DE102022211412A1 - Method, program and device for cooling simulation and cooling method for a workpiece - Google Patents

Abstract

[Task] To provide a method, a program and an apparatus for cooling simulation, which can shorten the calculation time, and a cooling method for a workpiece. [Solution] The method for cooling simulation is a method for cooling simulation, a temperature change inside a workpiece when the heated workpiece has been contacted with a coolant. In this cooling simulation method, the flow rate of the coolant on the surface of the workpiece is calculated by a history analysis of the coolant using a heat flow simulation, and the temperature change inside the workpiece is calculated based on the temperature of the surface of the workpiece and the calculated flow rate.

Description

[Technical Field]

The embodiment of the present invention relates to a cooling simulation method, program and apparatus, and a cooling method for a workpiece.

[background technology]

When quenching a steel component, after a workpiece has been heated to a temperature greater than or equal to the austenite transformation temperature, the workpiece suddenly cools down as a result of the workpiece surface coming into contact with a coolant. This cooling behavior affects properties such as hardness, strain magnitude, residual stress, etc. of the respective parts of the workpiece after quenching. Since there are numerous factors that influence the cooling behavior, e.g. B. the material and shape of the workpiece, the cooling method, the workpiece installation state in cooling, the type and flow rate of coolant, etc., determining the optimum cooling conditions for quenching by trial and error using a real machine takes a lot of time and causes high costs Costs. Therefore, attempts have recently been made to predict the cooling behavior by means of a heat flow simulation using a numerical analysis method such as the finite volume method or the finite difference method, the particle method, etc.

However, in order to simulate the cooling with sufficient precision in practical use, the boiling phenomenon of the coolant must be taken into account. The boiling phenomenon is complicated and consists of membrane boiling, core boiling, etc., so an accurate simulation of the cooling behavior of the workpiece including the boiling phenomenon of the coolant becomes very complex and takes a lot of calculation time.

[Prior Art Documents]

[patent documents]

[Patent Document 1] Patent Publication No. JP 2010-230331 A

[Outline of the Invention]

[Problem to be solved by the invention]

The embodiment of the present invention aims to provide a cooling simulation method, a program and an apparatus by which the calculation time can be shortened, and a cooling method for a workpiece.

[means for solving the task]

The cooling simulation method according to the embodiments of this invention is a cooling simulation method for predicting a temperature change inside a workpiece when the surface of the heated workpiece is brought into contact with a coolant. In this cooling simulation method, through a flow analysis of the coolant using a heat flow simulation, the flow rate of the coolant on the surface of the workpiece is calculated, and based on the temperature of the surface of the workpiece and the calculated flow rate, the temperature change inside the workpiece is calculated.

The cooling simulation program according to the embodiments of this invention is a cooling simulation program for predicting a temperature change inside a workpiece when the surface of the workpiece is brought into contact with a coolant. In this cooling simulation program, the flow rate of the coolant on the surface of the workpiece is calculated on a computer by heat flow simulation, and the temperature change inside the workpiece based on the temperature of the surface of the workpiece and the calculated flow rate.

The cooling simulation apparatus according to the embodiments of this invention is a cooling simulation apparatus for predicting a temperature change inside a workpiece when the surface of the workpiece is contacted with a coolant. The cooling simulation apparatus includes a calculation section for calculating the flow rate of the coolant on the surface of the workpiece by heat flow simulation and the temperature change inside the workpiece based on the temperature of the surface of the workpiece and the calculated flow rate.

The cooling method for a workpiece according to an embodiment of the present invention includes a step of setting cooling conditions using the cooling simulation method and a step of cooling the workpiece using the cooling conditions set.

[Effects of the Invention]

The embodiment of the present invention aims to provide a cooling simulation method, a program and an apparatus by which the calculation time can be shortened, and a cooling method for a workpiece.

character list

• [ 1 ] 1 (a) 13 is a block diagram showing a cooling simulation apparatus according to a first embodiment, and 1 (b) Fig. 12 is a block diagram showing a computing section
• [ 2 ] 2 (a) and 2 B) 12 are views showing the operation of the cooling simulation apparatus according to the first embodiment, in which (a) shows a simulation of the heating process and (b) shows a simulation of the cooling process.
• [ 3 ] 3 Fig. 12 is a graph in which the lateral axis is the workpiece surface temperature and the longitudinal axis is the heat transfer coefficient at the workpiece surface, and shows the relationship between the workpiece surface temperature, the coolant flow rate and the heat transfer coefficient.
• [ 4 ] 4 14 is a flowchart showing a heating simulation method in the first embodiment.
• [ 5 ] 5 14 is a plan view showing a cooling device adopted in the first embodiment.
• [ 6 ] 6 Fig. 14 is an end face view showing the cooling device adopted in the first embodiment
• [ 7 ] 7 14 is a flowchart showing a cooling simulation method according to a first embodiment.
• [ 8th ] 8th 14 is a flow chart showing a cooling simulation method according to a second embodiment.
• [ 9 ] 9 14 is a flow chart showing a cooling method for a workpiece according to a third embodiment.
• [ 10 ] 10 (a) Fig. 13 is a perspective transparent view showing a cooling device manufactured and adopted in a test example, and 10(b) 14 is a view showing the initial value of the workpiece surface temperature.
• [ 11 ] 11(a) 13 is a view showing the appearance of the coolant calculated in the test example, and 11(b) Fig. 14 is a view showing the flow velocity distribution.
• [ 12 ] 12 (a) and 12(b) are graphs with time as the transverse axis and temperature as the longitudinal axis, and showing the change in workpiece surface temperature, where 12 (a) the actual measured value and 12(b) shows the calculated value.

[Forms for carrying out the invention]

<First Embodiment>

An embodiment of the present invention is explained below with reference to the drawings.

1 (a) FIG. 12 is a block diagram showing a cooling simulation apparatus according to the present embodiment, and FIG 1 (b) Fig. 12 is a block diagram showing a computing section.

2 (a) and 2 B) 12 are views showing the operation of the cooling simulation apparatus according to the present embodiment, in which (a) shows a simulation of the heating process and (b) shows a simulation of the cooling process.

A cooling simulation apparatus 1 (hereinafter also simply referred to as “apparatus 1”) is an apparatus for predicting a temperature change inside a workpiece when the workpiece is brought into contact with a coolant, e.g. B. a device that simulates the cooling process of a quench. In this specification, the "workpiece" is a steel product that becomes the subject of quenching.

As in 1 (a) 1, an input/output section 10, an arithmetic section 20, and a memory section 30 are provided in the apparatus 1. As shown in FIG. As the device 1, either a general computer or a special computer can be used.

In the input/output section 10, for example, signal terminals or a communication device are provided to input data from the outside and output data to the outside. Data types described below are input into the input/output section 10, which include in particular various conditions of the cooling simulation, e.g. B. the shape of the workpiece, temperature and initial values of the workpiece, shape of the cooling jacket, physical properties of the coolant, flow rate of the coolant, etc. Also included are the shape of the cooling jacket, the size, number and arrangement of holes for ejecting the coolant. The data output from the input/output section 10 includes the result of cooling simulation. The input/output section 10 can also be connected to external devices such as a keyboard, a mouse, a display, an external storage device, and so on.

In the arithmetic section 20, for example, a CPU (central processing unit) is provided. The arithmetic section 20 reads out and executes a cooling simulation program stored in the storage section 30 . Concretely, the calculation section 20 calculates the flow rate of the coolant on the surface of the workpiece by heat flow simulation, acquires the heat transfer coefficient by calculation based on the temperature of the surface of the workpiece and the calculated flow rate of the coolant or by reading from the storage section 30, and calculates the temperature change of the surface of the workpiece by means of the acquired heat transfer coefficient.

In the storage section 30, storage means, e.g. B. an SSD (solid state drive), HDD (hard disk drive: hard disk drive), etc. are provided. The cooling simulation program is stored in the storage section 30. The cooling simulation program includes a heat flow simulation program. Also stored in the storage section 30 are a program for magnetic field analysis, a program for thermal analysis, a program for structural analysis, a program for stress/strain analysis, and a program for circuit analysis.

In the storage section 30, the relationship (hereinafter also referred to as “Tvh relationship”) among a temperature Ts of the surface of the workpiece (hereinafter also referred to as “workpiece surface temperature Ts”), the flow velocity v of the coolant, and the heat transfer coefficient h is stored . The Tvh relationship may be stored in the storage section 30 as a table, a formula, or in some other form. “Coefficient of heat transfer” is the amount of heat transferred at the interface between two types of objects per unit area, unit temperature, and unit time.

As in 1 (b) 1, the arithmetic section 20 includes a control section 21, a magnetic field analysis section 22, a heating amount calculation section 23, a heat treatment analysis section 24, a material value updating section 25, a circuit analysis section 26, and a heat flow analysis section 27. The control section 21, magnetic field analysis section 22, heating amount calculation section 23, heat treatment analysis section 24, material value update section 25, circuit analysis section 26 and heat flow analysis section 27 (hereinafter collectively referred to as “respective sections 21 to 27”) can each be constituted by an independent hardware resource or be formed virtually by running a program.

The control section 21 controls the respective sections 22 to 27, with an exchange of commands and data between the respective sections 22 to 27 as well as an exchange between the input/output section 10 and the memory section 30 taking place. Further, the control section 21 performs control of the number of repetitions of interaction analysis and times of steps, and temperature monitoring of certain portions. An "interaction analysis" is an analysis that takes into account complex mutual influences of a number of physical phenomena.

The magnetic field analysis section 22 performs magnetic field analysis based on Maxwell's equations of electromagnetism using the finite element method. Concretely, the magnetic field analysis section 22 calculates the magnetic flux distribution generated in the vicinity of a heating coil and due to the change of this distribution with time in eddy currents generated near the surface of the workpiece.

• Erstens gibt es durch Koordinaten als FEM-Modell für die Magnetfeldanalyse den Raum des Werkstücks, der Heizspule und deren Umgebung, der an den jeweiligen Knotenpunkten in eine Mehrzahl von Elementen unterteilt wurde, dargestellte Knotendaten, und Kombinationen der die jeweiligen Elemente bildenden Knotendaten (im Folgenden einfach als „Elementdaten“ bezeichnet).
• Zweitens gibt es die elektrische Leitfähigkeit und die relative magnetische Permeabilität je Metallstruktur, die jeweils von der Temperatur abhängen, als Materialeigenschaften bezüglich der jeweiligen Materialien des Werkstücks und der Heizspule.
• Drittens gibt es die Frequenz der hochfrequenten Induktionswärmequelle, den Heizspulenstrom oder die Heizspulenspannung als Daten bezüglich der Analysebedingungen.
• Viertens gibt es Temperaturdaten an den jeweiligen Knoten bei dem FEM-Modell für die Magnetfeldanalyse. Als Anfangswert dieser Temperaturdaten wird die Raumtemperatur eingegeben, und durch die Steuersektion 21 nacheinander überschrieben.

The magnetic field analysis section 22 divides the space of the workpiece, the heating coil and their surroundings into a plurality of elements. Therefore, the following types of data are input to the magnetic field analysis section 22:

• First, there are nodal data represented by coordinates as an FEM model for magnetic field analysis, the space of the workpiece, heating coil and their surroundings divided into a plurality of elements at the respective nodal points, and combinations of the nodal data constituting the respective elements (hereinafter referred to simply as "item data").
• Second, there are electrical conductivity and relative magnetic permeability per metal structure, each of which depends on temperature, as material properties related to the respective materials of the workpiece and the heating coil.
• Third, there is the frequency of the high-frequency induction heat source, the heating coil current, or the heating coil voltage as data on the analysis conditions.
• Fourth, there are temperature data at the respective nodes in the FEM model for magnetic field analysis. As the initial value of this temperature data, the room temperature is inputted and overwritten by the control section 21 one by one.

The magnetic field analysis section 22 adjusts the inflow/outflow area of the current or voltage at the cutting surface of the heating coil using the FEM model for the magnetic field analysis, obtains the magnetic flux distribution based on this adjustment, obtains the eddy current distribution based on the magnetic flux distribution, and calculates the Joule loss amount ( heating concentration amount). That is, the magnetic field analysis section 22 calculates the Joule loss amount per element in the FEM model for the magnetic field analysis. Then, the magnetic field analysis section 22 outputs data representing the Joule loss amount per element to the heating amount calculation section 23 .

The heating amount calculation section 23 calculates the heating amount of the respective elements based on the Joule loss amount of the respective elements inputted from the magnetic field analysis section 22 , and outputs it to the heat treatment analysis section 24 .
Information input to the heating amount calculation section 23 is the node data specified by the coordinates set for the workpiece and the element data, and both the node data and the element data per FEM model for magnetic field analysis and FEM model are defined for the heat treatment analysis. The heating amount calculation section 23 performs a mapping process of the nodal data and element data in the FEM model for the magnetic field analysis and the nodal data and element data in the model for the heat treatment analysis. The heating amount calculation section 23 obtains the heating amount of the respective elements in the FEM model for the heat treatment analysis and outputs it to the heat treatment analysis section 24 directly or via the control section 21 .

As in 2 (a) shown, the temperature, structure, stress/strain of the respective sections of the workpiece are related to each other. Therefore, through an interaction analysis of these mutual relationships, the heat treatment analysis section 24 can predict the temperature and strain of the respective nodes set in the FEM model for the heat treatment analysis, the stress of the respective members, the metal structure, and so on. For example, any portion of a tool will experience a phase transition as the temperature changes. On the other hand, a phase transition leads to the generation/absorption of latent heat. If a non-uniform phase transition occurs in the workpiece, this leads to stress due to local volume changes. On the other hand, the emergence of a phase transition is influenced by the emergence of stresses. When the workpiece is deformed, heat generation or heat absorption occurs at the deformation portion. If there is a temperature difference inside the workpiece, tension will arise. When tension occurs, strain occurs.

The heat treatment analysis section 24 divides the workpiece into a plurality of elements for interrelation analysis by the finite element method, and performs analysis per element relating temperature, elastoplastic structure and phase transition to each other. The heat treatment analysis section 24 performs analysis based on the heating amount per element inputted from the heating amount calculation section 23 using a heat conduction equation, etc., and calculates the temperature, deformation amount, stress/strain of the respective elements, and metal structure (metal structure volume fraction) at the respective nodes in the FEM model for the heat treatment analysis. The metal structure volume fraction pushes the steel structure z. B. the proportion of ferrite, pearlite, austenite, martensite, bainite, etc. from. Regarding stress/strain, data can also be exchanged per node instead of per element.

• Erstens gibt es durch Koordinaten als FEM-Modell für die Wärmebehandlungsanalyse bezüglich der Form und Abmessungen des Werkstücks dargestellte Knotendaten, und Kombinationen der die jeweiligen Elemente bildenden Knoten (Elementdaten).
• Zweitens gibt es als Materialeigenschaften des Stahls, aus dem das Werkstück besteht, Phasenübergang-Charakteristikdaten wie ein isothermen Zeit-Temperaturumwandlung-Schaubild (TTT: Time-Temperature-Transformation diagram), eine kontinuierliche Abkühlungsumwandlung-Kurve (CCT: Continuous-Cooling-Transformation diagram), Austenit-Transformation-Temperaturdaten (TTA: Time-Temperature-Austenization diagram), Martensit-Transformationstemperatur usw., Wärmeleitung-Charakteristikdaten bezüglich der Wärmeleitfähigkeit, spezifischen Wärme, Dichte und Umwandlungswärme und Spannung/Dehnungs-Materialeigenschaften wie das Youngsche Modul, die Poissonzahl, den linearen Ausdehnungskoeffizienten, die Fließgrenze, den Bearbeitung-Verfestigungskoeffizienten, die Transformation-Expansionsrate, den Transformation-Plastizitätskoeffizienten usw.
• Drittens wird als Information zur Annahme des Abkühlungsprozesses des Werkstücks der Wert des Wärmeübertragungskoeffizienten h als thermische Randbedingung an der Abkühlungsfläche des Werkstücks definiert. Der Wärmeübertragungskoeffizient h wird später erläutert.
• Viertens gibt es Informationen bezüglich der Erwärmungsmenge an den jeweiligen Knoten, die bei dem FEM-Modell für die Wärmebehandlungsanalyse festgelegt werden.
• Diese werden von der Erwärmungsmenge-Berechnungssektion 23 eingegeben.
• Fünftens gibt es als Informationen für die Analysebedingungen die Erwärmungszeit, Abkühlzeit, Interaktionshäufigkeit usw.

The following types of data are input to the heat treatment analysis section 24:

• First, there are node data represented by coordinates as an FEM model for heat treatment analysis regarding the shape and dimensions of the workpiece, and combinations of the nodes constituting the respective elements (element data).
• Second, as material properties of the steel constituting the workpiece, there are phase transition characteristic data such as an isothermal Time-Temperature-Transformation diagram (TTT), a continuous cooling transformation curve (CCT: Continuous-Cooling- Transformation diagram), austenite transformation temperature data (TTA: Time-Temperature-Austenization diagram), martensite transformation temperature, etc., heat conduction characteristic data in terms of thermal conductivity, specific heat, density and heat of transformation, and stress/strain material properties such as Young's modulus, Poisson's ratio, linear expansion coefficient, yield point, machining hardening coefficient, transformation expansion rate, transformation plasticity coefficient, etc.
• Third, as information for assuming the cooling process of the workpiece, the value of the heat transfer coefficient h is defined as a thermal boundary condition on the cooling surface of the workpiece. The heat transfer coefficient h will be explained later.
• Fourth, there is information on the amount of heating at each node set in the FEM model for the heat treatment analysis.
• These are input from the heating amount calculation section 23 .
• Fifth, as information for the analysis conditions, there is the heating time, cooling time, frequency of interaction, etc.

The heat treatment analysis section 24 outputs data representing the temperature at the respective nodes and the metal structure volume fraction of the respective elements in the FEM model for the heat treatment analysis to the material value updating section 25 directly or via the control section 21, and outputs data representing a deformation of the workpiece to the heat flow analysis section 27 directly or via the control section 21 .

When data representing the temperature at the respective nodes and the metal structure volume fraction of the respective elements in the FEM model for the heat treatment analysis is inputted from the heat treatment analysis section 24, the material value updating section 25 calculates the temperature at the respective nodes and the electric conductivity and relative magnetic permeability of the respective elements in the FEM model for the magnetic field analysis, and outputs them to the magnetic field analysis section 22 directly or via the control section 21. The temperature at each node, as well as the electrical conductivity and relative magnetic permeability of each element, affect the permeability depth.

The circuit analysis section 26 performs, for example, as a circuit simulation, a calculation using a circuit equation on the electric circuits of the high-frequency induction heat source and a matching device, and the high-frequency induction heat source and the heating coil, obtains the coil current or coil voltage, and outputs the result to the magnetic field analysis section 22 out of. This also allows changes over time in the induction heating phenomenon of the heating coil and the workpiece to be evaluated.

In a high-frequency quenching apparatus, electric power of a constant frequency is applied to the heating coil by means of an LCR resonance circuit, and the workpiece is heated with high-frequency induction. However, with a change in the heat distribution of the workpiece, the circuit load changes constantly, and the coil current, coil voltage and resonance frequency also change. In a control method for a high-frequency power source, either the coil current, the coil voltage, or the applied electric power is constantly controlled. In the present embodiment, since the analysis result of the magnetic field analysis section 22 forms the input data for the circuit analysis section 26, and the analysis result of the circuit analysis section 26 forms the input data for the magnetic field analysis section 22, the magnetic field analysis and the circuit analysis cooperate with each other, so that a high precision of the high-frequency deterrent simulation can be aimed for.

How 2 B) 12, the heat flow analysis section 27 performs heat flow simulation using computational fluid dynamics based on a structural model representing the configuration of a cooling device. The structural model includes information such as the shape of the water jacket, the shape of the workpiece, the positional relationship between the coolant spray nozzles on the water jacket and the workpiece, the direction in which the coolant is sprayed from the water jacket, etc.

Into the heat flux analysis section 27, data representing the physical properties of the refrigerant and the flow rate are inputted through the input/output section 10. Further, from the heat treatment analysis section 24, temperature data including the surface temperature of the workpiece and data representing the amount of change of the workpiece are input. Based on the input data, the heat flow analysis section 27 performs a flow analysis of the coolant by means of a heat flow simulation and calculates the Flow rate of the coolant on the surface of the workpiece. The heat flow analysis section 27 can also calculate the temperature and pressure of the coolant in addition to the flow rate of the coolant on the surface of the workpiece.

When the flow rate of the coolant on the surface of the workpiece is inputted from the heat flow analysis section 27, the control section 21 acquires the heat transfer coefficient h considering the relationship (Tvh relationship) stored in the storage section 30 between the workpiece surface temperature Ts, the flow rate v and of the heat transfer coefficient h and outputs it to the heat treatment analysis section 24 .

3 Fig. 13 is a graph in which the transverse axis shows the workpiece surface temperature Ts and the longitudinal axis shows the heat transfer coefficient h at the workpiece surface, and shows the relationship (Tvh relationship) between the workpiece surface temperature Ts, the coolant flow rate v and the heat transfer coefficient h shows.
3 is an example where water is used as the coolant. The tvh relationship is not on the in 3 example shown is limited. In the 3 The Tvh relationship shown can be determined experimentally or by a simulation, but it can also be determined by a model calculation. The heat transfer coefficient h at each workpiece surface temperature Ts and flow rate v is determined considering the boiling phenomenon of the coolant.

Next, the operation of the cooling simulation apparatus 1 according to the present embodiment, that is, the cooling simulation method according to the present embodiment will be explained.
In quenching the workpiece, a heating process and a cooling process are carried out consecutively. As described above, in the heating process, the workpiece is e.g. B. heated by high-frequency induction heating to a temperature greater than or equal to the austenite transformation temperature, and in the cooling process, the workpiece z. B. rapidly cooled by squirting out coolant.

The initial state of the cooling simulation can be defined by the heating simulation. For example, the initial value of the temperature of the surface of the workpiece and the initial value of the temperature inside the workpiece can be set by the heating simulation. A cooling simulation can also be carried out without performing a heating simulation. In this case, in the cooling simulation, the initial value of the temperature of the surface of the workpiece and the initial value of the temperature inside the workpiece are inputted from the outside.

First, the simulation of the heating process will be explained.
4 Fig. 12 is a flow chart showing the method of cooling simulation in the present embodiment.

As in 2 (a) and in step S91 of 4 1, various data are input to the arithmetic section 20 via the input/output section 10. FIG. The entered data can also be stored in the storage section 30.

Next, as shown in step S92, magnetic field analysis is performed by the magnetic field analysis section 22, which outputs the data representing the Joule loss amount per element to the heating amount calculation section 23. At this time, a circuit simulation is performed by the circuit analysis section 26 in cooperation with the magnetic field analysis section 22 .

Then, as shown in step S<b>93 , the heating amount calculation section 23 calculates the heating amount at the respective members and outputs it to the heat treatment analysis section 24 .

Then, as shown in step S<b>94 , the heat treatment analysis section 24 performs an interaction analysis, calculates the temperature at the respective nodes and the metal structure volume fraction of the respective elements, and outputs them to the material value updating section 25 .

Then, as shown in step S95, the material value updating section 25 calculates the temperature at the respective nodes and the electric conductivity and relative magnetic permeability of the respective elements, and updates the physical property data. Then, the updated physical property data is output to the magnetic field analysis section 22 .

As shown in step S96, so long as the interaction frequency has not reached an index number, processing returns to step S92. When the interaction frequency reaches the index number, the warming simulation ends.

By doing a heating simulation this way, there is one conclusion the state of the workpiece at the end of the heating process, ie the temperature distribution, the metal structure volume fraction distribution and the stress/strain distribution. This state of the workpiece can be specified as the initial state of the cooling simulation explained below.

Next, the simulation of the cooling process will be explained. First, a cooling method adopted in the present embodiment will be explained.
5 Fig. 12 is a plan view showing a cooling device adopted in the present embodiment.
6 Fig. 14 is an end face view showing the cooling device adopted in the present embodiment.

As in 5 and 6 1, a case 110 is provided in a cooling device 101 adopted in the present embodiment. Liquid supply lines 120 are connected to the housing 110 . The number of liquid supply lines 120 is arbitrary, with in 5 and 6 a four line example is shown. A cooling jacket 130 is provided in the housing 110 . The cooling jacket 130 has, for example, the shape of a tube extending in the vertical direction. A plurality of holes 131 are provided in the cooling jacket 130 . The holes 131 can be arranged regularly or also irregularly.

As described above, when the quenching treatment is performed on the workpiece 100, the workpiece 100 is heated to a temperature equal to or higher than the austenite transformation temperature by a method such as high-frequency induction heating, etc. Then, the workpiece 100 is placed inside the cooling jacket 130 and rotated. In this state, a coolant 200 is supplied to the inside of the housing 110 via the liquid supply lines 120 . The coolant 200 is z. B. to water. As the coolant 200 propagates in a gap 140 between the housing 110 and the water jacket 130 , it passes through the holes 131 of the water jacket 130 and is splashed onto the workpiece 100 . The contact of the coolant 200 with the workpiece 100 removes heat from the workpiece 100 and cools the workpiece 100 .

Next, the cooling simulation method will be explained. In the present embodiment, the above operation in which the coolant 200 comes into contact with the workpiece 100 and the workpiece 100 is cooled is simulated, and the temperature change of the respective portions of the workpiece is calculated.
7 FIG. 14 is a flow chart showing the method for cooling simulation according to the present embodiment.
7 12 mainly shows the cooperative operation of the heat flow analysis section 27 and the heat treatment analysis section 24 while omitting the other operation.

The conditions of the cooling simulation, e.g. B. the initial state of the workpiece, the shape of the cooling jacket, and the information of the coolant in the input / output section 10 of the device 1 input. The initial state of the workpiece includes e.g. B. the initial value of the temperature distribution inside the workpiece, the initial value of the temperature distribution of the surface of the workpiece, the initial value of the metal structure volume fraction distribution and the initial value of the stress/strain distribution. The initial state of the workpiece can be determined using the heating simulation described above, or it can be input from the outside. The coolant information includes the physical properties, temperature and flow rate of the coolant. The cooling simulation conditions are stored in the storage section 30 . The arithmetic section 20 reads out and executes a cooling simulation program stored in the storage section 30 . Thereby, the device 1 carries out a cooling simulation.

First, as in step S1 of FIG 7 1, the initial value of the surface temperature Ts of the workpiece from the storage section 30 enters. In the present simulation, at least with respect to a part of the workpiece 100, e.g. a portion to be quenched, a plurality of minute portions are set, and the initial value of the surface temperature Ts of the workpiece with respect to these minute portions is read. A part of the minute portions forms the surface of the workpiece 100.

Then, the heat flow analysis section 27 of the arithmetic section 20 as shown in FIG 2 B) and in step S2 of 7 shown a heat flow simulation. The heat flow simulation can be performed by different methods. In the present embodiment, the heat flow simulation z. B. by means of numerical fluid mechanics. This results in a flow analysis of the coolant 200 inside the cooling device 101. The flow velocity v of the coolant 200 on the surface of the workpiece 100 is thereby calculated.

In the present simulation, the surface of the workpiece 100 is divided into a plurality of minute areas, and the flow velocity v of the coolant 200 is calculated for the respective minute areas. That is, the distribution of the flow velocity v of the coolant 200 on the surface of the workpiece 100 is calculated. The flow velocity v is, for example, the velocity of the coolant 200 in a direction parallel to the surface of the workpiece 100 . The minute portions of the workpiece 100 and the minute areas of the surface may or may not correspond uniquely to each other. Furthermore, in addition to the flow velocity v of the coolant 200 on the surface of the workpiece 100, the distribution of the temperature Tq of the coolant 200 on the surface of the workpiece 100 and the distribution of the pressure P of the coolant 200 can also be calculated by the heat flow simulation.

Next, as shown in step S<b>3 , the arithmetic section 20 acquires the heat transfer coefficient h based on the initial value of the workpiece surface temperature Ts and the flow velocity v in consideration of the Tvh relationship stored in the storage section 30 . For example, when the Tvh relationship is stored as a table in the storage section 30, the arithmetic section 20 can determine the cell in the table corresponding to the initial value of the workpiece surface temperature Ts and the flow rate v and read out the value stored in that cell. When the Tvh relationship is stored in the storage section 30 as a formula, the calculation section 20 can calculate the heat transfer coefficient h by substituting the initial value of the workpiece surface temperature Ts and the flow rate v into this formula. The heat transfer coefficient h is also acquired per minute area. That is, the arithmetic section 20 acquires the distribution of the heat transfer coefficient h on the surface of the workpiece 100.

Next, as shown in step S4, the heat treatment analysis section 24 of the arithmetic section 20 calculates the temperature change of the workpiece 100 based on the heat transfer coefficient h. This calculation is carried out, for example, as described above, using an interaction analysis from a thermal analysis, structural analysis and stress/strain analysis. Thereby, the temperature change of the entire work 100 is calculated, and as a part thereof, a change amount ΔTs of the work surface temperature Ts is also calculated. However, the temperature change can be calculated by a method other than the interaction analysis described above.

Next, as shown in step S5, the workpiece surface temperature Ts after the temperature change is calculated. That is, (Ts + ΔTs) is regarded as a new workpiece surface temperature Ts.

Next, the processing returns from step S6 to step S1, and a new workpiece surface temperature Ts is read. Thus, the cooling simulation is continued by repeating steps S1 to S6. Then, when the interaction frequency reaches the index number, the cooling simulation is terminated.

In this way, in the cooling process, the change in temperature distribution inside the workpiece 100 and the metal structure distribution (metal structure volume fraction), residual stress distribution, hardness distribution, and strain amount of the workpiece 100 after the cooling process are calculated. Thereby, it can be judged whether the properties of the workpiece 100 after quenching meet the required level.

Next, the effects of the present embodiment will be explained.
In the present embodiment, the relationship (Tvh relationship) between the workpiece surface temperature Ts, the coolant flow rate v, and the heat transfer coefficient h is acquired in advance, and cooling simulation is performed using it, so calculation by modeling the boiling phenomenon is not required . That is, by acquiring the Tvh relation in advance, the heat transfer coefficient h of the workpiece surface can be acquired immediately by inputting the workpiece surface temperature Ts and the flow velocity v. As a result, a high-precision simulation can be carried out with a short computing time.

As in 3 shown, the higher the coolant flow rate, the larger the heat transfer coefficient becomes. Further, at the respective flow rates, the heat transfer coefficient has its maximum value in the vicinity of a workpiece surface temperature of 100°C, and the heat transfer coefficient decreases at both higher and lower temperatures. It is conceivable that the heat transfer coefficient increases as the temperature is higher, since water as a coolant does not boil in a temperature range where the workpiece surface temperature is considerably lower than 100°C.

On the other hand, boiling of the coolant starts in the vicinity of a workpiece surface temperature of 100°C. As the workpiece surface temperature increases, the boiling state changes from core boiling to transition boiling to film boiling. Therefore, it is conceivable that the heat transfer coefficient decreases because contact between the workpiece and the coolant is hindered by water vapor the higher the workpiece surface temperature is. As described above, the mechanism of the boiling phenomenon is complicated, but according to the present embodiment, since the heat transfer coefficient is a value combined with the boiling phenomenon, simulation of the boiling phenomenon itself is not required in the cooling simulation, so the calculation time can be shortened.

Further, according to the present embodiment, at the step S2 of 7 In the operation shown, the surface of the workpiece 100 is divided into a plurality of minute areas, and the workpiece surface temperature Ts and the flow rate v of the coolant are calculated per minute area. Thereby, in the operation shown in step S3, the heat transfer coefficient h per minute area can be acquired. Thereby, the temperature inside the workpiece 100 can be precisely calculated compared to using only one value as the heat transfer coefficient, and the cooling simulation precision can be greatly improved.

In addition, according to the present embodiment, as in 2 B) 1, the heat treatment analysis of the workpiece 100 is coupled to the heat flow analysis of the coolant 200. There is also a two-way feedback of data between the heat flow analysis and the heat treatment analysis. Furthermore, the heat treatment analysis is an interaction analysis of a heat analysis, structural analysis and stress/strain analysis. This enables a prediction of the hardness, strain magnitude and residual stress of the workpiece after quenching. Furthermore, because a deformation of the workpiece 100 in the cooling process is reported back to the heat flow analysis, influences that expand due to the deformation of the workpiece 100 on the flow of the coolant 200 can be taken into account. As a result, the precision of the cooling simulation can be further improved.

Furthermore, according to the present embodiment, the initial value of the cooling simulation can be set by the heating simulation. As a result, the precision of the cooling simulation can be further improved.

<Second embodiment>

8th FIG. 14 is a flow chart showing the method for cooling simulation according to the present embodiment.
As in 8th 1, in the present embodiment, as shown in step S12, the temperature Tq of the coolant on the workpiece surface and the pressure P of the coolant are also calculated by the heat flow simulation as shown in step S12, in addition to the flow velocity v of the coolant on the workpiece surface. Then, as shown in step S13, based on the workpiece surface temperature Ts, the flow rate v of the coolant, the temperature Tq of the coolant, and the pressure P of the coolant, the heat transfer coefficient h is acquired. In the storage section 30, the relationship among the workpiece surface temperature Ts, the flow rate v of the coolant, the temperature Tq of the coolant, the pressure P of the coolant, and the heat transfer coefficient h is stored.

For example, this relationship can be stored as a table or as a formula. In one formula, the heat transfer coefficient h is expressed as a function of the workpiece surface temperature Ts, the coolant flow rate v, the coolant temperature Tq, and the coolant pressure P, as in the following formula. $$\text{H}=\text{f}\left(\text{ts},\text{v},\text{Tq},\text{P}\right)$$

Other parameters can also be added to the above function to calculate the heat transfer coefficient h more precisely.
In the present embodiment, the steps are the same as the steps in the first embodiment except for the above steps.

According to the present embodiment, simulation with even higher precision can be enabled by calculating the heat transfer coefficient h in addition to the workpiece surface temperature Ts and the flow rate v of the coolant including the temperature Tq and the pressure P of the coolant 200 at the surface of the workpiece 100 is acquired. In the present embodiment, the structure, operation, and effects are the same as those in the first embodiment other than the above.

<Third embodiment>

Next, a cooling method for a workpiece using the cooling simulation method, program and apparatus described above will be explained.
9 14 is a flow chart showing a cooling method for a workpiece according to the present embodiment.

First, as in step S21 of 9 shown, assumed a plurality of cooling jackets having a different shape and prepared data representing the shape of the respective cooling jackets. For example, the cooling jackets adopted can take the form of the in 5 and 6 have cooling jackets 130 shown. The data showing the shape of the cooling jacket also includes, for example, the diameter and the axial length of the cooling jacket, as well as the size, number and arrangement of holes for ejecting the coolant.

Then, as in step S22 of 9 shown, using the data created in step S21, a cooling simulation, wherein the temperature change inside the workpiece is measured. This is the cooling simulation method explained in the first or second embodiment. The cooling simulation can be performed by the cooling simulation apparatus explained in the first embodiment or by executing a cooling simulation program on a general-purpose computer.

The cooling simulation program is a cooling simulation program for predicting a temperature change inside a workpiece when the surface of the heated workpiece is brought into contact with a coolant. In this cooling simulation program, the flow rate of the coolant on the surface of the workpiece is calculated on a computer through a flow analysis of the coolant using a heat flow simulation, and the temperature change inside the workpiece is calculated based on the temperature of the surface of the workpiece and the calculated flow rate.

Then, as in step S23 of 9 shown, based on the result of the cooling simulation executed in step S22, the optimal shape of the cooling jacket is determined. For example, based on the calculation result of the metal structure distribution (metal structure volume fraction), residual stress distribution, hardness distribution and deformation amount of the workpiece after cooling, the characteristics of the workpiece after cooling are evaluated and the cooling jacket is selected in which the characteristics of the workpiece are closest to the required characteristics are.

Then, as in step S24 of 9 shown, the cooling jacket having the optimum shape set in step S23 is actually made.

As in step S25 of 9 shown, the workpiece is then cooled by means of the cooling jacket produced in step S24. The workpiece is, for example, heated to a temperature greater than or equal to the austenite transformation temperature before cooling. Thereby, a quenching treatment can be performed on the workpiece.

According to the present embodiment, the cooling conditions, e.g. B. the shape of the cooling jacket, can be optimized inexpensively and in a short time. Thereby, high precision and high quality of a workpiece after a quenching treatment can be aimed for, for example, in the workpiece after cooling. For example, the shape of the workpiece after cooling is highly precise, and by controlling the residual stress, deformation can be suppressed and the desired surface state can be obtained.

In the present embodiment, an example was explained in which the shape of the cooling jacket was optimized as a cooling condition, but the optimization of the cooling conditions is not limited to this, and such as the physical properties of the coolant, the flow rate of the coolant, the temperature of the coolant, the positional relationship between the coolant spray nozzles on the cooling jacket and the workpiece, the direction in which the coolant is sprayed from the cooling jacket, etc.

<test sample>

Next, a test example showing the effect of the first embodiment will be explained.
10 (a) Fig. 13 is a perspective transparent view showing the cooling device adopted and manufactured in the present test example, and 10(b) 12 is a view showing the initial value of the workpiece surface temperature Ts.
11(a) 13 is a view showing the appearance of the coolant calculated in the present test example, and 11(b) Fig. 14 is a view showing the flow velocity distribution.

As in 10 (a) shown, the basic structure of a cooling device 103 assumed in the present test example is the same as that of FIG 5 and 6 The cooling device 101 shown in FIG. A cooling jacket 130 has a cylindrical shape with a height of 68 mm and an inner diameter of 140 mm. The number of holes 131 is 330 pieces, each hole 131 having a diameter of 2 mm.

A cylindrical rectifier plate 135 is provided between the cooling jacket 130 and the housing 110 . In the rectifier plate 135, 24 pieces of holes 136 are provided. Two holes 136 are arranged one above the other in 12 rows in the circumferential direction. The workpiece 100 has a ring shape with a height of 50 mm, an outer diameter of 100 mm and an inner diameter of 80 mm. Water is used as coolant 200 . The coolant 200 has a flow rate of 200 l/min and a temperature of 20 °C.

Under the above conditions, a heat flow simulation was performed using the method explained in the first embodiment. As in 11(a) 1, the coolant 200 has overflowed from the cooling device 103 and has spread over the entire side surface of the workpiece 100. FIG. As in 11(b) shown, the distribution of the flow velocity v of the coolant 200 has resulted in a distribution of the holes 131 of the cooling jacket 130 reflecting distribution.

Further, in the present experimental example, the cooling simulation explained in the first embodiment was performed and the temperature change was calculated. Furthermore, actual cooling was performed and the temperature change was measured. In the following, the result of the simulation is referred to as the "calculated value" and the value measured during actual cooling as the "actual measured value".

12 (a) and 12(b) are graphs with time as the transverse axis and temperature as the longitudinal axis, and showing the change in workpiece surface temperature, where 12 (a) the actual measured value and 12(b) shows the calculated value.

The initial temperature of the middle section 100b of the workpiece 100, as in 10(b) was set to 920°C and the initial temperature of the top portion 100a and the bottom portion 100c was set to 870°C. Furthermore, the rotation speed of the workpiece 100 was set at 200 rpm.

As in 12 (a) 1, in the actual measured value, the cooling speed is low during 0.5 second from the start of cooling, while the cooling speed increases after 0.5 second elapses. After 0.5 seconds have elapsed, the temperature of the upper section is lower than the temperature of the lower section at that time. As in 12(b) 1, also in the calculated value, the cooling speed is low during 0.5 second from the start of cooling, while the cooling speed increases after 0.5 second elapses. After 0.5 seconds have elapsed, the temperature of the upper section is lower than the temperature of the lower section at that time. In the present test example, the cooling behavior of the actual measured value and the calculated value therefore essentially match.

The respective embodiments described above are concrete examples of the present invention, and the present invention is not limited to these embodiments. For example, the present invention also includes embodiments in which various components are added to, omitted from, or changed from the above-described embodiments.

• [Nachtrag 1] Ein Verfahren zur Abkühlungssimulation, um eine Temperaturänderung im Inneren eines Werkstücks bei einem Kontakt der Oberfläche des erwärmten Werkstücks mit einem Kühlmittel zu prognostizieren, wobei durch eine Strömungsanalyse des Kühlmittels mittels einer Wärmeflusssimulation die Strömungsgeschwindigkeit des Kühlmittels auf der Oberfläche des Werkstücks berechnet wird, und basierend auf der Temperatur der Oberfläche des Werkstücks und der berechneten Strömungsgeschwindigkeit die Temperaturänderung im Inneren des Werkstücks berechnet wird.
• [Nachtrag 2] Ein Verfahren zur Abkühlungssimulation nach Nachtrag 1, wobei basierend auf der Temperatur der Oberfläche des Werkstücks und der Strömungsgeschwindigkeit ein Wärmeübertragungskoeffizient bei der Oberfläche des Werkstücks geschätzt wird, und mittels des Wärmeübertragungskoeffizienten die Temperaturänderung im Inneren des Werkstücks berechnet wird.
• [Nachtrag 3] Ein Verfahren zur Abkühlungssimulation nach Nachtrag 2, wobei der Wert des Wärmeübertragungskoeffizienten ein unter Berücksichtigung des Siedephänomens des Kühlmittels festgelegter Wert ist.
• [Nachtrag 4] Ein Verfahren zur Abkühlungssimulation nach Nachtrag 1, wobei durch die Wärmeflusssimulation auch die Temperatur des Kühlmittels auf der Oberfläche des Werkstücks und der Druck des Kühlmittels berechnet wird, und basierend auf der Temperatur der Oberfläche des Werkstücks, der Strömungsgeschwindigkeit des Kühlmittels, der Temperatur des Kühlmittels und des Drucks des Kühlmittels die Temperaturänderung im Inneren des Werkstücks berechnet wird.
• [Nachtrag 5] Ein Verfahren zur Abkühlungssimulation nach Nachtrag 4, wobei basierend auf der Temperatur der Oberfläche des Werkstücks, der Strömungsgeschwindigkeit des Kühlmittels, der Temperatur des Kühlmittels und des Drucks des Kühlmittels der Wärmeübertragungskoeffizient bei der Oberfläche des Werkstücks geschätzt wird, und mittels des Wärmeübertragungskoeffizienten die Temperaturänderung im Inneren des Werkstücks berechnet wird.
• [Nachtrag 6] Ein Verfahren zur Abkühlungssimulation nach einem der Nachträge 1 bis 5, wobei bei der Berechnung der Temperaturänderung im Inneren des Werkstücks auch die Struktur, Spannung und Dehnung des Werkstücks berechnet werden.
• [Nachtrag 7] Ein Verfahren zur Abkühlungssimulation nach Nachtrag 6, wobei eine Verformung des Werkstücks der Wärmeflusssimulation rückgemeldet wird.
• [Nachtrag 8] Ein Verfahren zur Abkühlungssimulation nach einem der Nachträge 1 bis 7, wobei eine Temperaturänderung im Inneren des Werkstücks der Wärmeflusssimulation rückgemeldet wird.
• [Nachtrag 9] Ein Verfahren zur Abkühlungssimulation nach einem der Nachträge 1 bis 8, wobei der Anfangswert der Temperatur der Oberfläche des Werkstücks und der Anfangswert der Temperatur im Inneren des Werkstücks durch eine Simulation bei einer hochfrequenten Induktionserwärmung des Werkstücks ermittelt wird.
• [Nachtrag 10] Ein Programm zur Abkühlungssimulation, um eine Temperaturänderung im Inneren eines Werkstücks bei einem Kontakt der Oberfläche des erwärmten Werkstücks mit einem Kühlmittel zu prognostizieren, wobei auf einem Computer die Strömungsgeschwindigkeit des Kühlmittels auf der Oberfläche des Werkstücks durch eine Strömungsanalyse des Kühlmittels mittels einer Wärmeflusssimulation berechnet wird, und die Temperaturänderung im Inneren des Werkstücks basierend auf der Temperatur der Oberfläche des Werkstücks und der berechneten Strömungsgeschwindigkeit berechnet wird.
• [Nachtrag 11] Eine Vorrichtung zur Abkühlungssimulation, um eine Temperaturänderung im Inneren eines Werkstücks bei einem Kontakt der Oberfläche des erwärmten Werkstücks mit einem Kühlmittel zu prognostizieren, wobei die Vorrichtung zur Abkühlungssimulation eine Rechensektion umfasst, welche die Strömungsgeschwindigkeit des Kühlmittels auf der Oberfläche des Werkstücks durch eine Strömungsanalyse des Kühlmittels mittels einer Wärmeflusssimulation berechnet, und die Temperaturänderung im Inneren des Werkstücks basierend auf der Temperatur der Oberfläche des Werkstücks und der berechneten Strömungsgeschwindigkeit berechnet.
• [Nachtrag 12] Eine Vorrichtung zur Abkühlungssimulation nach Nachtrag 11, die ferner eine Speichersektion umfasst, in welcher die Beziehung zwischen der Temperatur der Oberfläche des Werkstücks, der Strömungsgeschwindigkeit des Kühlmittels und des Wärmeübertragungskoeffizienten bei der Oberfläche gespeichert ist, und die Rechensektion den Wärmeübertragungskoeffizienten basierend auf der Temperatur der Oberfläche des Werkstücks und der berechneten Strömungsgeschwindigkeit von der Speichersektion erwirbt und mittels des ausgelesenen Wärmeübertragungskoeffizienten die Temperaturänderung im Inneren des Werkstücks berechnet.
• [Nachtrag 13] Ein Kühlverfahren für ein Werkstück, umfassend einen Schritt zum Festlegen von Kühlbedingungen mittels eines Verfahrens zur Abkühlungssimulation nach einem der Nachträge 1 bis 9, und einen Schritt zum Kühlen des Werkstücks mittels der festgelegten Kühlbedingungen.
• [Nachtrag 14] Ein Kühlverfahren für ein Werkstück nach Nachtrag 13, wobei die Kühlbedingungen die Form des Kühlmantels umfassen, und in dem Schritt zum Kühlen des Werkstücks ein Kühlmantel mit der Form verwendet wird, die in dem Schritt zum Festlegen der Kühlbedingungen festgelegt wurde.

The present invention includes the following aspects:

• [Addendum 1] A cooling simulation method for predicting a temperature change inside a workpiece when the surface of the heated workpiece comes into contact with a coolant, wherein the flow rate of the coolant on the surface of the workpiece is calculated through a flow analysis of the coolant using a heat flow simulation , and based on the temperature of the surface of the workpiece and the calculated flow rate, the temperature change inside the workpiece is calculated.
• [Addendum 2] A cooling simulation method according to Addendum 1, wherein a heat transfer coefficient at the surface of the workpiece is estimated based on the temperature of the surface of the workpiece and the flow velocity, and the temperature change inside the workpiece is calculated using the heat transfer coefficient.
• [Addendum 3] A cooling simulation method according to Addendum 2, wherein the value of the heat transfer coefficient is a value set in consideration of the boiling phenomenon of the refrigerant.
• [Addendum 4] A cooling simulation method according to Addendum 1, wherein the temperature of the coolant on the surface of the workpiece and the pressure of the coolant are also calculated through the heat flow simulation, and based on the temperature of the surface of the workpiece, the flow rate of the coolant, the temperature of the coolant and the pressure of the coolant, the temperature change inside the workpiece is calculated.
• [Addendum 5] A cooling simulation method according to Addendum 4, wherein based on the temperature of the surface of the workpiece, the flow rate of the coolant, the temperature of the coolant and the pressure of the coolant, the heat transfer coefficient at the surface of the workpiece is estimated, and using the heat transfer coefficient the temperature change inside the workpiece is calculated.
• [Addendum 6] A cooling simulation method according to any one of Addendums 1 to 5, wherein when the temperature change inside the workpiece is calculated, the structure, stress and strain of the workpiece are also calculated.
• [Addendum 7] A cooling simulation method according to Addendum 6, wherein a deformation of the workpiece is fed back to the heat flow simulation.
• [Addendum 8] A cooling simulation method according to any one of Addendums 1 to 7, wherein a temperature change inside the workpiece is fed back to the heat flow simulation.
• [Addendum 9] A cooling simulation method according to any one of Addendums 1 to 8, wherein the initial value of the temperature of the surface of the workpiece and the initial value of the temperature inside the workpiece are obtained by a simulation of high-frequency induction heating of the workpiece.
• [Addendum 10] A cooling simulation program for predicting a temperature change inside a workpiece when the surface of the heated workpiece comes into contact with a coolant, wherein the flow rate of the coolant on the surface of the workpiece is calculated on a computer by a flow analysis of the coolant using a Heat flow simulation is calculated, and the temperature change inside the workpiece is calculated based on the temperature of the surface of the workpiece and the calculated flow rate.
• [Addendum 11] A cooling simulation apparatus for predicting a temperature change inside a workpiece upon contact of the surface of the heated workpiece with a coolant, the cooling simulation apparatus comprising a computing section which calculates the flow velocity of the coolant on the surface of the workpiece calculates a flow analysis of the coolant using a heat flow simulation, and calculates the temperature change inside the workpiece based on the temperature of the surface of the workpiece and the calculated flow rate.
• [Addendum 12] A cooling simulation apparatus according to Addendum 11, further comprising a storage section in which the relationship between the temperature of the surface of the workpiece, the flow rate of the coolant and the heat transfer coefficient at the surface is stored, and the arithmetic section calculates the heat transfer coefficient based on the temperature of the surface of the workpiece and the calculated flow rate from the accumulating section and calculates the temperature change inside the workpiece using the read heat transfer coefficient.
• [Addendum 13] A cooling method for a work, comprising a step of setting cooling conditions by a cooling simulation method according to any one of Addendums 1 to 9, and a step of cooling the work by the set cooling conditions.
• [Addendum 14] A cooling method for a workpiece according to Addendum 13, wherein the cooling conditions include the shape of the cooling jacket, and in the step of cooling the workpiece, a cooling jacket having the shape specified in the step of determining the cooling conditions is used.

Reference List

1

Cooling simulation device

10

input/output section

20

calculation section

21

control section

22

magnetic field analysis section

23

Heating Amount Calculation Section

24

Heat treatment analysis section

25

Material value update section

26

circuit analysis section

27

Heat flow analysis section

30

storage section

100

workpiece

100a

upper section

100b

middle section

100c

lower section

101, 103

cooler

110

Housing

120

liquid supply line

130

cooling jacket

131

Hole

135

rectifier plate

136

Hole

140

Space

200

coolant

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• JP 2010230331A [0004]

Claims (14)

Method for cooling simulation to predict a temperature change inside a workpiece when the surface of the heated workpiece comes into contact with a coolant, wherein the flow rate of the coolant on the surface of the workpiece is calculated by means of a flow analysis of the coolant using a heat flow simulation, and based on the Temperature of the surface of the workpiece and the calculated flow rate the temperature change inside the workpiece is calculated. Method for cooling simulation according to claim 1 , wherein a heat transfer coefficient at the surface of the workpiece is estimated based on the temperature of the surface of the workpiece and the flow velocity, and the temperature change inside the workpiece is calculated using the heat transfer coefficient. Method for cooling simulation according to claim 2 , where the value of the heat transfer coefficient is a value set in consideration of the boiling phenomenon of the refrigerant. Method for cooling simulation according to claim 1 , through the heat flow simulation, the temperature of the coolant on the surface of the workpiece and the pressure of the coolant are also calculated, and based on the temperature of the surface of the workpiece, the flow rate of the coolant, the temperature of the coolant and the pressure of the coolant, the temperature change in the inside the workpiece is calculated. Method for cooling simulation according to claim 4 , wherein based on the temperature of the surface of the workpiece, the flow rate of the coolant, the temperature of the coolant and the pressure of the coolant, the heat transfer coefficient at the surface of the workpiece is estimated, and the temperature change inside the workpiece is calculated using the heat transfer coefficient. Method for cooling simulation according to claim 1 , where when calculating the temperature change inside the workpiece, the structure, stress and strain of the workpiece are also calculated. Method for cooling simulation according to claim 6 , whereby a deformation of the workpiece is fed back to the heat flow simulation. Method for cooling simulation according to one of Claims 1 until 7 , whereby a temperature change inside the workpiece is fed back to the heat flow simulation. Method for cooling simulation according to claim 1 , wherein the initial value of the temperature of the surface of the workpiece and the initial value of the temperature inside the workpiece are obtained by a simulation of high-frequency induction heating of the workpiece. A cooling simulation program for predicting a temperature change inside a workpiece when the surface of the heated workpiece comes into contact with a coolant, wherein the flow rate of the coolant on the surface of the workpiece is calculated on a computer by a flow analysis of the coolant using a heat flow simulation, and the temperature change inside the workpiece is calculated based on the temperature of the surface of the workpiece and the calculated flow rate. A cooling simulation apparatus for predicting a temperature change inside a workpiece upon contact of the surface of the heated workpiece with a coolant, the cooling simulation apparatus comprising a computing section which calculates the flow velocity of the coolant on the surface of the workpiece through a flow analysis of the coolant a heat flow simulation, and the temperature change inside the workpiece is calculated based on the temperature of the surface of the workpiece and the calculated flow rate. Cooling simulation device claim 11 further comprising a storage section in which the relationship between the temperature of the surface of the workpiece, the flow rate of the coolant and the heat transfer coefficient at the surface is stored, and the calculating section calculates the heat transfer coefficient based on the temperature of the surface of the workpiece and the calculated flow rate of of the storage section and calculates the temperature change inside the workpiece using the read heat transfer coefficient. A cooling method for a workpiece, comprising a step of setting cooling conditions by a cooling simulation method claim 1 , and a step of cooling the workpiece using the specified cooling conditions. Cooling process for a workpiece Claim 13 wherein the cooling conditions include the shape of the cooling jacket, and in the step of cooling the workpiece, a cooling jacket having the shape set in the step of setting the cooling conditions is used.

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