Calorimeter apparatus accurately measures very small temperature rises on a test surface subjected to aerodynamic heating. A continuous thin sheet of a sensing material is attached to a base support plate through which a series of holes of known diameter have been drilled for attaching thermocouples to the material

Harvey, W. D.

Miller, H. B.

English

NASA Technical Reports Server

December 1966	 Brief 66-10637 
NASA TECH BRIEF
%W 
NASA Tech Briefs are issued to summarize specific innovations derived from the U.S. space program, 
to encourage their commercial application. Copies are available to the public at 15 cents each 
from the Clearinghouse for Federal Scientific and Technical Information, Springfield, Virginia 22151. 
Instrument Accurately Measures Small Temperature Changes on Test Surface 
Bonding Material (Insulator) 
(uirometf/IUmeuI 
The problem: 
To devise an accurate method of measuring very 
small temperature rises (on the order of 1 0 to 2°C) 
occurring over time intervals of approximately 0.1 
second on a test surface subjected to aerodynamic 
heating. 
The solution: 
The method involves the attachment of a con-
tinuous thin sheet of a sensing material to a base sup-
port plate (model body) through which a series of 
holes of known diameter have been drilled.- When 
thermocouples are attached to the sensing material 
through the drilled holes, each disk of sensing material 
serves as an individual calorimeter.
How it's done: 
The steel support plate, machined and ground 
smooth on one face, is drilled with 0.25-inch diameter 
holes at specified locations to accommodate the ther-
mocouples. A 0.001-inch thick bonding material simi-
lar to double-backed tape is used under controlled 
temperature and pressure to attach the 0.002-inch 
thick 302 stainless-steel sensing skin to the support 
plate. This construction provides a smooth, uniform 
thin-skin surface, which serves as a calorimeter-type 
heat-transfer gage at each of the 0.25-inch hole loca-
tions. Chromel/alumel thermocouple wires (0.001- 
inch diameter) are then resistance welded onto the 
back side of the thin skin as near the center of the 
disks as possible. Copper lead wires of much larger 
(continucd overleaf) 
This document was prepared under the sponsorship of the National 	 Government assumes any liability resulting from the use of the 
Aeronautics and Space Administration. Neither the United States 	 information contained in this document, or warrants that such use 
Government nor any person acting on behalf of the United States 	 will be free from privately owned rights.
https://ntrs.nasa.gov/search.jsp?R=19660000635 2020-03-11T17:45:52+00:00Z
diameter are joined to the 0.00l -inch diameter ther-
mocouple wires. 
Notes: 
1. The output signals from the thermocouples are of 
sufficient amplitude, so that the thermocouple 
lead wires can be directly connected to a sensitive 
galvanometer and oscillograph readout system. 
2. This type of construction should be applicable to 
other geometries such as cylinders, wedges, and 
irregular shapes. 
3. Further information concerning this instrument is 
given in NASA TN D-2846, "Effects of Leading-
Edge Bluntness on Pressure and Heat-Transfer 
Measurements Over a Flat Plate at a Mach Num-
ber of 20", by William D. Harvey, October 1965, 
available from the Clearinghouse for Federal 
Scientific and Technical Information, Springfield, 
Virginia 22151. Inquiries may also be directed to: 
Technology Utilization Officer 
Langley Research Center 
Langley Station 
Hampton, Virginia 23365 
Reference: B66-10637
Patent status: 
This invention is owned by NASA, and a patent 
application has been filed. Royalty-free, nonexclu-
sive licenses for its commercial use will be granted by 
NASA. Inquiries concerning license rights should be 
made to NASA, Code GP, Washington, D.C. 20546. 
Source: William D. Harvey 
and Howard B. Miller 
(Langley-174) 
Brief 66-10637	 Category 01


Instrument accurately measures small temperature changes on test surface

Abstract

Similar works

Full text

Available Versions

NASA Technical Reports Server