New Research Demonstrates "Best Practices" for Coil Design with Smaller Diameter Copper Tubes, Says International Copper Association

Step-by-Step Procedure Applies to the Optimization of RTPF Coils with Smaller Tubes

New York, NY (July 9, 2012) —  The International Copper Association today announced new research results that describe the design and optimization of ACR coils made with MicroGroove technology.

MicroGroove technology is based on the use of smaller-diameter copper tubes with enhanced surfaces in the design and manufacture of round tube, plate fin (RTPF) heat exchanger coils. According to research supported by the ICA, the smaller-diameters of the tubes significantly change patterns of air flow outside of the coil and alter the behavior of the refrigerant inside the coil.

"The design principles emerging from the recent research will be of great value to anyone seeking to optimize material usage in air conditioning and refrigeration applications, whether for an evaporator or a condenser," says Nigel Cotton, MicroGroove Team Leader for the International Copper Association. The ICA sponsors a research and development consortium dedicated to the development of more efficient heat exchanger coils. The consortium includes not only copper tube suppliers but also several major research universities as well as many OEMs who are responsible for a major share of the global production in this product category.

The design and optimization of heat exchangers requires the use of computational fluid dynamics (CFD) methods to analyze the airflow around the tubes and fins and also involves computer simulations of refrigerant flow and temperatures inside the tubes. The ICA research has refined several useful design principles as applied to smaller diameter copper tubes. In particular, the knowledge-based evolution method (KBEM) has been developed into a step-by-step procedure that simulates and optimizes every aspect of the heat exchanger design, from tube spacing to fin type to tube circuitry.

Step-by-Step Design

A methodical approach to the design of heat exchangers using smaller diameter copper tubes is summarized by the following steps.

Step 1: Determine the best ratio of transverse tube pitch to longitudinal tube pitch by fin efficiency analysis.

Step 2: Optimize transverse tube pitch and longitudinal tube pitch by analysis of performance and material cost.

Step 3: Optimize fin pattern by comparing performances of fins with different patterns through CFD-based simulations.

Step 4: Test the performance of heat exchanger with smaller diameter tubes.

Step 5: Develop empiric equations for predicting performance of heat exchanger with smaller diameter tubes.

Additional details about the design principles could be found in the research paper "Principle of Designing Fin-and-Tube Heat Exchanger with Smaller Diameter Tubes for Air Conditioner" by Wei Wu, Guoliang Ding, Yongxin Zheng, Yifeng Gao and Ji Song. The paper will be presented by Wei Wu at the Fourteenth International Refrigeration and Air Conditioning Conference at the Purdue Conferences in West Lafayette, Indiana on July 16-19, 2012. 

Visit www.microgroove.net for information about smaller diameter copper tubes and where to obtain them.

About ICA

The International Copper Association, Ltd. (ICA) is the leading organization for promoting the use of copper worldwide. ICA’s mission is to promote the use of copper by communicating the unique attributes that make this sustainable element an essential contributor to the formation of life, to advances in science and technology, and to a higher standard of living worldwide. Visit www.copperinfo.com for more information about ICA.