US 3908936 A
A multiple liquid flow proportioning system for use in reentry vehicles with transpiration cooled nose tips (TCNT). The basic system includes: a first reservoir containing coolant; a second reservoir containing the same type or a different coolant; a piston for forcing the coolant from the first reservoir and a piston for forcing the coolant from the second reservoir with both pistons integrated to form a unified structure movable in unison; and, a gas-operated mechanism to actuate the pistons and control the flow of coolants to the TCNT. The system provides for the simultaneous fluid cooling of the nose tip at high pressure and low flow rate and cooling of the nose-skirt area at low pressure and high flow rate with a single control device (e.g., valve).
Description (OCR text may contain errors)
United States Patent Durran Sept. 30, 1975  Inventor: Donald A. Durran, Manhattan Beach, Calif.
 Assignee: The United States of America as represented by the Secretary of the Air Force, Washington, DC.
22 Filed: on. 22, 1974 211 App]. No.: 516,933
 US. Cl 244/117 A; 62/467; 102/105; 244/163  Int. Cl. B64C H38  Field of Search 244/117 A. 163; 102/105; 416/95; 62/467, 315, DIG. 5
 References Cited UNITED STATES PATENTS 3 785 59l l/l974 Stalmach 244/1 17 A 3,8()8 833 5/1974 Allen et al. 244/117 A X Prinmry E.\'aminerTrygve M. Blix Assistant E.\'mniner-Barry L. Kelmachter Attorney Agent, or Firm.loseph E. Rusz; Arsen Tashjian 5 ABSTRACT A multiple liquid flow proportioning system for use in reentry vehicles with transpiration cooled nose tips (TCNT). The basic system includes: a first reservoir containing coolant; a second reservoir containing the same type or a different coolant; a piston for forcing the coolant from the first reservoir and a piston for forcing the coolant from the second reservoir with both pistons integrated to form a unified structure movable in unison; and, a gas-operated mechanism to actuate the pistons and control the flow of coolants to the TCNT. The system provides for the simultaneous fluid cooling of the nose tip at high pressure and low flow rate and cooling of the nose-skirt area at low pressure and high flow rate with a single control device (e.g., valve).
3 Claims, 1 Drawing Figure l Z I HHHI 17 IV E P .HHH
lll-lllll HINH HHHI M US. Patent Sept. 30,1975
hmm E E MULTIPLE FLUID FLOW PROPORTIONING -SYSTEM BACKGROUND OF THE INVE NTION This invention relates to the thermal protection of a space vehicle reentering the atmosphere, herein after referred to as a or the reentry vehicle;
Reentry vehicles of large ballistic coefficient (i.e., small nose-cone angles) entering the atmosphere at shallow angles are'subjected to long periods of flight at hypersonic velocity. Such trajectories expose thenose area of the reentry vehicle to extreme temperatures that can only be mitigated by the injection of a coolant over or through the surface to effect transpiration cooling. For a conical shaped nose tip, theflow require ments at the stagnation point, i.e., the tip arequite different from those for the skirt area just behind the'tip. By the present invention I provide a multiple liquid flow proportioning system whereby the noseregion is serviced by a high pressure coolant flowing at a low rate and the skirt region is serviced by a low pressure coolant flowing at a high rate, all controlled by a single control device. I
SUMMARY OF THE INVENTION DESCRIPTION OF THE DRAWING FIG. 1 is a side elevation view, partially in cross section, partially fragmented, and in schematic form of the preferred embodiment of the system.
DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to FIG. 1, wherein a preferred embodiment of the system is shown, there is included a conical reentry vehicle, generally designated 10, having an outer surface 11, a longitudinal axis A-B, and a fore end and an aft end, as designated by the directional arrows and the legends. The reentry vehicle includes a nose section or region 12 and a skirt or side wall section or region 13 at the fore end of the reentry vehicle 10, with the skirt 13 being immediately aft of the nose 12. The nose 12 is shown in a mode detached from the reentry vehicle 10, in the interest of maintaining simplicity of the drawing.
The cooling system is physically within the reentry vehicle 10. It includes: a first reservoir 21 containing a liquid 21A for cooling the nose 12 of the reentry vehicle 10; means for directing flow of the coolant 21A from the first reservoir 21 to the nose 12, with said means generally designated with the reference numeral 22, and wherein said means 22 further includes, for example, a hollow conduit 22A passing into and through the skirt l3 and having two ends, with one end connected to an outlet in the first reservoir 21 and with the other end connected to the junction of a plurality of hollow conduits, such as 228 and 22C, which are in the nose l2 and which lead to the outer surface thereof 12A; a second reservoir 23, preferably but not necessarily located aft of the first reservoir 21, containing a liquid 23A for cooling the skirt 13 of the reentry vehisystem 1s understood from the foregoing description,
cle-.10; means for directing-flow of the coolant 23A- from thesecond reservoir 23 to the skirt 13, which said means generally designated by the'reference numeral 1 v 24, and wherein said means24 further includes, for example, a hollow ;conduit 24Apassing into the skirt '13 and-having two ends, with one end connected'to an outlet in thesecond reservoir 23 'and withthe other end'or end portion connec ted to a plurality of *hollow-con duits, Such as 243, 24C, 24D and 24B, which 'a'r'em skirt 13 and lead-to the outer? surface thereof 12A;""a first piston 25 with a head 25A having a preselected area and a second piston 26 wjtha head 26A and having a preselected area and also having a rear surface 263, with said pistons 25 an'd26 integrated to form a unified structure, and with said unifiedpistons'tructure' wherein the means 29 further includesfor example, but
is not limited to, a hollow conduit'29A having two ends, with one end connected to an outlet in the'first chamber 27 and with the other end connected to an inlet in the second chamber 28, and a suitable valve 298 interp'osed between the two ends of conduit 29A, and conn'ected-to conduit 29A, to control the flow of the gas 27A from first chamber to second chamber 28l The valve 29B"is responsive to standard control means, whether of the on-b'oard type and/or of theremote type, such as a command'signal from a land -ba sedstation. None of the many available conventional valve control means is shown in FIG. 1, because said means, per se, do not form part of the invention.
Also shown in FIG. 1, by use of arrows, are: the direction of flow of the first coolant 21A; the direction of flow of the second coolant 23A; and, the direction of flow of the gas 27A from the first chamber 27 to the second chamber 28, when the valve 298 is in an open mode.
As a related matter, and with regard to the integrated and unified structure of which pistons 25 and 26 are portions, the first piston 25 is preferably disposed essentially on and perpendicular to the longitudinal axis A-B of reentry vehicle 10, although it need not be; and, 'it 25 is movable within, and defines a portion of, first reservoir 21. Similarly, the second piston 26 is disposed essentially perpendicularly to the longitudinal axis A-B of reentry 10; and, it 26 is movable within, and defines a portion of, second reservoir 23. Further, the first piston 25 and the second piston 26 are movable only in unison.
OPERATION OF THE PREFERRED EMBODIMENT The operation of the preferred embodiment of the coupled with reference to FIG. 1.
Essentially the nose 12 is cooled by first coolant 21A which flows from first reservoir 21, and the skirt 13 is cooled by second coolant 23A which flows from second reservoir 23, when these fluids 21A and 23A are simultaneously forced out of their respective reservoirs 21 and 23 by integrated pistons 25 and 26 which are moving, of necessity, in unison forwardly by the action, caused by the pressure, of gas 27A on the rear surface 268 of piston 26, as it 27A is valved from chamber 27 through conduit 29A and into chamber 28.
Since pistons 25 and 26 are moving in unison, it is readily apparent that the rates of flow of coolants 21A and 23A will be proportional to the areas of the heads 25A and 26A of pistons 25 and 26. Furthermore, the pressure that there is available to coolants 21A and 23A is inversely proportional to the area of heads 25A and 26A.
CONCLUSION It is emphasized that, although there have been described and shown the fundamental and unique features of my invention as applied to a preferred embodiment adapted for a particular use, it is to be understood that various other embodiments, substitutions, additions, omissions, adaptations, and the like, will occur to, and can be made by, those of ordinary skill in the art, without departing from the spirit of this invention.
1. A multiple fluid flow proportioning system for use with a low angle reentry space vehicle of conical configuration, with said reentry vehicle having a longitudinal axis, a fore end, and an aft end, and with said reentry vehicle also having a nose and a skirt at the fore end, comprising:
a. a first cylindrical reservoir having a smaller diameter within said reentry vehicle and containing a fluid coolant for cooling said nose of said reentry vehicle;
b. means for directing the controlled flow of said fluid coolant from said first reservoir to said nose of said reentry vehicle;
c. a second cylindrical reservoir having a larger diameter within said reentry vehicle and containing a fluid coolant for cooling said skirt of said reentry vehicle, said second reservoir being coaxial with and spaced apart from the said first reservoir;
d. means for directing the controlled flow of said fluid coolant from said second reservoir to said skirt of said reentry vehicle;
e. a first piston movable through the first reservoir to expel coolant therefrom to the nose of the reentry vehicle;
f. a second piston movable through the second reservoir to expel coolant therefrom to the skirt of the reentry vehicle;
g. means rigidly interconnecting the first and second pistons for movement in unison;
h. a source of pressurized gas; and,
i. controlled means admitting gas from said source to one side of the second piston to move said second piston through the second reservoir whereby coolant is simultaneously expelled at a low flow rate and at a high flow rate respectively from the first and second reservoirs.
2. A system as defined in claim 1 wherein,
the first piston is an elongated stem-like member attached to the second piston and cooperates with the first cylindrical reservoir to stabilize the second piston in moving through the second reservoir.
3. A system as defined in claim 1 wherein,
the source of pressurized gas is a liquified gas expanding into gaseous form in passing through the controlled means admitting gas to one side of the second piston.