1 Introduction

About 68% of the world’s population will live in cities by 2050 (Blanco et al., 2021). The world faces serious challenges due to the age of urban development. Results show that urbanization makes a positive contribution to emissions and environmental pollution. There are many attempts and methods for sustainability to balance the environment with development (Abbas et al., 2024; Abbas, Mamirkulova, Abbas et al., 2024a, b; Al-Sulaiti et al., 2023; Balsalobre-Lorente et al., 2023; Li et al., 2024; Tan et al., 2024; Wang et al., 2023). The built environment must be sustainable and resilient to adapt and respond to the surrounding conditions and ensure the comfort of its residents (Hayter, 2005; Palusci & Cecere, 2022). Designers should think long-term When designing and planning a city (SALVADOR, 2014). One of the most essential elements of the formation of cities is urban residential districts (URDs). Two factors affect URDs: natural factors, which are humidity, wind, and temperatures, and the human factor, which is the spatial form (Lu et al., 2022). There is no priority to mitigate the impact of harsh summer conditions, which negatively affect the internal cooling requirements of buildings and outdoor thermal comfort (Galal et al., 2020). The climatic factors of the city and the application of NV must be considered during urban planning to achieve sustainable design (Gülten & Öztop, 2020; Sayfutdinova, 2020; Shalaby et al., 2018).

A study proved that certain spatial forms in the design of URDs lead to fundamental differences in the ventilation capacity and improve ventilation to an adequate degree (Lu et al., 2022). Therefore, wind-sensitive urban design (WiSUD) is critical to leveraging wind and its benefits in cities. Ventilation efficiency is associated with urban forms and urban tissues, so they have a strong correlation with wind conditions, so urban design and planning must consider the impact of wind on air quality and the thermal environment (Çamaş & Aydın, 2022; Guo et al., 2017; Liu et al., 2022; Mirhosseini, 2019). The urban wind corridor is a factor that helps to reduce the air temperature in urban areas (Son et al., 2022; Yu et al., 2022). The comfort level of the users in the buildings increases when the speed of the outside air is suitable, so the volume and pattern of outdoor airspeeds should be monitored at different levels (Dash & Chakraborty, 2020; Tang et al., 2012). The performance of NV can be increased by taking some planning and architectural decisions such as expanding a road adjacent to a building or modifying canyon geometries, or removing high-rise buildings, ventilation channels, open space, and reasonable layout of the distribution of buildings (Guo et al., 2017; Sayfutdinova, 2020; Song et al., 2021).

The wind causes pressure loads affected by several elements, including the geometry of neighborhoods or buildings and the flow conditions. The pressure distribution on the downstream object varies according to the distance between the buildings (Gnatowska, 2019). Wind pressures affect NV systems and cause changes (Kuznetsov et al., 2016). The pressure difference, even if it is a small pressure difference, represents a natural driving force sufficient to allow NV. The urban environment affects the pressure differences between the facades and the airflow direction (Ramalho Fontenelle et al., 2015). Local urban morphological changes can adjust wind flow patterns of pressure, velocity, and building ventilation rate (Lee & Mak, 2022; Song et al., 2021).

Urban ventilation is the introduction of fresh air into urban tissues to reduce temperatures, thus improving indoor and outdoor thermal comfort (Heusinger & Sailor, 2019; Palusci & Cecere, 2022). It has been proven that human thermal sensation is affected by different meteorological factors in different seasons of the year (Wei et al., 2022). Thermal comfort assessment is based on the thermal balance of the human body with constant environmental conditions in changing outdoor environments due to urban morphology (Hwang et al., 2022). There are some researches define thermal comfort as a state of mind of human that expresses satisfaction with the thermal surroundings (Nikolopoulou, 2011). The Universal Thermal Climate Index (UTCI) assesses the outdoor thermal environment, which indicates that it becomes universally applicable to different climates (Lam & Lau, 2018).

During the planning stage, the wind potential at the construction site should be analyzed to improve indoor air quality, reduce summer temperatures, increase the efficiency of NV, and reduce energy demand. Energy efficiency in buildings and indoor air quality can be improved using NV (Sayfutdinova, 2020; Song et al., 2021; Yang et al., 2021). On an urban scale, the urban form has been found to have an essential role in regulating the energy performance of buildings in residential areas that are located in complex climatic conditions (Bouyer et al., 2011; Çamaş & Aydın, 2022; Ko & Radke, 2014; Mutani et al., 2022; Shang, 2022). Improving the thermal performance of outdoor spaces reduces the demand for cooling energy inside the buildings (Mahmoud & Ragab, 2020). By improving urban ventilation, energy demand can be reduced by 6.704% in urban areas (Yang et al., 2021).

Aerodynamics is influenced by the shape and formation of urban areas, which depend on many things, including the mutual arrangements between buildings (Palusci & Cecere, 2022). So, it is necessary to consider the arrangement of buildings in urban planning (Ng et al., 2011). Through the optimal arrangement of the streets/buildings, the demand for building energy can be reduced, and a better thermal environment can be created (Yang et al., 2021). Some factors affect the environmental wind conditions and their distribution in an urban environment: the arrangement of building arrays, building shapes, and Incident wind angles. Arranging the building arrays to take advantage of wind flow helps create sustainable and livable urban life (Lee & Mak, 2021).

Rapid urbanization and population growth pose challenges in new cities. Planning and designing new cities require careful consideration of factors such as environmental sustainability. Promoting sustainable practices in new cities is crucial for creating a healthy and livable environment. As urban expansion continues globally and more people migrate to cities, understanding the key trends of urbanization and implementing strategies to make cities more resilient, inclusive, and sustainable is essential (Wankhade et al., 2023).

There is a need for further research to develop new cities, considering different climates and locations to improve ventilation strategies. Expanding the case study collection to include cities in various climates would provide an overview of typical conditions and effective methods in urban planning. Studies have focused on standards such as air velocity and temperature to understand and improve air displacement and the potential for natural ventilation in both indoor and outdoor environments. Analyzing urban ventilation and air displacement can provide insights and applicable strategies for various climatic conditions, including hot and humid subtropical climates, when planning and designing new cities (Wankhade et al., 2023). There are many examples for new sustainable cities worldwide that consider climatic conditions before planning to reduce energy consumption like Masdar City in United Arab Emirates, The Line city in Saudi Arabia, and Skolkovo village (Moscow area) (Abdulmaksoud & Beheiry, 2023; Al-Sayed et al., 2022; Bechu & Bechu, 2019; Chayaamor-Heil, 2023; Chayaamor-Heil & Vitalis, 2021; Coskun, 2023; Steven Griffiths, 2020).

Our research focuses on a case study within the New Aswan city, located in the desert and facing extreme temperature rises, necessitating the rearrangement of buildings in URDs. This case study contributes to improving future sustainable planning in New Aswan, resulting in positive enhancements to natural ventilation, improvement in UTCI, and a reduction in energy consumption. Implementing and generalizing the findings and strategies from this case study are crucial for planning and designing various URDs in new cities of different regions worldwide, especially in hot areas experiencing high temperatures, desert regions, urban areas with poor ventilation, or those with high energy consumption. Our case study is vital for the widespread application of the results and strategies of the case study to address the challenges of climatic conditions in hot-arid during planning sustainable and environmentally friendly URDs in new cities in different regions worldwide not only in Egypt.

1.1 Problem statement

The problem lies in the need for more attention to outdoor and indoor thermal comfort during urban residential districts (URDs) planning in the new cities in Egypt, especially in New Aswan.

1.2 Research methodology

A careful consideration of urban development is essential for creating sustainable URDs to avoid poor planning decisions that negatively impact URDs. So, there are financial investments in energy, addressing climate change and promoting sustainability to reduce energy consumption therefore mitigating environmental impacts (Hussain et al., 2021; Iorember et al., 2023; Li et al., 2022; Zhuang et al., 2022).

The next part is the answer to the research question of how improve the outdoor and indoor thermal comfort to save energy in URDs planning it was chosen a social housing area in Egypt, New Aswan, to carry out the study on it. This study aims to reach the sustainable form of URDs in New Aswan through biomimicry to improve outdoor thermal comfort by reducing UTCI values and thus reducing energy consumption. The form and process of the prairie dog’s burrow were applied to URDs form to see the result, even if the differences were slight. The simulation was carried out through four phases in this study, air pressure, wind speed, UTCI values, and energy consumption. Our study took a duration in the range of one year and half. The framework of this research is shown in (Fig. 1).

Fig. 1
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Research framework

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2 Challenges facing urban residential districts (URDs) in Egypt

URDs worldwide face various challenges in terms of living conditions. These challenges include inadequate housing, security risks, low building standards, incomplete supporting facilities, poor living environments, and inadequate public services. To address these challenges, different approaches have been explored in literature. One approach involves improving outdoor thermal comfort and local climate conditions through urban design and planning, considering environmental and human standards (Aghamolaei et al., 2023; Allal et al., 2023). There is a need to understand the relationship between outdoor thermal comfort and energy use intensity in various urban block designs. There is a shortage of research on the impact of external urban space design variables on the thermal comfort efficiency of interior spaces, and there is a knowledge gap in understanding how different urban patterns and configurations affect outdoor thermal comfort (Abbas & Eldin, 2023; Heshmat Mohajer et al., 2022; Khraiwesh & Genovese, 2023). Therefore, in our research, we attempted to bridge this knowledge gap and demonstrate the extent to which URDs configuration affects both outdoor and indoor thermal comfort, subsequently influencing energy consumption.

The continuous migration from the countryside to the Egyptian cities and the increase in the population were accompanied by a similar expansion in the urban fabric (Shalaby et al., 2018). The Egyptian government is implementing social housing projects for people with limited income in new cities (Mahmoud & Ragab, 2020). There is an ignoring of the design of a comfortable thermal environment in planning new urban communities in Upper Egypt (Galal et al., 2020). Based on the Egyptian Electricity Holding Company 2020/2021 annual report, the highest sector of electrical energy consumption inside Egypt is the residential sector, with a rate of 40.5%. There is an increase in the electrical consumption of the residential field compared to the rest of the fields due to the continuation of the urban expansion and thus to the increased use of air conditioning devices due to the high temperatures during the summer (Arab Republic of Egypt, 2021). However, the Egyptian government has already begun to focus on the establishment of sustainable cities prioritizing thermal comfort and aiming to reduce energy consumption in the new cities in Egypt (Sayed Hassan Abdallah & Mohamed Ahmed Mahmoud, 2022). As a result, the Egyptian government has built and development 14 new sustainable cities all across Egypt (Hussein & Pollock, 2019; Nasr et al., 2023).

In cities, the construction sector is the largest energy consumer (Changalvaiee et al., 2017). By 2080, cooling energy consumption will increase by 39%, which means that existing air conditioning and ventilation systems will be less large (Abdollah et al., 2021). Urban structures affect the ventilation potential, energy loads of buildings, and the urban microclimate (Merlier et al., 2018). Urban design patterns influence thermal comfort and microclimate (Yahia et al., 2018). Various modern forms of urban patterns have been designed and built without considering the climatic context. Therefore, the urban design principle is thermal adaptation because it provides a suitable climate during the hot seasons (Matallah et al., 2021). The lack of thermal comfort due to the high temperatures in the hot seasons causes discomfort and inconvenience to the residents. In urban planning, designers need more regard for thermal comfort (Yahia & Johansson, 2014). Thermal adaptation has different strategies, including shading, natural ventilation, natural lighting, and building materials (Matallah et al., 2021).

2.1 Urban residential districts (URDs) in New Aswan

New Aswan established through a presidential decree (96/1999) on an initial area of 3900 acres, later expanded to 18490.92 acres by a cabinet decree (807/2015), this city is situated on the west bank of the river Nile, approximately 12 km away from Aswan city. It is an Egyptian city 700 km to the south of Cairo, 12 km from the city of Aswan. The total area of the city spans 22390.9 thousand acres, with 3.3 thousand acres designated for urban community purposes. Under the housing sector it has successfully implemented 280 developed housing units, while the Ebny Baitak project has seen the completion of 2886 housing units out of a total of 3530 plots in the city. The progress includes the implementation of 2600 units, completion and finishing of 1420 units, and the initiation of 1860 units for social housing. The city comprises a total of 1735 plots for housing, categorized as socio-economic, medium, villas, special, and home houses, with an additional 1447 pieces for the National project (Ebny Baitak). The population target for the city is set at 850 thousand inhabitants in the year 2023 (Authority; Galal et al., 2020).

It has several housing types, including social housing (Galal et al., 2020). A vital design tool begins by exploring the ecosystem of a specific site, such as a site that may suffer from excessive cooling, heating, or severe weather (Peters, 2011). Aswan is one region that suffers from high temperatures exceeding 40 °C, as shown in (Fig. 2). The conclusion from (Fig. 2) is that temperatures rise and exceed 40 °C during the six summer months, from April to September, specifically from 12 pm to 6 pm. For more accuracy, the maximum temperatures during the middle six months of the year 2021 on certain days at certain hours are shown in (Fig. 3(Project, 2022 ).

Fig. 2
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A map showing the temperatures during the year 2021 for Aswan

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Fig. 3
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Max temperature for the middle six months of the year 2021 on certain days at certain hours (Project, 2022)

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3 Biomimicry and sustainable built environment

Human needs and design problems have thoughtful solutions through biomimicry (Jamei & Vrcelj, 2021). The approach of biomimicry is an innovative approach that helps solve human problems by studying natural designs and systems (Benyus, 1997; Ferwati et al., 2019; Jamei & Vrcelj, 2021; Radwan & Osama, 2016; Reed, 2004). There are three levels of biomimicry: behavior level, ecosystem level, and organism level. The level of behavior is the simulation of the behavior of the living being. The ecosystem is the level that simulates the ecosystem and the principles that allow it to operate efficiently and successfully. The living being is the simulation of the living being as a whole or part of it (Hu, 2017; Jalil & Kahachi, 2019; Khoshtinat, 2015). The design process in biomimicry has two main approaches: the solution-based approach (bottom-up) and the problem-based approach (top-down) (Radwan & Osama, 2016). In recent years, the application of biomimicry has expanded into various areas, including architectural design and urban design (Khoshtinat, 2015; Uchiyama et al., 2020). Biology and architecture do not have the same status on the scientific map, and the distance between them is far or invisible at first sight (Chayaamor-Heil & Vitalis, 2021). A significant challenge is facilitating knowledge transfer from ecological and biological disciplines to practices of urban design and architecture (Blanco et al., 2021). Efforts can be positioned and developed around a shared vision of future sustainable cities for up to 25, 30, or 50 years from now through biomimicry (Dicks et al., 2021; Taylor Buck, 2017; Uchiyama et al., 2020). Specific objectives exist when applying the biomimicry approach in projects (planning and design), such as indoor and outdoor air quality, thermal comfort, and adaptation to climate change to achieve sustainability (Blanco et al., 2021).

3.1 Biomimetic studies

Architects were asked to design a set of houses in a very cold place for researchers and their families in District 11, Skolkovo village (Moscow area), architects Bechu. Architect Pablo Lorenzino was interested in emperor penguins as a role model for urban design and architecture in a cold climate (Chayaamor-Heil & Vitalis, 2021). The key to survival for emperor penguins in the Antarctic during winter is to assemble, and individual movements become impossible (Gerum et al., 2013; Zitterbart et al., 2011). So, the initial idea was inspired by the social organization of the emperor penguins and was to arrange numbers of housing in the form of a circle. Pablo used a calculation algorithm to transfer the principle of thermal regulation to an urban complex that can protect one hundred individual houses from extreme cold wind during winter and gain 5 °C above the outdoor temperature. As a result, heating energy consumption is reduced (Bechu & Bechu, 2019; Chayaamor-Heil, 2023; Chayaamor-Heil & Vitalis, 2021).

3.2 Integration of biomimicry in the design of urban residential districts (URDs) in New Aswan

There are different and alternative methods of biomimicry in urban design to overcome different problems such as high temperatures and energy consumption. There are modern methods such as artificial intelligence (AI) technologies and traditional methods based on the use of mathematical models, statistical analysis, and expert opinions (Tan et al., 2023). Studies have shown that the biomimicry approach offers unique advantages compared to alternative methods in achieving optimal planning and sustainability. This involves integrating nature with the built environment, enhancing energy efficiency, and transforming urban environments into healthier and more climate-resilient spaces that cater to the needs of citizens (Martino, 2023; McGregor & Cowdy, 2023; Rehan, 2023; Tan et al., 2023; Verbrugghe et al., 2023). Therefore, in this research, we have decided to use biomimicry approach in the planning of URDs.

Because of the hot climate in New Aswan, it was necessary to modify the URDs form to achieve indoor and outdoor thermal comfort. Therefore, solutions have been sought in nature. The prairie dog’s burrow was the closest solution to modifying the URDs form. The prairie dog makes the burrow so that the entrance and exit are at different heights, which causes a pressure difference and achieves good ventilation inside the burrow, as shown in (Fig. 4) (Paar & Petutschnigg, 2016).

Fig. 4
figure 4

Air circulation in the burrow of prairie dog (Paar & Petutschnigg, 2016)

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The prairie dog’s burrow is 10 to 30 m long and 1 to 5 m deep, as shown in (Fig. 5) (Vogel et al., 1973).

Fig. 5
figure 5

Dimensions of prairie-dog’s burrow

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The proportion was taken from the largest dimensions, 30 m long and 5 m deep, as the following equation:

$${{\rm{D}} \over {\rm{L}}}\, = \,{5 \over {30}}$$
(1)

4 Case study domain

The study area is in Egypt, Aswan Governorate, New Aswan; its latitude is 24°11’49.16"N, and its longitude is 32°50’31.32"E. The location is 0.20 KM north of NBE ATM - New Aswan Branch 2, as shown in (Fig. 6). The study area is a hybrid social housing area between parallel and enclosed and contains 12 buildings. No buildings around the study domain were considered.

Fig. 6
figure 6

Domain case study location in New Aswan

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4.1 Scenarios of urban residential districts (URDs) analysis

The domain of study contains 12 social housing buildings, each building has five floors, the height of each floor is 3 m, and thus the height of the building is 15 m. The study in this research contains three different scenarios. The first scenario is the current situation without changing the arrangement or orientation of the buildings (scenario A).

The second and third scenarios are to rearrange the buildings based on the prairie dog’s burrow proportions. So, the problem and, at the same time, the challenge was that the prairie dog’s burrow is dug underground vertically, and it is a tube closed on all sides, which allows for achieving a pressure difference and good ventilation inside the tube. However, the study in this research is about modifying URDs form on a horizontal level, making a wind corridor between each building and the other, to achieve pressure differences and NV between buildings through the idea and form of the prairie-dog’s burrow. By considering the length and width of the building of social housing is 26.44 m, and 15.85 m, respectively, and the ratios and dimensions resulting from Eq. (1) to form a new form for the URDs, are shown in (Fig. 7) and the following equation:

$${{{\rm{26}}{\rm{.44}}} \over {\rm{L}}}\, = \,{5 \over {30}}$$
(2)

L = 158.64m

The distance between building became 11.9m

Fig. 7
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Proportions to form new scenarios of URD

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According to Eq. (2), the new proportion to arrange the twelve buildings to form a new URD is shown in (Fig. 8) and the following equation:

$${{\rm{D}} \over {\rm{L}}}\, = \,{{70} \over {214.15}}$$
(3)
Fig. 8
figure 8

The new form of URD and its dimensions

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To apply these new ratios to rearrange buildings based on prairie-dog’s burrow in any other area worldwide, Eqs. (1), (2), and (3) can be followed to derive the following equation:

$${{\rm{H}} \over {\rm{W}}}\, = \,{{15} \over {12}}\, = \,{5 \over 4}$$
(4)

H is the height of the building; W is the distance between each building and the other.

The buildings were migrated from each other to achieve the pressure difference and thus achieve good ventilation between the buildings. The second scenario is the new form of URD, and its orientation is North-South (scenario B). The third scenario is also the new form of URD, but its orientation is East-West (scenario C). (Fig. 9) shows scenarios A, B, and C.

Fig. 9
figure 9

(a) Current situation of URD (scenario A), (b) new form of URD (North-South) (scenario B), (c) new form of URD (East-West) (scenario C)

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4.2 Simulation procedure

Two simulation programs were used in this research. Autodesk CFD (version 2023) was used for pressure and wind movement simulation and required the model to be surrounded by a wind tunnel. The dimensions of the wind tunnel for each scenario were as follows: First, the height is H + 5 H, the outlet is 15 H, and the inlet and the rest of the sides are 5 H, as shown in (Fig. 10). H refers to the height of the buildings. The wind speed was also entered as 5.64 m/s and its direction from north.

For the simulation of UTCI values outdoor and energy consumption inside buildings at the level of the URD, we used Rhino7 software and Grasshopper is a complementary addition that can enhance the design and simulation capabilities of Rhino, so we used it because of the plugins in it, like Ladybug, Honeybee, and Dragonfly. We used Ladybug and Honeybee plugins to get UTCI values. Ladybug and Dragonfly plugins helped us to get energy consumption values. Ladybug is common factor that we link it to the EPW file to get temperature of Aswan. The EPW file for Aswan Weather was exported from the NASA website. The climate zone was selected: as very hot; the construction type was selected: mass and the system type for cooling air inside buildings at the level of URD was selected: PTHP.

Fig. 10
figure 10

Wind tunnel and its dimensions for simulation in Autodesk CFD

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5 Result and discussion

In this research, the results were divided into four stages using two simulation programs to reach an appropriate URD form in New Aswan. The results of each stage were as follows:

5.1 The pressure difference between buildings in URD

The first stage in the results is to simulate the pressure difference between buildings for each of the four scenarios at a height of 10 m using Autodesk CFD. The results were different in the wind tunnel for each scenario, as shown in (Fig. 11).

Fig. 11
figure 11

(a) The pressure difference between buildings in scenario A, (b) The pressure difference between buildings in scenario B, (c) The pressure difference between buildings in scenario C

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There is a pressure difference in scenarios C and non-existent in scenarios A and B. The results in (Fig. 11) showed that the arrangement of the buildings and their orientation in the URD affect the formation of the pressure difference between the buildings. The pressure difference between buildings is important because it affects NV and air movement. Therefore, the new arrangement of buildings and reorientation East-West in scenario C achieves a pressure difference between buildings in URD, which improves air movement and NV.

5.2 Wind movement in wind corridors between buildings in URD

The second stage in the results is the simulation of wind movement between buildings for each of the four scenarios at a height of 10 m using CFD Autodesk. The results were different in the wind tunnel for each scenario. The wind movement differed in each scenario, as shown in (Figs. 12, 13, 14).

Fig. 12
figure 12

The wind movement in scenario A: (a) The wind movement at a height of 10 m, (b) The wind movement at section (A-1), (c) The wind movement at section (A-2)

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Fig. 13
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The wind movement in scenario B: (a) The wind movement at a height of 10 m, (b) The wind movement at section (B-1), (c) The wind movement at section (B-2)

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Fig. 14
figure 14

The wind movement in scenario C: (a) The wind movement at a height of 10 m, (b) The wind movement at section (C-1), (c) The wind movement at section (C-2)

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The results in (Figs. 12, 13 and 14) showed that wind movement in the wind corridors was weak in scenarios A and B but improved slightly in scenario C. Thus, it was confirmed that the pressure difference in scenario C achieved good wind movement in the wind corridors between buildings, which improved NV between buildings.

5.3 Outdoor thermal comfort between buildings in URD (UTCI values)

The third stage in the results is the simulation of outdoor thermal comfort between buildings for each of the three scenarios using Rhino7, Grasshopper, and Ladybug software. Certain months were chosen, namely the six summer months from April to September 2021, the hottest months of the year, and temperatures exceeding 40 °C on most days.

This stage focuses more on specific days and hours to obtain more accurate simulation results in each of the six summer months. The highest recorded temperature on a specific day at a specific hour in each month was taken for each scenario according to (Fig. 3). The outdoor thermal comfort (UTCI values) differed in each scenario, as shown in (Fig. 15).

Fig. 15
figure 15

UTCI values of outdoor thermal comfort by focusing on specific days and hours for accurate results in each of the six summer months for scenario A, B and C

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The results in (Fig. 15) showed that the UTCI values were more accurate by day and hour, as temperature recording was high in scenario A and then began to improve slightly in scenario B. However, the greatest improvement was in scenario C.

When scenario A compared to scenarios B and C, it was found that UTCI values in scenarios B and C decreased by 4 °C and 4.2 °C, respectively, at specific hours over the six different days in the six summer months in 2021. It was observed that scenario C recorded the lowest UTCI values.

However, the differences in the UTCI values ​​between scenarios A and C are few, but in a hot arid like Aswan, reducing the UTCI values ​​even by a slight percentage makes a difference. A report from the BBC indicated that global warming would cause catastrophic changes worldwide, such as holes in the ozone layer, energy crises, drought, and other disasters. There is currently a vicious cycle in the urban environment that energy consumption is causing an increase in the average global temperature over the coming decades. Whereas every 5–10 years, the average global temperature rises by about 0.06 °C, and every ten years, the average global temperature has increased by 0.16 °C in the past thirty years. The global average temperature at the end of the twenty-first century will increase by 1.5–4.4 °C (Yu et al., 2022).

5.4 Energy consumption inside buildings in URD

The fourth stage in the results is the simulation of energy consumption at level of twelve buildings inside URD for each scenario using Rhino7, Grasshopper, and Dragonfly software. An energy consumption simulation was made for the six summer months in 2021, from April to September. The energy consumption results in the residential urban area differed in each scenario, as shown in (Fig. 16).

Fig. 16
figure 16

Energy consumption for the six summer months in the year 2021 at level of twelve buildings inside URD of scenario A, B and C

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The results in (Fig. 16) showed that the highest energy consumption at level of twelve buildings inside URD was recorded in scenario A and energy consumption began to decrease in scenario B. However, scenario C recorded the lowest rate of energy consumption. Here, the effect of achieving the pressure difference, good air movement, NV, and reducing the UTCI values ​​in scenario C appeared to reduce energy consumption significantly. When scenario A compared to scenarios B and C, it was found that energy consumption in scenarios B and C decreased by 116.17768 kWh and 10407.28946 kWh, respectively. It was observed that scenario C recorded the lowest rate of energy consumption. Minimizing energy usage plays a crucial role in attaining sustainability objectives and lessening environmental effects (Wang et al., 2023; Zhuang et al., 2022).

As mentioned in the literature review’s introduction, focusing on the planning of URDs, specifically the arrangement of buildings, creates pressure differences between them, ensuring good natural ventilation. This results in outdoor and indoor thermal comfort, subsequently reducing energy consumption and achieving sustainable and environmentally friendly planning. Additionally, as highlighted in the studies of the literature review in biomimicry and sustainable built environment, sustainable and eco-friendly planning can be realized through the application of biomimicry. The results indicate that rearranging buildings in case study of scenarios B and C for URD planning using biomimicry achieved pressure differences between the buildings as shown in (Fig. 11 (b, c)), leading to improved wind movement as shown in (Figs. 13 and 14). Then a reduction in UTCI values of scenarios B and C by 4 °C and 4.2 °C, respectively, at specific hours over six different days in the six summer months as shown in (Fig. 15). This, in turn, resulted in decreased energy consumption at the level of twelve buildings inside URD as shown in (Fig. 16). Therefore, satisfactory results were obtained for achieving sustainability in the planning and arrangement of buildings in URDs areas, whether in Egypt or any hot-arid worldwide in the future.

6 Conclusion

Aswan is one of the Egyptian cities that suffer from a severe rise in temperatures throughout the summer, reaching more than 40 °C. Therefore, attention must be paid to building sustainable URDs in New Aswan.

There are many solutions to build sustainable URDs with good NV between buildings to improve outdoor thermal comfort by reducing UTCI values and energy consumption inside buildings at level of URDs. In this research, one solution was chosen: rearranging and reorienting the buildings in a different and innovative manner using biomimicry. So, the solution and the idea were taken from the prairie dog’s burrow to achieve a pressure difference between buildings, which resulted in good NV between buildings and lower UTCI values which help to improve outdoor thermal comfort, thus reducing energy consumption inside buildings at level of URDs.

Scenario A represents a traditional arrangement and orientation of buildings used in most URDs; it did not achieve pressure difference, good ventilation, low UTCI values, or energy savings. Scenarios B and C are the new innovative scenarios for rearranging and reorienting buildings in URD based on prairie-dog’s burrow. Scenario B did not achieve the strong results of achieving the pressure difference and natural ventilation between the buildings, thus achieving indoor and outdoor thermal comfort, which results in reducing energy consumption in the URD compared to scenario A. Nevertheless, the arrangement and orientation (East-west) of the buildings in the URD in scenario C gave distinct results compared to scenario A, as the pressure difference was achieved between the buildings, which helped in good natural ventilation. Therefore, the UTCI values ​​decreased, which resulted in reducing energy consumption in the URD. In scenario C, the UTCI values and energy consumption are lower than in scenario A, at a rate of 4.2 °C at specific hours over the six different days in the six summer months and 10407.28946 kWh, respectively.

The results differences between scenarios A, B, and C are simple but cannot be ignored. The difficulty of the temperature inside the city of Aswan, reducing even one degree Celsius per day, causes a difference in energy consumption inside buildings and in outdoor thermal comfort. Scenario C consists of 12 residential buildings. When applying the idea to more than one URD, each of them contains 12 buildings in New Aswan; this makes a big difference for the city as a whole in reducing UTCI values at a rate of 4.2 °C at specific hours over the six different days in the six summer months for each 12 buildings to achieve indoor and outdoor thermal comfort and then save energy. Thus, new sustainable Egyptian cities are obtained.

It is possible to build sustainable URDs in hot-arid and solve the problems of outdoor thermal comfort, outdoor natural ventilation, and energy conservation inside buildings by searching for solutions in nature through biomimicry.

As we mentioned earlier, there is an extension to New Aswan city covering approximately 18,490.92 acres. In this new expansion, we will try to implement a case study (Scenario C) for the URDs to create a pressure difference between buildings, enhance natural ventilation, and consequently reduce UTCI values. This, in turn, leads to a reduction in energy consumption and future cost savings within the new extension of New Aswan city. This study allows us to achieve sustainability and environmentally friendly planning of URDs, emphasizing a commitment to sustainable future for New Aswan city or any other new cities worldwide. The importance of our case study lies in its applicability across new cities worldwide not only in Egypt, offering strategies tailored to address climatic challenges in hot-arid during planning sustainable URDs.

6.1 Recommendations

We recommend all responsible authorities involved in planning new cities to adopt the biomimicry approach outlined in our study to achieve sustainable and environmentally friendly URDs.

6.2 Limitations

It is not possible to determine whether our study is suitable for planning in areas experiencing extreme cold, as our study aims to reduce UTCI values and consequently decrease cooling energy consumption specially in hot-arid. However, in extremely cold regions, the goal is to raise temperatures to reduce heating energy consumption.

When constructing multiple buildings in the form of an attached block, it hinders what we aim for in our study, which is leaving a specified space between each building and the other to allow for natural ventilation and pressure difference.

In the case of constructing each building separately, this poses a challenge and does not fulfill the purpose of the study because, in this scenario, planning is done at the level of each individual building. Therefore, the benefit of this study lies in planning on a larger scale for multiple buildings at the same time.

7 Future work

It is possible to look again at building sustainable URDs by reconsidering the shape of the buildings with the introduction of water and green elements in the design.