Potential flow in engine valves Page: 10 of 29
This report is part of the collection entitled: National Advisory Committee for Aeronautics Collection and was provided to Digital Library by the UNT Libraries Government Documents Department.
The following text was automatically extracted from the image on this page using optical character recognition software:
N. A.C.A. Technical Memorandum N o. 343
dependence on m. For very small values of K, a is found, by
computing the limiting value for m, to have the value . + 2
This is then manifestly identical with Kirchhoff's case of the
flow from an infinitely long slit.
d) The pressure-loss coefficient = 1 K was also
plotted (Fig. 9). Its curves are very slightly affected by m
and are strongly hyperbolic.
2. Stream free on only one side.- For very small valve-
lifts, as mentioned in the introduction, the experiments showed
a flow, which did not separate at the point E, but was de-
flected 900 (Fig. 10). It was found that, even mathematically,
such a flow exists, which is treated in what follows. The free
surface is assumed to begin at C, whose anzle a' with the x
axis increases to a maximum value a at the point F and then
again in infinity attains the value a' = 0. The question here
is not therefore concerning an entirely free stream, but con-
cerning a stream which is bounded on one side by a fixed wall
and on tre other by a free surface.
The interesting problem now arises as to whether all con-
ditions of flow, which can occur physically in a configuration
like the flat valve have already been exhausted in the fore-
going cases, It is, in fact, possible to carry out an investi-
gation of this kind, which bears principally on the subject of
the log w plane. The hereby mathematically possible cases
are not always physically possible.
Here’s what’s next.
This report can be searched. Note: Results may vary based on the legibility of text within the document.
Citing and Sharing
Basic information for referencing this web page. We also provide extended guidance on usage rights, references, copying or embedding.
Reference the current page of this Report.
Eck, Bruno. Potential flow in engine valves, report, December 1, 1925; (digital.library.unt.edu/ark:/67531/metadc65148/m1/10/: accessed June 28, 2017), University of North Texas Libraries, Digital Library, digital.library.unt.edu; crediting UNT Libraries Government Documents Department.