Thermal conductivity measurement is pivotal in numerous industries, and COMPARE.EDU.VN offers comprehensive comparisons to help professionals and researchers select the best methods. A Common Comparative Method For Measuring Thermal Conductivity, known as the direct or calibrated method, utilizes reference materials with known properties for comparison. This approach provides valuable insights but also presents unique challenges that COMPARE.EDU.VN expertly addresses, simplifying the selection process.
1. Understanding Thermal Conductivity
Thermal conductivity, fundamentally, describes a material’s intrinsic ability to conduct heat. It is a crucial parameter in designing and engineering materials for various thermal management applications. Industries relying on accurate thermal conductivity values include aerospace, automotive, construction, electronics, and energy. Understanding thermal conductivity is paramount for optimizing thermal management systems, improving energy efficiency, ensuring safety, guiding material selection, and fostering innovation.
1.1. The Role of Thermal Conductivity in Engineering
In engineering, thermal conductivity dictates how well a material can transfer heat, influencing design decisions in numerous applications:
- Heat Sinks: High thermal conductivity materials are essential for efficient heat dissipation in electronic devices.
- Insulation: Low thermal conductivity materials are used in building insulation to minimize heat transfer.
- Heat Exchangers: Thermal conductivity is critical in designing efficient heat exchangers for power generation and chemical processing.
1.2. Importance of Accurate Thermal Conductivity Measurements
Accurate measurement of thermal conductivity is vital for ensuring the reliability and performance of engineered systems. Inaccurate measurements can lead to suboptimal designs, overheating, energy inefficiencies, and even safety hazards. For example, using a material with a lower-than-expected thermal conductivity in a heat sink could result in device failure due to overheating.
2. Absolute vs. Direct (Comparative) Methods: An Overview
There are two primary approaches to measuring thermal conductivity: absolute and direct (comparative) methods. Absolute methods determine thermal conductivity without relying on reference materials, while direct methods compare the thermal properties of a sample to those of a known standard. Understanding the differences between these methods is essential for selecting the appropriate measurement technique.
2.1. Absolute Methods
Absolute methods measure thermal conductivity based on fundamental physical principles, without the need for calibration against known standards. These methods are often considered more accurate but can be complex and time-consuming. Examples of absolute methods include the Guarded Hot Plate (GHP) method and the Transient Plane Source (TPS) method.
2.2. Direct (Comparative) Methods
Direct, or comparative, methods involve comparing the thermal response of a sample to that of a reference material with known thermal conductivity. This approach is typically faster and more straightforward than absolute methods, but its accuracy depends on the accuracy of the reference material. Common direct methods include the Transient Hot Wire (THW) method, the Heat Flow Meter (HFM) method, and the Guarded Comparative Longitudinal Heat Flow (GCLHF) method.
3. A Deep Dive into Direct (Comparative) Thermal Conductivity Measurement
Direct thermal conductivity measurement, also known as the comparative method, involves using one or more calibration reference materials to determine the thermal conductivity of an unknown sample. This method contrasts with absolute measurements, which do not rely on calibration materials and are considered to provide the highest accuracy. The accuracy of the direct or comparative approach is a composite value based on the accuracy of the absolute method used to measure the reference materials and the comparative device itself.
3.1. The Process of Direct Thermal Conductivity Measurement
The process typically involves several key steps:
- Selection of Calibration Materials: Choosing a material with a known thermal conductivity as a reference is crucial. The accuracy of the direct measurement depends significantly on the known properties of this calibration material.
- Measurement Setup: The sample and the calibration material are subjected to similar conditions with a known amount of heat applied. The specific setup varies depending on the method used but generally involves placing the sample and reference material in a way that allows for controlled heat flow.
- Heat Application and Data Collection: The response of both the sample and the calibration material is monitored while heat is applied. This can involve measuring the temperature change over time or the steady-state temperature distribution within the materials.
- Comparison and Calculation: The thermal response of the sample is directly compared to that of the calibration material. Since the thermal conductivity of the calibration material is known, the thermal conductivity of the sample can be determined by analyzing the differences in their thermal responses under the same conditions.
- Error Analysis: Efforts are made to ensure equal heat flow between the calibration material and the sample to achieve the best accuracy. The composite accuracy of the result is influenced by the precision of the absolute method used to measure the reference materials and the comparative device itself.
3.2. Key Considerations for Direct Methods
When using direct methods, several factors must be carefully considered:
- Reference Material Accuracy: The accuracy of the reference material is paramount. It should be traceable to national or international standards.
- Contact Resistance: Minimizing contact resistance between the sample, the reference material, and the measuring device is crucial for accurate measurements.
- Heat Flow Uniformity: Ensuring uniform heat flow through the sample and reference material is essential for reliable results.
- Temperature Control: Maintaining stable and uniform temperature conditions is critical for accurate measurements, particularly in steady-state methods.
4. Advantages of Direct Thermal Conductivity Measurements
Direct thermal conductivity measurements offer several advantages over absolute methods, making them suitable for a wide range of applications. These advantages include consistency, accuracy, traceability, and quality assurance.
4.1. Consistency in Measurement Results
Calibrated results are more consistent across different measurements or experiments because they are adjusted to a common scale or reference point. This consistency enhances the reliability of the data and makes it easier to compare results obtained from different sources or instruments. Consistency is crucial in quality control and research, where reliable and reproducible results are essential.
4.2. Enhanced Accuracy through Calibration
Calibration helps to correct systematic errors or biases in measurements, leading to more accurate results. By calibrating instruments or models against known standards, researchers can ensure that their measurements are as accurate as possible. This is particularly important in applications where even small errors can have significant consequences.
4.3. Traceability to International Standards
Calibrated results are typically traceable to national or international standards, providing a clear lineage of measurements. This traceability enhances the credibility and trustworthiness of the results, especially in fields where accuracy is critical, such as metrology, environmental monitoring, and healthcare. Traceability ensures that measurements are comparable and consistent across different laboratories and regions.
4.4. Quality Assurance and Reliability
Calibration is an essential component of quality assurance processes, ensuring that instruments and measurement systems perform reliably and consistently over time. By regularly calibrating instruments, organizations can maintain the quality and reliability of their measurements, reducing the risk of errors and ensuring compliance with regulatory requirements. Quality assurance is vital in manufacturing, where consistent product quality is essential for customer satisfaction and regulatory compliance.
5. Disadvantages of Direct Thermal Conductivity Measurement
Despite the numerous advantages, direct thermal conductivity measurements also have some drawbacks. These include being time-consuming, requiring complex testing devices, potential measurement uncertainties, difficulties in measuring heat loss, and influence of external factors.
5.1. Time-Consuming Measurement Process
Some steady-state methods, like the Guarded Hot Plate (GHP), can be very time-consuming because they require the system to reach a steady-state condition before measurements can be taken, which can slow down the overall process. This can be a significant limitation in industrial settings where rapid measurements are needed for quality control.
5.2. Complex Testing Devices and Setup
A well-engineered experimental setup is usually needed to achieve high accuracy, which can lead to increased costs and the need for specialized knowledge to operate a complex device. The complexity of the equipment can also make it challenging to troubleshoot and maintain.
5.3. Measurement Uncertainties and Errors
High measurement uncertainties can be associated with some methods, particularly when dealing with high thermal conductivity materials, because the influence of contact resistances becomes larger, affecting the reliability of the thermal conductivity values obtained. This can limit the precision of the measurements and make it difficult to compare results across different experiments.
5.4. Difficulty in Measuring and Mitigating Heat Loss
Determining heat loss can be difficult with steady-state methods, especially at high temperatures, which can affect the accuracy of the thermal conductivity measurements. Heat losses from the device, particularly in parallel plate and concentric cylinder methods, can introduce errors that are hard to quantify and correct.
5.5. Influence of External Factors on Results
The thermal properties of fluids can be more challenging to study experimentally due to the presence of convective and radiative energy transport unless measures are taken to limit these processes. Additionally, forming an insulating boundary layer can result in an apparent reduction in the thermal conductivity, complicating measurements. External factors such as ambient temperature fluctuations and vibrations can also affect the accuracy of the measurements.
6. Common Comparative Methods in Detail
Several comparative methods are widely used for measuring thermal conductivity, each with its own advantages and limitations. These methods include the Transient Line Source (TLS), Transient Hot Wire (THW), Transient Hot Strip (THS), Modified Transient Plane Source (MTPS), Heat Flow Meter (HFM), Guarded Comparative Longitudinal Heat Flow (GCLHF), and Guarded Heat Flow Meter (GHFM).
6.1. Transient Line Source (TLS)
The Transient Line Source (TLS) method, standardized as ASTM D5334, is commonly used for testing soils and similar materials. This method requires a single or multi-point calibration with reference materials of similar thermal conductivity tested by an absolute method like the TPS.
- Principle: A thin wire is inserted into the sample, and a constant heat flux is applied. The temperature rise of the wire is measured over time, and the thermal conductivity is calculated from the slope of the temperature-time curve.
- Advantages: Simple setup, relatively fast measurement.
- Limitations: Requires good contact between the wire and the sample, sensitive to moisture content in soils.
6.2. Transient Hot Wire (THW)
The Transient Hot Wire (THW) method, standardized as ASTM D-7896, is used for testing liquids. This method requires a single-point calibration with a reference material of similar thermal conductivity tested by an absolute method like the TPS.
- Principle: A thin wire is immersed in the liquid, and a constant heat flux is applied. The temperature rise of the wire is measured over time, and the thermal conductivity is calculated from the slope of the temperature-time curve.
- Advantages: Suitable for a wide range of liquids, relatively fast measurement.
- Limitations: Requires good contact between the wire and the liquid, sensitive to convection effects.
6.3. Transient Hot Strip (THS)
The Transient Hot Strip (THS) method is used for testing solids. This method requires a single-point calibration with a similar thermal conductivity reference material tested by an absolute method like the TPS.
- Principle: A thin strip of metal is placed on the surface of the sample, and a constant heat flux is applied. The temperature rise of the strip is measured over time, and the thermal conductivity is calculated from the slope of the temperature-time curve.
- Advantages: Non-destructive, suitable for thin samples.
- Limitations: Requires good contact between the strip and the sample, sensitive to surface roughness.
6.4. Modified Transient Plane Source (MTPS)
The Modified Transient Plane Source (MTPS) method is used for testing solids and small particle powders. It requires a multi-point calibration with reference materials of similar thermal conductivity tested by an absolute method like the TPS.
- Principle: A sensor with a heating element and a temperature sensor is placed on the surface of the sample. A controlled heat pulse is applied, and the temperature response is measured. The thermal conductivity is calculated from the temperature response.
- Advantages: Fast measurement, suitable for a wide range of materials.
- Limitations: Requires good contact between the sensor and the sample, sensitive to surface roughness.
6.5. Heat Flow Meter (HFM)
The Heat Flow Meter (HFM) method, standardized as ASTM C518, is used for testing low thermal conductivity materials. This method requires a single-point calibration with similar thermal conductivity reference materials tested by an absolute method like the TPS or Guarded Hot Plate (GHP).
- Principle: A sample is placed between two plates maintained at different temperatures. The heat flow through the sample is measured using a heat flux sensor. The thermal conductivity is calculated from the heat flow, the temperature difference, and the sample thickness.
- Advantages: Simple setup, suitable for large samples.
- Limitations: Requires steady-state conditions, sensitive to contact resistance.
6.6. Guarded Comparative Longitudinal Heat Flow (GCLHF)
The Guarded Comparative Longitudinal Heat Flow (GCLHF) method, standardized as ASTM E1225, is used for testing ceramics, polymers, and metals. This method requires a single-point calibration with similar thermal conductivity reference materials tested by an absolute method like the TPS.
- Principle: A sample is placed in series with a reference material of known thermal conductivity. Heat is applied to one end of the assembly, and the temperature gradient is measured along the sample and the reference material. The thermal conductivity of the sample is calculated by comparing its temperature gradient to that of the reference material.
- Advantages: Suitable for a wide range of materials, reduces heat losses.
- Limitations: Requires good thermal contact between the sample and the reference material, complex setup.
6.7. Guarded Heat Flow Meter (GHFM)
The Guarded Heat Flow Meter (GHFM) method, standardized as ASTM E1530, is used for testing solids. This method requires a single-point calibration with a similar thermal conductivity reference material tested by an absolute method like the TPS.
- Principle: Similar to the HFM method, but with additional guarding to minimize heat losses. A sample is placed between two plates maintained at different temperatures, and the heat flow through the sample is measured using a heat flux sensor. The guarding ensures that all the heat flows through the sample, improving the accuracy of the measurement.
- Advantages: High accuracy, suitable for a wide range of materials.
- Limitations: Complex setup, requires steady-state conditions.
7. Factors Affecting the Accuracy of Comparative Methods
Several factors can influence the accuracy of comparative methods for measuring thermal conductivity. These include the accuracy of the reference material, contact resistance, heat flow uniformity, temperature control, sample preparation, and environmental conditions.
7.1. Accuracy of the Reference Material
The accuracy of the reference material is paramount. The reference material should be well-characterized and traceable to national or international standards. Any uncertainty in the thermal conductivity of the reference material will directly affect the accuracy of the measurement.
7.2. Contact Resistance
Contact resistance between the sample, the reference material, and the measuring device can significantly affect the accuracy of the measurement. Good thermal contact is essential for ensuring that heat flows uniformly through the sample and the reference material.
7.3. Heat Flow Uniformity
Ensuring uniform heat flow through the sample and reference material is crucial for reliable results. Non-uniform heat flow can lead to errors in the measurement of the temperature gradient and the heat flux.
7.4. Temperature Control
Maintaining stable and uniform temperature conditions is critical for accurate measurements, particularly in steady-state methods. Temperature fluctuations can introduce errors in the measurement of the temperature gradient and the heat flux.
7.5. Sample Preparation
Proper sample preparation is essential for ensuring accurate measurements. The sample should be clean, free of defects, and have a smooth surface. The dimensions of the sample should be accurately measured to calculate the thermal conductivity.
7.6. Environmental Conditions
Environmental conditions such as ambient temperature, humidity, and air currents can affect the accuracy of the measurement. It is important to control these conditions or to correct for their effects.
8. Applications of Direct Thermal Conductivity Measurement
Direct thermal conductivity measurement is used in a wide range of applications, including materials science, engineering, quality control, and research. These applications span across various industries, including aerospace, automotive, construction, electronics, and energy.
8.1. Materials Science and Engineering
In materials science and engineering, direct thermal conductivity measurement is used to characterize the thermal properties of new materials, optimize material compositions, and design materials for specific applications. This includes measuring the thermal conductivity of polymers, ceramics, metals, composites, and nanomaterials.
8.2. Quality Control in Manufacturing
In manufacturing, direct thermal conductivity measurement is used to ensure the quality of products and to verify that materials meet specified thermal performance requirements. This includes measuring the thermal conductivity of insulation materials, heat sinks, heat exchangers, and electronic components.
8.3. Research and Development
In research and development, direct thermal conductivity measurement is used to investigate the thermal properties of materials under different conditions, to develop new measurement techniques, and to validate theoretical models. This includes measuring the thermal conductivity of materials at high temperatures, low temperatures, and under different pressures.
8.4. Aerospace Industry Applications
The aerospace industry relies heavily on accurate thermal conductivity measurements for designing efficient thermal management systems for aircraft and spacecraft. High thermal conductivity materials are used in heat sinks for electronic components, while low thermal conductivity materials are used in insulation to protect against extreme temperatures.
8.5. Automotive Industry Applications
In the automotive industry, thermal conductivity measurements are used to optimize the performance of engines, cooling systems, and exhaust systems. High thermal conductivity materials are used in engine blocks and cylinder heads to dissipate heat, while low thermal conductivity materials are used in exhaust systems to reduce heat loss.
8.6. Construction Industry Applications
The construction industry uses thermal conductivity measurements to design energy-efficient buildings. Low thermal conductivity materials are used in insulation to reduce heat transfer through walls, roofs, and floors, minimizing energy consumption for heating and cooling.
8.7. Electronics Industry Applications
The electronics industry relies on accurate thermal conductivity measurements for designing efficient heat sinks for electronic components. High thermal conductivity materials are used to dissipate heat from microprocessors, power amplifiers, and other heat-generating components, preventing overheating and ensuring reliable performance.
8.8. Energy Industry Applications
In the energy industry, thermal conductivity measurements are used to optimize the performance of heat exchangers, power plants, and renewable energy systems. High thermal conductivity materials are used in heat exchangers to maximize heat transfer, while low thermal conductivity materials are used in insulation to minimize heat loss.
9. Recent Advances in Direct Thermal Conductivity Measurement
Recent advances in direct thermal conductivity measurement have focused on improving the accuracy, speed, and versatility of the techniques. These advances include the development of new sensors, improved data analysis methods, and the automation of measurement systems.
9.1. New Sensor Technologies
New sensor technologies, such as microfabricated sensors and thin-film sensors, have enabled more accurate and faster measurements of thermal conductivity. These sensors have smaller thermal mass and faster response times, allowing for more precise measurements of the temperature gradient and the heat flux.
9.2. Improved Data Analysis Methods
Improved data analysis methods, such as advanced curve-fitting algorithms and machine learning techniques, have enabled more accurate extraction of thermal conductivity values from the measured data. These methods can account for complex heat transfer effects and reduce the impact of noise and other errors.
9.3. Automation of Measurement Systems
The automation of measurement systems has improved the speed and efficiency of direct thermal conductivity measurement. Automated systems can control the temperature, apply the heat flux, measure the temperature gradient, and analyze the data, reducing the need for manual intervention and improving the reproducibility of the measurements.
10. The Role of COMPARE.EDU.VN in Thermal Conductivity Measurement Selection
COMPARE.EDU.VN plays a critical role in helping users navigate the complexities of thermal conductivity measurement. The website provides comprehensive comparisons of different measurement methods, equipment, and services, enabling users to make informed decisions based on their specific needs and requirements. COMPARE.EDU.VN offers detailed information on the advantages and disadvantages of each method, as well as guidance on selecting the appropriate technique for a given application.
10.1. Comprehensive Comparisons of Measurement Methods
COMPARE.EDU.VN offers comprehensive comparisons of different thermal conductivity measurement methods, including absolute and direct methods. The website provides detailed information on the principles of operation, advantages, limitations, and applications of each method, helping users to understand the strengths and weaknesses of each technique.
10.2. Comparisons of Measurement Equipment
COMPARE.EDU.VN provides comparisons of different thermal conductivity measurement equipment, including instruments from various manufacturers. The website offers detailed specifications, performance data, and user reviews, helping users to select the equipment that best meets their needs and budget.
10.3. Guidance on Method Selection
COMPARE.EDU.VN offers guidance on selecting the appropriate thermal conductivity measurement method for a given application. The website provides a decision tree that considers the type of material, the temperature range, the required accuracy, and the available budget, helping users to narrow down the options and select the most suitable method.
10.4. Expert Reviews and User Feedback
COMPARE.EDU.VN features expert reviews and user feedback on different thermal conductivity measurement methods and equipment. These reviews and feedback provide valuable insights into the real-world performance of the techniques and equipment, helping users to make informed decisions.
11. Case Studies: Direct Thermal Conductivity Measurement in Action
Several case studies illustrate the application of direct thermal conductivity measurement in various industries. These case studies highlight the benefits of using direct methods for characterizing the thermal properties of materials and optimizing the performance of engineered systems.
11.1. Case Study 1: Thermal Conductivity of Building Insulation Materials
In the construction industry, direct thermal conductivity measurement is used to characterize the thermal properties of building insulation materials. The Heat Flow Meter (HFM) method is commonly used to measure the thermal conductivity of insulation materials such as fiberglass, mineral wool, and foam boards. The measurements are used to ensure that the insulation materials meet specified thermal performance requirements and to optimize the design of energy-efficient buildings.
11.2. Case Study 2: Thermal Conductivity of Heat Sink Materials
In the electronics industry, direct thermal conductivity measurement is used to characterize the thermal properties of heat sink materials. The Transient Hot Strip (THS) method is commonly used to measure the thermal conductivity of heat sink materials such as aluminum, copper, and graphite. The measurements are used to optimize the design of heat sinks for electronic components and to prevent overheating.
11.3. Case Study 3: Thermal Conductivity of Automotive Engine Materials
In the automotive industry, direct thermal conductivity measurement is used to characterize the thermal properties of engine materials. The Guarded Comparative Longitudinal Heat Flow (GCLHF) method is commonly used to measure the thermal conductivity of engine materials such as aluminum alloys and cast iron. The measurements are used to optimize the design of engines and to improve their thermal efficiency.
12. Future Trends in Thermal Conductivity Measurement
The field of thermal conductivity measurement is constantly evolving, with new techniques and technologies being developed to improve the accuracy, speed, and versatility of the measurements. Future trends in thermal conductivity measurement include the development of non-contact methods, the use of machine learning for data analysis, and the integration of measurement systems with computer-aided design (CAD) tools.
12.1. Non-Contact Measurement Methods
Non-contact measurement methods, such as laser-based techniques and infrared thermography, are being developed to measure the thermal conductivity of materials without physically contacting the sample. These methods can be used to measure the thermal conductivity of delicate or hazardous materials, and they can be used to measure the thermal conductivity of materials at high temperatures.
12.2. Machine Learning for Data Analysis
Machine learning techniques are being used to improve the accuracy and efficiency of thermal conductivity measurement. Machine learning algorithms can be trained to analyze complex data sets and to extract thermal conductivity values with high precision. These algorithms can also be used to identify and correct for errors in the measurement process.
12.3. Integration with CAD Tools
The integration of thermal conductivity measurement systems with computer-aided design (CAD) tools is enabling engineers to incorporate thermal properties directly into their designs. This allows for more accurate simulations of thermal performance and enables the optimization of designs for specific applications.
13. Conclusion: Choosing the Right Method for Your Needs
In conclusion, direct thermal conductivity measurement is a valuable technique for characterizing the thermal properties of materials and optimizing the performance of engineered systems. While it offers numerous advantages, it is essential to understand the limitations of the method and to carefully consider the factors that can affect its accuracy. COMPARE.EDU.VN provides comprehensive resources and comparisons to help users navigate the complexities of thermal conductivity measurement and to select the right method for their specific needs.
The choice between absolute and direct methods hinges on the application’s specific requirements, considering factors such as the precision needed, resources available, and the nature of the materials. By understanding these nuances, you can select the most appropriate measurement technique, ensuring accurate and reliable results in your thermal conductivity studies.
Struggling to compare thermal conductivity measurement methods? Visit COMPARE.EDU.VN at 333 Comparison Plaza, Choice City, CA 90210, United States, or contact us via Whatsapp at +1 (626) 555-9090 for expert guidance and comprehensive comparisons. Let us help you make informed decisions and achieve accurate, reliable results in your thermal conductivity studies. Access COMPARE.EDU.VN today to make the right choice!
14. Frequently Asked Questions (FAQs)
Q1: What is thermal conductivity, and why is it important?
Thermal conductivity is a material’s ability to conduct heat. It’s crucial for designing efficient thermal management systems in various industries.
Q2: What are the main differences between absolute and direct (comparative) methods for measuring thermal conductivity?
Absolute methods don’t rely on reference materials, while direct methods compare a sample to a known standard. Absolute methods are generally more accurate but can be more complex.
Q3: What are some common direct methods for measuring thermal conductivity?
Common methods include the Transient Line Source (TLS), Transient Hot Wire (THW), Heat Flow Meter (HFM), and Guarded Comparative Longitudinal Heat Flow (GCLHF).
Q4: What factors can affect the accuracy of direct thermal conductivity measurements?
Factors include the accuracy of the reference material, contact resistance, heat flow uniformity, temperature control, and sample preparation.
Q5: What are some applications of direct thermal conductivity measurement?
Applications include materials science, engineering, quality control, and research in industries such as aerospace, automotive, construction, and electronics.
Q6: What are some recent advances in direct thermal conductivity measurement?
Recent advances include new sensor technologies, improved data analysis methods, and the automation of measurement systems.
Q7: How does COMPARE.EDU.VN help in selecting the right thermal conductivity measurement method?
COMPARE.EDU.VN provides comprehensive comparisons of different measurement methods, equipment, and services, enabling users to make informed decisions.
Q8: What is the role of reference materials in direct thermal conductivity measurements?
Reference materials with known thermal conductivity are used to compare the thermal response of a sample and determine its thermal conductivity. The accuracy of the reference material is crucial for the accuracy of the measurement.
Q9: Can direct methods be used for measuring the thermal conductivity of liquids?
Yes, methods like the Transient Hot Wire (THW) method are specifically designed for measuring the thermal conductivity of liquids.
Q10: Where can I find more information and comparisons of thermal conductivity measurement methods?
Visit compare.edu.vn for expert guidance and comprehensive comparisons of thermal conductivity measurement methods and equipment.
15. References
- ASTM International. (Various standards for thermal conductivity measurement).
- Incropera, F. P., & DeWitt, D. P. (2002). Fundamentals of Heat and Mass Transfer. John Wiley & Sons.
- Routledge. (2007). Thermophysical Properties of Matter: The TPRC Data Series.
