## THERMAL SCIENCE

International Scientific Journal

### EXPERIMENTAL CALIBRATION OF THE MATHEMATICAL MODEL OF AIR TORQUE POSITION DAMPERS WITH NON-CASCADING BLADES

**ABSTRACT**

This paper is focused on the mathematical model of the Air Torque Position dampers. The mathematical model establishes a link between the velocity of air in front of the damper, position of the damper blade and the moment acting on the blade caused by the air flow. This research aims to experimentally verify the mathematical model for the damper type with non-cascading blades. Four different types of dampers with non-cascading blades were considered: single blade dampers, dampers with two cross-blades, dampers with two parallel blades and dampers with two blades of which one is a fixed blade in the horizontal position. The case of a damper with a straight pipeline positioned in front of and behind the damper was taken in consideration. Calibration and verification of the mathematical model was conducted experimentally. The experiment was conducted on the laboratory facility for testing dampers used for regulation of the air flow rate in heating, ventilation and air conditioning systems. The design and setup of the laboratory facility, as well as construction, adjustment and calibration of the laboratory damper are presented in this paper. The mathematical model was calibrated by using one set of data, while the verification of the mathematical model was conducted by using the second set of data. The mathematical model was successfully validated and it can be used for accurate measurement of the air velocity on dampers with non-cascading blades under different operating conditions. [Projekat Ministarstva nauke Republike Srbije, br. TR31058]

**KEYWORDS**

PAPER SUBMITTED: 2015-01-31

PAPER REVISED: 2015-08-22

PAPER ACCEPTED: 2015-08-22

PUBLISHED ONLINE: 2015-09-06

**THERMAL SCIENCE** YEAR

**2016**, VOLUME

**20**, ISSUE

**Issue 2**, PAGES [567 - 578]

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