Subrahmanyan Chandrasekhar

“ And it appears not to have been recognized that there exists a special class of shock pulses for which the problem of decay admits of an explicit solution. The case in question arises when shock waves of moderate intensities (i.e., shocks with Mach numbers less than 1.5) are considered. For, under these circumstances (when the ratio of pressures on either side of the shock front is less than 2.5) the increase in entropy of an element of gas as it crosses the shock front can be ignored. ”

“ In equations (3) , θ denotes the temperature which the element of gas under consideration would have when it is reduced to a standard pressure adiabatically. It is evident that θ remains constant during the motion of any element of gas (except when it crosses a discontinuity) . ”

“ It is possible that the laws
are more general than their derivations from equation (31) and (32) would suggest.
Table II
⁠3. On the General Solution of Shock-Pulses with Q = Constant. In §2 we have discussed the special case of linear shock pulses which are characterized by Q = Constant throughout. In this section we shall briefly indicate how the most general shock pulses under the circumstances Q = constant can be constructed. For this purpose we require the general integral of equation (16) . ”