Thermal-Hydraulic and Entropy Generation Optimization of Capsule-Type Plate Heat Exchangers With Spherical Dimples

Abstract

The capsule-type plate heat exchanger (PHE) is a new type of equipment with great potential, which is characterized by the concave and convex capsule-like surface. In this article, new structures consisting of capsules and spherical dimples of PHE were proposed. Flow through a periodic unit cell with four different geometries is simulated numerically to characterize the pressure drop, heat transfer coefficients, and entropy generation rate. The numerical results show good consistency with the existing experimental data. Results show that the flow in capsule-type plate can be divided into recirculation zone and high-velocity zone. The staggered capsule structure and the spherical dimple shape generate more secondary and impinging flows, which provide higher Nusselt number and friction factor. The maximum Nusselt number area changed from the upwind region of capsule to the vicinity of dimple region because of the downwash effect and the fluid impact effect. The Nusselt number is enhanced by 19%–46%, and the friction factor is 1.21–2.9 times to that of the primary capsule-type plate. In addition, Entropy analysis illustrates that the maximum reduction in the dimensionless entropy generation rate is 43.6%.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The authors gratefully acknowledge the support provided by the Key research and development plan, National Natural Science Foundation of China (51905545, 51575531), Qingdao Postdoctoral Applied Research Project (qd20180070), the Young Scholar of the Yangtze River Scholars Program (Q2017137), the Taishan Scholar Foundation (ts201511018), and the Fundamental Research Funds for the Central Universities (17CX05019).

Notes on contributors

Zhuwen Shao

Zhuwen Shao is a PhD student at China University of Petroleum (East China), and his main research direction is materials Science and electrochemistry.

Dahai Zhang

Dahai Zhang is an associate professor in the College of New energy, China University of Petroleum (East China). He received his PhD degree in Power Engineering and Engineering Thermophysics from Xi’an Jiaotong University. His research is mainly focused on fluid flow and heat transfer which includes cooling of gas turbine blade, vortex induced vibration power generation, adsorption storage of gas and the engineering application of computational fluid dynamics technique.

Yingzheng Meng

Yingzheng Meng has a master’s degree from China University of Petroleum (East China) and his main research direction is flow induced vibration.

Yu Wan

Yu Wan is a lecturer in the College of New energy, China University of Petroleum (East China). She received her Ph.D. degree in Power Engineering and Engineering Thermophysics from China University of Petroleum (East China). Her research is mainly focused on calculation, testing and control of welding residual stress.

Wenchun Jiang

Wenchun Jiang is a Professor in the College of New energy, China University of Petroleum (East China). He received his Ph.D. degree in Power Engineering and Engineering Thermophysics from Nanjing University of Technology. He was selected as a Chang Jiang young Scholars by the Chinese Ministry of Education, and also selected as the distinguished Expert of Taishan Scholars and Outstanding Youth of Shandong Province. He won the first prize of Science and Technology Progress Award of China Petroleum and Chemical Industry Federation in 2019. His research interests include structural integrity, advanced connection technology, new energy equipment technology, neutron diffraction characterization of material mechanical behavior.