Apparatus for characterizing the temporo-spatial properties of a dynamic fluid front and method thereof

• US 8,620,614 B2
• Filed: 11/30/2007
• Issued: 12/31/2013
• Est. Priority Date: 01/03/2006
• Status: Expired due to Fees

• Current Assignee: UT-Battelle LLC
• Original Assignee: UT-Battelle LLC
• Inventors: Battiste, Richard L.
• Primary Examiner(s): Nghiem, Michael
• Assistant Examiner(s): Satanovsky, Alexander
• Application Number:
  US11/998,597
• Publication Number:
  US 20130313742A1
• Time in Patent Office: 2,223 Days
• Field of Search: 702/130, 264/40.1, 264/40.6, 264/40.7
• US Class Current: 702/130
• CPC Class Codes: B29C 35/007 Tempering units for temperature control of moulds or cores, e.g. comprising heat exchangers, controlled valves, temperature-controlled circuits for fluids B29C35/0294 takes precedence
• CPC Class Codes: B29C 45/0046 Details relating to the filling pattern or flow paths or flow characteristics of moulding material in the mould cavity
• CPC Class Codes: B29C 45/14631 Coating reinforcements fibre reinforcements B29C45/0005
• CPC Class Codes: B29C 70/48 and impregnating the reinforcements in the closed mould, e.g. resin transfer moulding [RTM] , e.g. by vacuum
• CPC Class Codes: B29C 70/546 Measures for feeding or distributing the matrix material in the reinforcing structure
• CPC Class Codes: G01K 1/026 arrangements for monitoring a plurality of temperatures, e.g. by multiplexing
• CPC Class Codes: G01K 3/08 giving differences of values using thermoelectric elements G01K7/02; giving differentiated values
• CPC Class Codes: G01K 3/10 in respect of time, e.g. reacting only to a quick change of temperature

Abstract

Methods and apparatus are described for characterizing the temporal-spatial properties of a dynamic fluid front within a mold space while the mold space is being filled with fluid. A method includes providing a mold defining a mold space and having one or more openings into the mold space; heating a plurality of temperature sensors that extend into the mold space; injecting a fluid into the mold space through the openings, the fluid experiencing a dynamic fluid front while filling the mold space with the fluid; and characterizing temporal-spatial properties of the dynamic fluid front by monitoring a temperature of each of the plurality of heated temperature sensors while the mold space is being filled with the fluid. An apparatus includes a mold defining a mold space; one or more openings for introducing a fluid into the mold space and filling the mold space with the fluid, the fluid experiencing a dynamic fluid front while filling the mold space; a plurality of heated temperature sensors extending into the mold space; and a computer coupled to the plurality of heated temperature sensors for characterizing the temporal-spatial properties of the dynamic fluid front.

Claims

1. An apparatus, comprising:

a mold defining a mold space, the mold space being configured to receive and contain a fluid that solidifies to the shape of the mold space;

one or more openings for introducing the fluid into the mold space and filling the mold space with the fluid, the fluid experiencing a dynamic fluid front while filling the mold space;

a plurality of holes extending through the mold, each of the plurality of holes forming side surfaces of the mold that extend from an outer surface of the mold to an inner surface of the mold;

a plurality of heated temperature sensors extending through the holes and into the mold space, the plurality of heated temperature sensors being arranged in a uniform distribution throughout the mold for characterization of temporal-spatial properties of the dynamic fluid front in the mold space, wherein the plurality of sensors are further arranged symmetrically around each of the one or more openings to allow characterization of the temporal-spatial properties of the dynamic fluid front of the fluid in all directions away from each of the one or more openings; and

a computer coupled to the plurality of heated temperature sensors, the computer configured to characterize the temporal-spatial properties of the dynamic fluid front based on data received from the plurality of heated temperature sensors arranged in the uniform distribution throughout the mold,

wherein each of the plurality of heated temperature sensors is bonded to the mold at the outside surface of the mold, and

wherein each of the holes comprises a space in between the plurality of heated temperature sensors and the side surfaces, the space extending from the inner surface to the outside surface where the heated temperature sensor is bonded.

2. The apparatus of claim 1, wherein each of the plurality of heated temperature sensors includes:

a thermocouple;

a heater wire running parallel to the thermocouple, and electrically isolated from the thermocouple;

an electrically insulating structural adhesive encasing both the thermocouple and the heater wire; and

an electrical and thermal insulator tube encasing the electrically insulating structural adhesive,

wherein the thermal conductivity of the structural adhesive is higher than the thermal conductivity of the thermal insulator tube.

3. The apparatus of claim 2, wherein the space between the mold and the thermal insulator tube is sufficiently narrow to prevent the fluid inside the mold space from entering the space between the mold and the thermal insulator tube.

4. The apparatus of claim 1, further comprising a robotic arm for placing preforms within the mold space.

5. The apparatus of claim 1, further comprising a constricting valve coupled to each of the one or more openings for controlling a conductance of each of the one or more openings.

6. The apparatus of claim 1, wherein each of the heated temperatures sensors is bonded at the outside surface at a distance sufficiently far away from a tip of the heated temperature sensor inside the mold space to prevent significant transfer of heat from the tip to the mold.

7. The apparatus of claim 1, wherein the computer is further configured to:

record, as heat loss data, an amount of heat lost as a function of time from the data received from the plurality of heated temperature sensors arranged in the uniform distribution throughout the mold; and

convert the heat loss data into data indicating a spatial position of the dynamic fluid front within the mold space as a function of time.

8. The apparatus of claim 1, wherein the computer is configured to characterize the temporal-spatial properties of the dynamic fluid front at all locations within the mold space based on the uniform distribution of the plurality of temperature sensors throughout the mold.

9. A method, comprising:

providing a mold defining a mold space and having one or more openings into the mold space;

heating a plurality of temperature sensors that extend into the mold space, the plurality of heated temperature sensors being arranged in a uniform distribution throughout the mold for characterization of a spatial position as a function of time of a dynamic fluid front of fluid in the mold space, wherein the plurality of sensors are further arranged symmetrically around each of the one or more openings to allow characterization of the temporal-spatial properties of the dynamic fluid front of the fluid in all directions away from each of the one or more openings;

injecting the fluid into the mold space through the openings, the fluid experiencing a dynamic fluid front while filling the mold space with the fluid; and

characterizing the spatial position of the dynamic fluid front as a function of time by monitoring temperature data received from each of the plurality of heated temperature sensors arranged in the uniform distribution throughout the mold while the mold space is being filled with the fluid,

wherein characterizing the temporal-spatial properties comprises;

setting the temperature of each of the plurality of heated temperature sensors based on an anticipated temperature of the fluid in the mold space.

10. The method of claim 9, further comprising placing a preform within the mold space prior to filling the mold space with the fluid.

11. The method of claim 10, wherein the preform includes an electrically conductive material.

12. The method of claim 10, wherein each of the plurality of heated temperature sensors includes a wireless transceiver and monitoring of each of the plurality of heated temperature sensors is achieved using the a wireless transceiver.

13. The method of claim 9, wherein characterizing further comprises:

recording, as heat loss data, an amount of heat lost as a function of time from each of the plurality of heated temperature sensors by monitoring the temperature of each of the plurality of heated temperature sensors while the mold space is being filled with the fluid; and

converting the heat loss data into data indicating a the spatial position of the dynamic fluid front within the mold space as a function of time.

14. The method of claim 9, wherein setting the temperature of each of the plurality of heated temperature sensors comprises setting the temperature of each of the plurality of heated temperature sensors to a temperature greater than an anticipated temperature of the fluid in the mold space.

15. The method of claim 9, further comprising transforming data of the spatial position of the dynamic fluid front as a function of time to control a flow of the fluid through each of the one or more openings into the mold space while the mold space is being filled with the fluid.

16. The method of claim 15, wherein transforming includes:

comparing the position of the dynamic fluid front within the mold space in real time with a pre-established desired fluid front profile as a function of time while the mold space is being filled with the fluid;

determining whether a flow of fluid into the mold space through each of the one or more openings needs to be increased or decreased based on the pre-established desired fluid front profile;

transmitting a control signal to constricting valves coupled to each of the one or more openings to increase or decrease the flow of fluid.

17. The method of claim 16, further comprising repeating comparing, determining and transmitting while the mold space is being filled with the fluid.