12.2.2.7: Maximum Value of Oblique shock

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The maximum values are summarized in the following Table .

\(M_x\)	1.1000	1.2000	1.3000	1.4000	1.5000	1.6000	1.7000	1.8000	1.9000	2.0000	2.2000	2.4000	2.6000	2.8000	3.0000	3.2000	3.4000	3.6000	3.8000	4.0000	5.0000	6.0000	7.0000	8.0000	9.0000	10.0000
\(M_y\)	0.97131	0.95049	0.93629	0.92683	0.92165	0.91941	0.91871	0.91997	0.92224	0.92478	0.93083	0.93747	0.94387	0.94925	0.95435	0.95897	0.96335	0.96630	0.96942	0.97214	0.98183	0.98714	0.99047	0.99337	0.99440	0.99559
\(\delta_{max}\)	1.5152	3.9442	6.6621	9.4272	12.1127	14.6515	17.0119	19.1833	21.1675	22.9735	26.1028	28.6814	30.8137	32.5875	34.0734	35.3275	36.3934	37.3059	38.0922	38.7739	41.1177	42.4398	43.2546	43.7908	44.1619	44.4290
\(\theta_{max}\)	76.2762	71.9555	69.3645	67.7023	66.5676	65.7972	65.3066	64.9668	64.7532	64.6465	64.6074	64.6934	64.8443	65.0399	65.2309	65.4144	65.5787	65.7593	65.9087	66.0464	66.5671	66.9020	67.1196	67.2503	67.3673	67.4419

It must be noted that the calculations are for the perfect gas model. In some cases, this assumption might not be sufficient and different analysis is needed. Henderson and Menikoff suggested a procedure to calculate the maximum deflection angle for arbitrary equation of state. When the mathematical quantity \(D\) becomes positive, for large deflection angle, there isn't a physical solution to an oblique shock. Since the flow "sees'' the obstacle, the only possible reaction is by a normal shock which occurs at some distance from the body. This shock is referred to as the detach shock. The detached shock's distance from the body is a complex analysis and should be left to graduate class and researchers in this area.

Contributors and Attributions

Dr. Genick Bar-Meir. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or later or Potto license.