Volume 8 Issue 2 ( June 2021 )

Pages_428-437

Temperature and Velocity Changes Across Tube Banks in One-directional and Bi-directional Flow Conditions

Nurjannah Hasbullah, Fatimah Al Zahrah Mohd Saat, Fadhilah Shikh Anuar, Dahlia Johari, Mohamad Firdaus Sukri

[ABSTRACT]

The back-and-forth movement of flow in oscillatory flow condition that can be found in blood flow, thermoacoustic energy system and ocean wave can be categorized as bi-directional flow condition and heat transfer in this flow condition is not well understood. This paper reports an experimental investigation that compares temperature and velocity values between the one-directional (the usual flow condition) and the bi-directional flow conditions. The experiment was done using thermoacoustic’s standing wave rig with two different drivers to drive the one-directional flow and bi-directional flow conditions in the test rig. Results, that were recorded using piezoresistive pressure sensor, type-K thermocouple and hotwire anemometer, indicate that care should be exercised when calculating heat transfer in bi-directional flow conditions as the temperature and velocity changes are different compared to the one-directional flow condition. Differences were recorded to be within the range of 77% for temperature and 59.5% for velocity, presumably due to the different behavior of forced and natural convection effect as flow conditions changed.

Keywords: tube banks, oscillatory flow, heat transfer, thermoacoustic technology.