and the results are compared with those obtained by a traditional empirical method. suggested by National Environmental Balancing Bureau.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.554-558
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• 2004

In this paper, we introduce noise prediction program of HVAC system to assist low-noisy design of ship's cabin. The developed program calculates sound power levels at HVAC components considering primary and secondary noise generated by fan and duct element, duct element noise attenuation, and duct break-in noise based on the authentic empirical method suggested by NEBB and acoustic power balancing method. Sound pressure level at cabin with or without ceiling system is evaluated by the diffuse-field theory considering diffuser and duct break-out sound powers. Moreover, the program provides intuitive pre- and post-processors using modem GUI functions to help efficient modeling and evaluation of cabin and HVAC component noise. To validate the accuracy and convenience of the program, noise prediction for a HVAC system is demonstrated.

• Special Issue of the Society of Naval Architects of Korea
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• 2006.09a
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• pp.65-70
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• 2006

In this paper, we introduce prediction program of HVAC system, HJNOVAC Version 2.0. The developed program adopts both the authentic empirical method suggested by NEBB and acoustic power balancing method. The program provides intuitive pre- and post- processor using modern GUI function to help efficient modeling and evaluation of cabin and HVAC component noises. To verify the accuracy and convenience of the program, we carry out noise prediction of HVAC system for 8,100 TEU Container Carrier and measure the noise levels of cabins during sea trial.