Related Experiment Video
Updated: Jan 2, 2026

Measurements of Local Instantaneous Convective Heat Transfer in a Pipe - Single and Two-phase Flow
Published on: April 30, 2018
Input impedance measurement of a narrow pipe with thermal gradient
Ashkan Zaker1, Vincent Gibiat1, Stephane Guilain2
1Institut Clément Ader, Université de Toulouse-Paul Sabatier, 3 Rue Caroline Aigle, 31400 Toulouse, France.
Abstract:
Input impedance measurement is commonly used in the design of internal combustion engines to improve their performance. The water-cooled charge-air cooler used in supercharged engines imposes a strong longitudinal thermal gradient on the air contained in its narrow channels. To isolate the resonances caused by the thermal gradient, the input impedance of a semi-infinite narrow pipe with multiple longitudinal temperature profiles is studied experimentally using the Two-Measurement Three-Calibration method. Three known non-resonant loads are used to calibrate the test bench. The importance of using a semi-infinite pipe as a calibration load in narrow pipes is further demonstrated. In the case of this paper, the acoustic propagation is highly influenced by the presence of microphones. The calibration process helps to take into account this influence. Measurements show that the presence of a non-uniform longitudinal temperature profile in the air inside a pipe modifies its input impedance.
Related Concept Videos
Pipe Flowrate Measurement
The orifice meter is a simple,...
Pipe Flowrate Measurement: Problem Solving
Single Pipe Systems
In a Type I problem, fluid properties (density and viscosity), pipe characteristics (including diameter, length, and surface roughness), and the flow rate or average velocity are...
Bernoulli's Equation: Problem Solving
The first step is to compute the cross-sectional areas of the pipe and the Venturi throat to analyze the pressure difference indicated by the pressure gauge. Next, the continuity equation is...
General Characteristics of Pipe Flow I
The classification of fluid...
Laminar Flow: Problem Solving

