Heat Transfer Engineering to publish a scientific article from one of Koja’s engineers


Research on heat transfer technology is a significant part of product development at Koja. Turo Välikangas, our Research & Development Engineer, studies in the Doctoral School of Industry Innovations at Tampere University of Technology. In his article, Välikangas examines conjugate heat transfer in a fin-and-tube heat exchanger simulation. He presented his article at the ICCHMT conference in Kraków in May 2016. Based on his presentation, his article was chosen for publication in a special issue of Heat Transfer Engineering. The issue will come out in February or March 2018.

In his study, Välikangas focused on studying the importance of conjugate heat transfer in the Computational Fluid Dynamics simulation of a fin-and-tube heat exchanger. 

“Up until now, the convection on the air side of the heat exchanger has been resolved by using constant temperature on the surface of the fin as a boundary condition, after which the fin efficiency has been included in the calculations. This calculation method does not reflect the quality of the geometrical changes in the heat exchanger, as the fin efficiency is independent of the shape of the fin. However, conjugate heat transfer can be used to examine the quality of the geometrical changes taking place during the simulation,” Välikangas explains. Click here to read more about the article »

The knowledge gained in this research project will be used in the development of Koja’s product in the future.

Turo Välikangas at Koja's product development and test centre. The centre will be completed by the end of 2017.

Välikangas to speak at the OpenFOAM® workshop

During spring semester this year, Välikangas did a research visit at the Energy Technology Department in Aalborg University and his next scientific article will be based on his work in Aalborg. The new article is a geometrical improvement study based on a combined herringbone fin shape and vortex generator design.

“We sought to improve the commonly used herringbone fin shape analysed by the group in a way that would simultaneously reduce the pressure drop and increase heat transfer,” says Välikangas.

Välikangas has been invited to speak at the OpenFOAM® software conference, which will be held at the University of Exeter in Great Britain on 24–27 July 2017. His lecture will focus on the mesh generation for complex conjugate heat transfer problems. As an example, Välikangas uses the fin-and-tube heat exchanger to demonstrate how the meshing of the studied medium can be done with Open Source Software.

Koja’s product development and test centre to open soon

Koja’s product development and test centre will be completed by the end of 2017. The centre will make it possible to test and measure Koja’s own products and solutions and to carry out measurements for customer projects.

“Next winter, I intend to carry out measurements related to Koja’s own products and alternatives found around the world in the new measurement laboratory. My goal is to use the data for model validation in the final articles of my dissertation,” says Välikangas.

At the centre, the environmental chambers and a measuring arrangement for larger air-handling machines will enable tests to be performed in a variety of conditions. This will make it possible to test the air handling units, data centres or cabin automation in a real working environment.

Read more »

And that’s not all...

The Tampere Region branch of the “Federation of Finnish Technology Industries” has awarded a grant to Välikangas for his Master’s thesis. In his thesis, Välikangas studied the development of a fin-and-tube heat exchanger simulation method using open source software. His work was considered to support the general development of the technology industries.

Read more about the Master’s thesis of Välikangas »