Energy-saving Applications Research Articles

Bird's nest inspired aerogels towards ultrahigh strength and robust flame retardancy at extreme environment

The mechanical properties of aerogels remain a critical concern for their application. Inspired from the hierarchical architecture of bird's nests, we have designed an effective biomimetic hybrid strategy for creating an aerogel with ultrahigh strength and robust flame retardancy. The super-molecular micro-to nanofibrils formed by boric acid and melamine act as “twigs” while a small part of biobased polysaccharide agar serves as “glue”. Via the water as the solvent and an eco-friendly freeze-drying method, the obtained boric acid-melamine/agar (BMA) aerogel with a low density (0.0760 g/cm3) exhibited exceptional high compressive strength, reaching up to 3.92 MPa at 80 % strain. A piece of the BMA aerogel with 10 cm2 can resist a motorcycle (150 kg) easily without any deformation. Additionally, the BMA aerogel demonstrated outstanding inherent flame retardant property (achieving UL-94 V-0 rating with relatively low the heat release, total heat release and CO release rate values) as well as superior thermal insulating properties (with a thermal conductivity as low as 0.0364 W/m⋅K). Given the distinctive mechanical properties and excellent other properties, the BMA aerogels hold great promise for potential promise in energy-saving and thermal protection applications. and the superior stiffness mechanism behind this performance is also analyzed.

Multiple scattering effect of spherical LaPO4 enhanced broadband emissivity for heat dissipation of electronic devices

High-performance infrared radiation materials with excellent broadband emissivity, remarkable thermal stability, and scalable fabrication processes play a vital role in heat dissipation and energy-saving applications. However, current strategies of broadband emissivity enhancement remain inadequate. This study investigates the impact of LaPO4 morphology on the infrared radiation properties of composite coating. Three distinct morphologies (sphere, rod and mesh sheet) of LaPO4 are explored using a simulation-aided method. The composite coating filled with large-sized spherical LaPO4 particles with low diffuse reflection, exhibits a significantly enhanced infrared radiation capability, resulting in a broadband emissivity of 95.6 %. Furthermore, the composite coating achieves a large temperature reduction of 6.2 °C and high cooling efficiency of 11.9 % when subjected to a heating power of 2250 W/m2. This work provides an innovative strategy for regulating material emissivity through morphology control, benefiting advancements low-cost radiation heat transfer technology.

The Effects of Polymerization on the Performance of Viologen-Based Electrochromic Devices.

In this work, electrochromic devices were prepared using the redox couple ethyl viologen diperchlorate and 1,1'-diethyl ferrocene in propylene carbonate as an aprotic solvent to facilitate ions separation and diffusion inside the devices. Electrochromic devices were made using electrochromic gel mixtures at the concentrations of 55%, 60% and 65% with respect to the bisphenol A polymer. In particular, two sets of gels were made: one set contained the bisphenol A not-polymerized while and the second one contained the polymerized polymer. Different techniques, such as cyclic voltammetry, UV-vis-NIR, and Raman spectroscopy, were used to study such systems to understand the differences in terms of performances between the different sets of electrochromic devices. Cyclic voltammetry confirmed that the oxidation process of the 1,1'-diethyl ferrocene and the reduction of the ethyl viologen diperchlorate occurred at about 0.4 V. Interesting variations in the transmittances were found between the two groups of samples. The best values of CE were provided by the electrochromic devices based on the polymerized electrochromic gel mixture at a concentration of 60% (EM60). The EM60 device result was CE = 92.82 C/cm2 in the visible region and CE = 80.38 C/cm2 in the near-infrared region, confirming that these devices can be used for energy-saving applications. A structural characterization of the materials used in the two sets of electrochromic devices was made using Raman spectroscopy, and the analysis supports the electrochemical models used to explain the processes involved during operation of the electrochromic systems.

Microencapsulated phase change material in 3D-printable mortars

The present study investigates the potential of replacing sand with microencapsulated phase change materials (MEPCM) in 3D-printable mortar to provide a promising way to improve thermal performance in 3D-printed buildings. Adding MEPCM significantly enhanced the rheological properties and early hardening evolution of cementitious mortar for 3D printing applications without the need for viscosity modifier agents. In hardened mortars, microstructural analysis and thermal cycling experiments confirmed that MEPCM remained intact and stable within the cementitious environment. The thermal properties of the treated mortars, including latent heat and thermal conductivity, were improved for energy-saving applications. Despite this, the compressive strength of the mortars dropped considerably by increasing the concentration of MEPCM while a strength of above 20 MPa was maintained. Simulation results from 3D Finite Element Method (FEM) and 1D reduced order model (ROM) closely matched the experimental data from printed walls in a thermal setup, validating the use of 1D ROM simulations for long-term predictions. In a case study, a printed wall where MEPCM replaced 80 % of the sand showed a ∼40 % reduction in energy consumption compared to mortar without MEPCM under real weather conditions.

Optimization of optical properties of nanocomposite films incorporating CWO and ITO nanoparticles for energy-saving window applications

Cesium tungsten oxide (CWO) and indium tin oxide (ITO) nanoparticles are potential candidates for application in energy-saving windows. However, most optical studies on these nanocomposite films lack systematic evaluation and design methods. In this work, the optical properties of spherical and cylindrical CWO and ITO nanoparticles under different geometric parameters based on the Lorenz–Mie and T-matrix theories are investigated, and spectral responses of CWO-PDMS and ITO-PDMS windows are calculated by solving the radiative transfer equation (RTE) using the Monte Carlo method. By evaluating and optimizing the geometric parameters of the nanocomposite films, energy-saving windows exhibit excellent optical performance, with a visible light transmittance that meets the indoor needs of the human eye (Tlum is about 0.6), and can shield most near-infrared light, especially CWO-PDMS windows (TNIR=0.04). Finally, a building energy consumption simulation analysis based on Energy Plus is conducted in three different cities: Jinan, Hong Kong, and Singapore. The results indicate that by adjusting the geometric parameters of nanoparticles, energy-saving windows can effectively reduce energy consumption in tropical and subtropical regions. This work provides guidance for the subsequent commercialization and experimental analysis of spectral selective composite films.

Developing a Design Guideline for a User-Friendly Home Energy-Saving Application That Aligns with User-Centered Design (UCD) Principles

Regarding issues with the majority of home energy-saving applications, the information is often too difficult for users to understand, and they struggle to comprehend communication via graphics or images displayed on the application’s screen. Furthermore, little is known about how users of home energy-saving applications behave. Therefore, this research aims to develop and evaluate a user-friendly design guideline for a home energy-saving application that applies four stages of User-Centered Design (UCD) processes. To identify significant issues and preliminary solutions, this research employed two rounds of co-creation activities involving nine experts and nine non-experts. Subsequently, an application prototype encompassing settings, about, home data, home assessment, and assessment summary was developed. The prototype underwent evaluation through an online questionnaire with 160 participants from four user groups, spanning expert and non-expert age groups. As a results from all four factors, the application received a mean score = 4.35 (good) from both non-experts and experts. This demonstrates that the prototype adopted with the guideline performed well in terms of User Experience, User Interface and User-Centered Design. This research provides developers and stakeholders with valuable guidelines to create applications or programs that are more efficient and user-friendly. This guideline is applicable to a wide range of sectors (eg, residential homes, workplaces, and educational institutions) and various domains (eg, Internet of Things (IoT), Home Energy Management Systems (HEMS), mobile applications, AI-Assisted in IoT-based Smart Microgrids). This would lead to the creation of applications that are easy for users to navigate and presentations that are impactful, ultimately helping to decrease energy usage and promote a more sustainable environment.

Investigation of dynamic start-up and thermal airflow characteristics for air-carrying energy heating and cooling system: Sidewall, ceiling, and composite walls

The dynamic start-up process of the air-carrying energy radiant system (ACERS) is crucial for operation control. The dynamic heat transfer process of sidewall, ceiling, and composite walls for air-carrying energy heating and cooling systems was investigated using field experiments and numerical simulation. A new dynamic start-up model was proposed to rapidly predict the dynamic response time and heat transfer surface temperature for controlling indoor temperature. Six schemes with different thermal flow characteristics resulting from temperature difference and velocity uniformity were quantitatively studied through numerical simulation, which helps determine their rationality. The results show that the dynamic start-up model aligns well with experimental data, with an error of less than 3 %. The fast response time of the air medium heat transfer surface for heating/cooling is short (less than 0.5 h). The ceiling provides better adjustability compared to the sidewall. In the unstable state (Gc < 0), the Gc-related buoyancy has a vertical promotion effect, leading to increased convection and decreased vertical temperature difference in the room. Adding the sidewall heating to the ceiling heating reduces the indoor vertical temperature difference by 23 % for the composite walls heating compared to the ceiling heating. Convection accounts for 27 % of the sidewall heating, which is 2.7 times higher than that of ceiling heating (11 %). Combining the dynamic start-up model with numerical analysis enables rapid prediction and analysis of the thermal performance of ACERS, which can be applied to advanced control and optimization for energy-saving applications.

Study on energy-saving applications of vacuum ejectors across various operational demands

Vacuum suction technology is a pivotal innovation within the Industry 4.0 revolution. Ejectors serve as the core of vacuum systems with distinct advantages such as simple structure, low cost, and ease of operation. However, traditional fixed ejectors suffer from low efficiency, energy waste, and poor adaptability. This study aims to optimize the design of vacuum ejectors to meet various requirements, achieving energy efficiency and high performance in automated production. On this basis, an energy-saving vacuum system based on dual ejectors is proposed, which can switch between single and dual ejectors depending on different working stages. When the vacuum reaches 90 kPa, the required motive pressure and the entrainment ratio are selected as the screening indicators for the vacuum ejector. A two-dimensional axisymmetric model is established and verified through experimentation. The key parameters are identified through a single-factor analysis. A multi-factor analysis is employed to determine the recommended values for each parameter and their respective applications. The energy-saving effects of the optimized ejectors are evaluated in conjunction with the automated processes. The findings indicate that the vacuum system based on dual ejectors can achieve rapid response and low air consumption. This paper contributes to advancing the research on energy-saving applications of ejectors.

Reversible thermochromic K2O·nSiO2-based anti-fire glass with bidirectional responsion and memory function

We describe a low-cost method for the synthesis of reversible thermochromic K2O·nSiO2-based anti-fire materials with bidirectional responsion and memory function, which was significant for energy-saving and fire-resistant applications. Here, the reversible thermochromic (RTC) and inverted reversible thermochromic (IRTC) K2O·nSiO2-based anti-fire glass were prepared via an in-situ reaction using a high solid content and low viscosity SiO2 sol (HSLV SiO2 sol, 55 wt%). The morphological, thermochromic, thermal insulation, and memory performances were systematically characterized. The pincer-like structure, rod-like structure and the layered microporous morphology were clearly shown in scanning electron microscopy (SEM) micrographs. The color change, foaming, and memory mechanisms were further investigated in detail. The significant differences appeared in the visible region of RTC and IRTC K2O·nSiO2-based anti-fire glass during heating and cooling process. FTIR spectra were used to characterize the difference among RTC, IRTC and control samples. The results indicated that a small amount of NH4+ caused the K2O·nSiO2-based anti-fire glass to exhibit IRTC characteristics, and the continuous addition of polyhydric alcohols was the key to obtain RTC performance. The IRTC K2O·nSiO2-based anti-fire glass was suitable for the conservatories or greenhouses, and the RTC K2O·nSiO2-based anti-fire glass reduced the direct sunlight exposure to control the indoor temperature. Combined with morphological and Tg analysis, the thermal insulation performance was enhanced by a microporous insulating layer with a sponge-like structure. We also used the bidirectional reversible thermochromic performance to prepare a novel anti-fire glass component for construction with anti-counterfeiting function. This work provided a new approach for the application of multifunctional smart windows.

A Modified VIRT with Planar Transformer for Energy-Saving Applications

A Modified VIRT with Planar Transformer for Energy-Saving Applications

Conjugated Microporous Polymer Aerogels Encapsulated within Hydroxyapatite Nanowires Exhibit Good Thermal Insulation and Flame-Retardant Properties.

Aerogels have been widely studied in the field of thermal insulation. Herein, we reported a kind of conjugated micropolymer (CMP) aerogel synthesized by 1,3,5-triethynylbenzene and 2-amino-3,5-dibromopyridine. To enhance the flame-retardant property, we composited hydroxyapatite (HAP) nanowires with a CMP aerogel. Transmission electron microscopy (TEM) analysis revealed that HAP nanowires were encapsulated within nanosized CMP tubes. In addition, the thermal conductivity of HAP2-NCMP aerogel was 0.0251 W m-1 K-1, which possesses good thermal insulation property. In the micro-combustion calorimeter (MCC) test, compared with pure NCMP, the peak heat release rate (pHRR) of HAP2-NCMP decreased from 39.3 to 30.82 W g-1, approximately 21.6% lower. Furthermore, with the increased addition of hydroxyapatite in the HAP-NCMP composite, the pHRR of HAP3-NCMP decreased by about 37.4%. Besides, NCMP possesses good mechanical properties, with a compressive strength of 117.3 kPa at a strain level of 60%. These findings suggest promising application potential for HAP-NCMP in energy-saving and flame-retardant applications.

Ag decorated V2O5 electrodes as a promising option for electrochromic, photovoltaic, and energy-saving applications

This study reports the fabrication of electrochromic Ag decorated V2O5 thin film by thermal evaporation method at 10−5 torr vacuum medium and the effects of the Ag doping to the V2O5 matrix. Besides, the electrochromic capabilities and energy-saving characteristics of the films are also in the scope of this study. Structural and morphological properties are investigated by XRD, FESEM, and AFM. The films have a polycrystalline structure and a porous surface. FTIR and Raman spectra verify the molecular formation of the films. The performance of the electrochromic films is characterized by a variety of techniques such as cyclic voltammetry, chronoamperometry, chronocolumetry, and electrochemical impedance spectroscopy. The color of the films changes from yellow to green and then from green to blue in the range of −1.2 and + 1.0 V vs Ag/AgCl with a reversibility of 92.9 %. With the response times of tb = 13.6 s and tc = 9.4 s, an optical modulation of 51.7 % (from yellow to blue), and a coloration efficiency of 93.7 cm2 C−1, Ag:V2O5 becomes an impressive electrochromic material produced by physical methods. Linear sweep voltammetry studies show that the photocurrent of both V2O5/ITO and Ag:V2O5/ITO electrodes increases under solar illumination. The supercapacitive performance of the film is investigated by cyclic voltammetry, and Ag:V2O5 is an encouraging electrode material with a specific capacitance of 720.9 F g−1 at 5 mV s−1 scan rate. An equivalent circuit is fitted from the film Nyquist data and the results also confirm the positive contribution of Ag doping on the response times, energy saving, and photoresponse of V2O5 thin film. In this regard, the produced electrodes are highly promising for potential applications in electrochromic, energy storage, and photovoltaic devices.

Mechanical, wear and thermal properties of natural fiber-reinforced epoxy composite: cotton, sisal, coir and wool fibers

Natural fiber-reinforced epoxy composites (NFRCs) have gained significant attention in recent years due to their potential as environmentally friendly and sustainable materials. These composites combine natural fibers, derived from plants, with epoxy resins to create a material with enhanced properties. The objective of this study is to investigate the mechanical, wear and thermal properties of NFRCs incorporating cotton, sisal, coir and wool fibers. The vacuum-assisted resin transfer molding (VARTM) technique was employed to produce composite plates, followed by conducting tests on tensile, wear and thermal properties. The cotton composite showcased the highest tensile strength, reaching 52.81 MPa, while the coir composite exhibited the lowest, measuring 15.34 MPa. Sisal composite exhibited a moderate wear rate (1.423 mm3/Nm) and a lower coefficient of friction (0.233), implying smoother relative motion. Coir composite presented the highest wear rate (4.615 mm3/Nm), attributed to its coarse fiber nature. Thermal conductivity is highest at cotton composite (1.017 W/mK) and is lowest at coir composite (0.187 W/mK). Additionally, the highest specific heat was observed in the coir composite (26.313 MJ/m3K). Cotton demonstrated potential for efficient heat transfer, while wool outperformed in insulation. Sisal displayed versatility for structural applications. Coir emerged as an effective insulator with energy-saving applications.

Light-Field Optimization of Deep-Ultraviolet LED Modules for Efficient Microbial Inactivation

Public awareness of preventing pathogenic microorganisms has significantly increased. Among numerous microbial prevention methods, the deep-ultraviolet (DUV) disinfection technology has received wide attention by using the nitride-based light-emitting diode (LED). However, the light extraction efficiency of DUV LEDs and the utilization rate of emitted DUV light are relatively low at the current stage. In this study, a light distribution design (referred to as the reflective system) was explored to enhance the utilization of emitted DUV from LEDs, leading to successful and efficient surface and air disinfection. Optical power measurements and microbial inactivation tests demonstrated an approximately 79% improvement in average radiation power density achieved by the reflective system when measured at a 5 cm distance from the irradiation surface. Moreover, a statistically significant enhancement in local surface disinfection was observed with low electric power consumption. The reflective system was integrated into an air purifier and underwent air disinfection testing, effectively disinfecting a 3 m3 space within ten minutes. Additionally, a fluorine resin film at the nanolevel was developed to protect the light module from oxidation, validated through a 1200 h accelerated aging test under humid conditions. This research offers valuable guidance for efficient and energy-saving DUV disinfection applications.

Annual Energy-Saving Smart Windows with Actively Controllable Passive Radiative Cooling and Multimode Heating Regulation.

Smart windows with radiative heat management capability using the sun and outer space as zero-energy thermodynamic resources have gained prominence, demonstrating a minimum carbon footprint. However, realizing on-demand thermal management throughout all seasons while reducing fossil energy consumption remains a formidable challenge. Herein, an energy-efficient smart window that enables actively tunable passive radiative cooling (PRC) and multimode heating regulation is demonstrated by integrating the emission-enhanced polymer-dispersed liquid crystal (SiO2@PRC PDLC) film and a low-emission layer deposited with carbon nanotubes. Specifically, this device can achieve a temperature close to the chamber interior ambient under solar irradiance of 700W m-2, as well as a temperature drop of 2.3°C at sunlight of 500W m-2, whose multistage PRC efficiency can be rapidly adjusted by a moderate voltage. Meanwhile, synchronous cooperation of passive radiative heating (PRH), solar heating (SH), and electric heating (EH) endows this smart window with the capability to handle complicated heating situations during cold weather. Energy simulation reveals the substantial superiority of this device in energy savings compared with single-layer SiO2@PRC PDLC, normal glass, and commercial low-E glass when applied in different climate zones. This work provides a feasible pathway for year-round thermal management, presenting a huge potential in energy-saving applications.

Sustainable, low-cost, high-contrast electrochromic displays via host–guest interactions

Electrochromic (EC) displays with electronically regulating the transmittance of solar radiation offer the opportunity to increase the energy efficiency of the building and electronic products and improve the comfort and lifestyle of people. Despite the unique merit and vast application potential of EC technologies, long-awaited EC windows and related visual content displays have not been fully commercialized due to unsatisfactory production cost, durability, color, and complex fabrication processes. Here we develop a unique EC strategy and system based on the natural host and guest interactions to address the above issues. A completely reusable and sustainable EC device has been fabricated with potential advantages of extremely low cost, ideal user-/environment friendly property, and excellent optical modulation, which is benefited from the extracted biomass EC materials and reusable transparent electrodes involved in the system. The as-prepared EC window and nonemissive transparent display also show comprehensively excellent properties: high transmittance change (>85%), broad spectra modulation covering Ultraviolet (UV), Visible (Vis) to Infrared (IR) ranges, high durability (no attenuation under UV radiation for more than 1.5 mo), low open voltage (0.9 V), excellent reusability (>1,200 cycles) of the device's key components and reversibility (>4,000 cycles) with a large transmittance change, and pleasant multicolor. It is anticipated that unconventional exploration and design principles of dynamic host-guest interactions can provide unique insight into different energy-saving and sustainable optoelectronic applications.

Ferroelectric heterostructure nanocomposites based on Bi2MoO6 nanosheets and Bi2S3 nanorods for rapid piezocatalysis of organic dyes and antibiotics

Among numerous polluting compounds, the organic dyes and antibiotics are two servious factors causing water pollution. Hence, it is urgent to find a fast and safe way to degrade waste water in a sustainable approach. Here, ferroelectric heterostructure based on 2D Bi2MoO6 nanosheets and Bi2S3 nanorods has been prepared by a two-step solvothermal method for the reduction of organic dyes and antibiotics. Due to the energy band balance between Bi2S3 and Bi2MoO6, the formed type-II heterostructure can populate charge transfer at the junction and effectively inhibit electron-hole recombination. Under ultrasonic stimulation, catalytic active sites of a Bi2MoO6/Bi2S3 heterostructure for pollutant degradation can be generated through rapid charge transfer activation, thus enhancing the catalytic degradation effect of organic dyes and antibiotics. The Bi2MoO6/Bi2S3 heterostructure not only has good degradation effect, but also shows better stability. This work opens up new avenues for designing highly-efficient catalysts, which is of importance for wastewater degradation and energy-saving applications.

Simulations and experimental studies of thermochromic performances of multilayered VO2 nanocone array for energy-saving smart window applications

In this work, VO2 parabolic nanocone array (PNA) was studied. Using the idealized geometry of truncated nanocone array (TNA), simulations demonstrated that VO2 TNA with the low and graded effective refractive index could greatly increase the luminous transmittance (Tlum) compared to VO2 film. Meanwhile, isolated VO2 nanocones with rutile phase could improve the solar modulation (ΔTsol) due to LSPR-enhanced absorption. Experimentally, the single-layered VO2 PNA, fabricated by annealing as-deposited V films with thicknesses of 6, 9 and 12 nm, exhibited ultrahigh Tlum, and multilayered VO2 PNAs were fabricated to improve ΔTsol with slight decrease in Tlum. For film thickness of 6 nm, ΔTsol of multilayered VO2 PNA could be improved from 4.9 % to 23.1 % by adding the layer number from one to eight, while Tlum decreased from 96.6 % to 75.8 %. For film thickness of 9 nm, three-layered VO2 PNA showed the optimum performances of ΔTsol = 16.5 % and Tlum = 78.2 %. By manipulating the size, porosity and layer number of VO2 PNA, thermochromic performances were tunable to achieve the requirements for smart window applications (ΔTsol > 10 % and Tlum > 60 %). In addition, multilayered VO2 PNA displayed the suitable pale-yellow color for actual applications. Thus, multilayered VO2 PNA could be a potential nanostructure for energy-saving smart window applications.

Transparent ultrahigh-molecular-weight polyethylene/MXene films with efficient UV-absorption for thermal management

The rational use and conversion of energy are the primary means for achieving the goal of carbon neutrality. MXenes can be used for photothermal conversion, but their opaque appearance limits wider applications. Herein, we successfully develop visible-light transparent and UV-absorbing polymer composite film by solution blending the MXene with polyethylene and then vacuum pressing. The resulting film could be quickly heated to 65 °C under 400 mW cm−2 light irradiation and maintained over 85% visible-light transmittance as well as low haze (<12%). The findings of the indoor heat insulation test demonstrate that the temperature of the glass house model covered by this film was 6-7 °C lower than that of the uncovered model, revealing the potential of transparent film in energy-saving applications. In order to mimic the energy-saving condition of the building in various climates, a typical building model with this film as the outer layer of the window was created using the EnergyPlus building energy consumption software. According to predictions, they could reduce yearly refrigeration energy used by 31-61 MJ m−2, and 3%-12% of the total energy used for refrigeration in such structures. This work imply that the film has wide potential for use as transparent devices in energy-related applications.

Transient simulation and experimental analysis for the response of dual-cycle air-carrying energy radiant diffuse terminal

A novel air-carrying energy radiant diffuse terminal is proposed, and the response of the terminal is investigated by field experiment and numerical simulation. This paper explores the dynamic operation characteristics of the new system to guide the optimal operation of the system. A transient simulation method of three factors (conduction, convection, and radiation) with dual-circulation (air-carrying energy zone and occupied zone) is put forward for the radiant diffuse terminal with a fresh air system. This transient simulation sets up the porous baffle model coupling radiation model concurrently, revealing the dynamic thermal performance for the system's response accurately, quickly, and comprehensively. This method avoids the limits for the complexity of mini porous (Pore size of 1 mm–3mm) geometric models and the transient uncertainty in multiple combination models. The results show that the average error between the convective-conductive model and the convective-conductive-radiative model is about 8% at five different heights. This system has high response performance, which can quickly heat the room while maintaining the comfort requirements of vertical temperature. The radiated heat transfer between the radiant diffuse terminal and the occupied zone is greater than the convective heat transfer (Radiation accounts for 74%). This system has a short response time, high energy efficiency, uniform airflow, and eliminates draught rating. Moreover, the indoor non-uniform transient thermal and humid environments, the thermal comfort, and air quality for the response of the terminal with fresh air system under four different diffuser placements are compared using computational fluid dynamic simulation. The results indicate that introducing heating strategies featuring higher-positioned fresh air inlet and lower-positioned recirculation return air outlet for this system leads to a temperature efficiency increase by 5%, velocity uniformity by 8%, and age of air reduction by 16–50% in human-breathed zone and the response time by 25%, which shows substantial potential for energy savings. The transient simulation and experiments in the paper are beneficial to optimize design parameters and carry out energy-saving applications of operation energy consumption for the response of this terminal with a fresh air system in the future.